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Cover of Bioterrorism Threats to Our Future: The Role of the Clinical Microbiology Laboratory in Detection, Identification, and Confirmation of Biological Agents

Bioterrorism Threats to Our Future: The Role of the Clinical Microbiology Laboratory in Detection, Identification, and Confirmation of Biological Agents

This report is based on a colloquium sponsored by the American Academy of Microbiology and the American College of Microbiology held October 27-29, 2000, in San Antonio, Texas.
Washington (DC): American Society for Microbiology; .

A colloquium was convened by the American Academy of Microbiology and the American College of Microbiology to discuss the role of the clinical microbiology laboratory in the detection, identification, and confirmation of biological agents that could be used in a bioterrorism event. The colloquium was held in San Antonio, Texas, October 27-29, 2000. The principal findings of the colloquium are summarized below.

Professional microbiologists, in conjunction with clinicians, will play a central role in the detection of agents associated with bioterrorism. In collaboration with state and federal agencies, they will help to determine when a bioterrorism event has occurred. In the case of a possible bioterrorism event, the key responsibilities of the hospital-based clinical microbiology laboratory are to be familiar with the likely agents of bioterrorism and to be prepared to use the Level A laboratory algorithms designed for the detection of these agents. Using these algorithms, clinical microbiology laboratories rule out bioterrorism-related microorganisms and identify suspicious isolates. However, at the present time, there is an acute shortage of trained clinical microbiologists who will be required for clinical microbiology laboratories to carry out these responsibilities. In particular, relaxation of the educational standards for laboratory workers by the Clinical Laboratory Improvements Amendments of 1988 (CLIA ’88) legislation has potentially increased the likelihood of bioterrorism pathogens being overlooked.

Several other factors may hamper recognition of a possible bioterrorism threat. Terrorists are likely to select the most vulnerable locations: perhaps small cities or rural areas where microbiology expertise may be difficult to find. Widely used, commercially available identification systems utilized by clinical microbiology laboratories in routine daily operations do a poor job of identifying uncommon and slow-growing microorganisms that are expected to be associated with bioterrorism events, such as Brucella and Francisella. Moreover, the cause of a bioterrorism event may be an agent not on the list of likely pathogens. A bioterrorism attack with an emerging agent, such as West Nile virus or Hantavirus, might be difficult to deliver, but would be most difficult to detect.

An event is most likely to be signaled by many people getting sick around the same time and with similar symptoms. Event recognition is thus a team effort; effective channels of communication must be in place between clinicians, particularly infectious disease physicians and emergency room personnel, and the microbiology laboratory. Since recognition depends on clusters of infections, the small number of cases seen by a laboratory or infectious disease physician at a single institution might not arouse suspicion. Recognition may require sharing knowledge of cases occurring at several institutions within a region. However, at the present time, the infrastructure for interinstitutional communication of possible bioterrorism cases needs augmenting.

Most clinical microbiology laboratories have access to the Laboratory Response Network (LRN), a system created to provide an organized response for the detection and diagnosis of biological agents. The LRN is the essential organizational unit for detection of and response to a possible covert bioterrorism threat. At the advanced level, where specimens suspected of containing a possible bioterrorism agent would be subjected to detailed analysis, effective components of the LRN have been put in place. But additional training and communication need to be established in clinical microbiology laboratories that will act as sentinels to detect a possible bioterrorism threat.

When a bioterrorism event occurs or is even suspected, several consequences will impact the laboratory's ability to function effectively. A flood of specimens may overwhelm the laboratory's capacity and exhaust available testing reagents. Fearful workers may be reluctant to handle specimens that could contain dangerous pathogens; some technologists may not come to work. Many specimens or isolates may need to be shipped to a higher-level laboratory for further testing, which requires special packaging. In addition, the laboratory may be subject to numerous inquiries about test results from patients, families, and the news media. For a laboratory to manage these disruptions it must have a bioterrorism response plan and laboratory workers must be trained in and familiar with the plan.

Several new rapid technologies are available in the clinical micro-biology arena. Exploitation of these technologies to devise improved assays for identifying possible agents of bioterrorism would enhance the ability of both sentinel and advanced micro-biology laboratories to detect a possible bioterrorism threat.

The success of the public health response to the bioterrorism threat depends on a national effort that must involve all levels of the health care system, from local to federal. Benchmarks must include public education, medical laboratory and practitioner training, standardization of emergency preparedness plans, and defined lines of communication both within the health care system and extending to law enforcement agencies.

Front Matter

We gratefully acknowledge the following organizations for their support of the colloquium:

American Society for Microbiology

Becton Dickinson Biosciences

BioMérieux, Inc.

SmithKline Beecham Pharmaceuticals

Transgenomic, Inc.

American Academy of Microbiology Board of Governors

Eugene W. Nester, Ph.D. (Chair) University of Washington

Joseph M. Campos, Ph.D. Children's National Medical Center Washington, DC

R. John Collier, Ph.D. Harvard Medical School

Marie B. Coyle, Ph.D. University of Washington

James E. Dahlberg, Ph.D. University of Wisconsin, Madison

Julian E. Davies, Ph.D. TerraGen Diversity, Inc. University of British Columbia

Arnold L. Demain, Ph.D. Massachusetts Institute of Technology

Mary Jane Osborn, Ph.D. University of Connecticut Health Center

Lucia B. Rothman-Denes, Ph.D. University of Chicago

Anna Marie Skalka, Ph.D. Fox Chase Cancer Center Philadelphia, PA

Abraham L. Sonenshein, Ph.D. Tufts University Medical School

American College of Microbiology Board

Joseph M. Campos, Ph.D. (Dean) Children's National Medical Center Washington, DC

Craig W. Day Nelson Laboratories, Inc. Salt Lake City, UT

Richard L. Hodinka, Ph.D. Children's Hospital of Philadelphia

James D. MacLowry, M.D. Oregon Health Sciences University

Noel R. Rose, M.D., Ph.D. Johns Hopkins University School of Hygiene and Public Health

Michael Saubolle, Ph.D. Good Samaritan Medical Center Phoenix, AZ

Susan E. Sharp, Ph.D. Mount Sinai Medical Center Miami Beach, FL

Richard B. Thomson, Jr., Ph.D. Evanston Northwestern Healthcare

Daniel P. Weingarten, Ph.D., J.D. Department of Transportation State of California

Colloquium Steering Committee

James W. Snyder, Ph.D. (Chair) University of Louisville School of Medicine

Joseph M. Campos, Ph.D. Children's National Medical Center Washington, DC

Mary J. Gilchrist, Ph.D. University of Iowa

Peter H. Gilligan, Ph.D. University of North Carolina Hospitals

J. Michael Miller, Ph.D. Centers for Disease Control and Prevention

Susan E. Sharp, Ph.D. Mount Sinai Medical Center Miami Beach, FL

Colloquium Participants

Ronald M. Atlas, Ph.D. University of Louisville

Matthew J. Bankowski, Ph.D. ViroMed Laboratories, Inc. Minneapolis, MN

Michael Bell, M.D. Centers for Disease Control and Prevention

Barbara A. Body, Ph.D. Laboratory Corp. of America Burlington, NC

Joseph M. Campos, Ph.D. Children's National Medical Center Washington, DC

David W. Craft, Ph.D. Walter Reed Army Medical Center Washington, DC

Judy A. Daly, Ph.D. University of Utah

Jed Doyle Transgenomic Inc. Omaha, NE

Mary J. Gilchrist, Ph.D. University of Iowa

Peter H. Gilligan, Ph.D. University of North Carolina Hospitals

Lizzie J. Harrell, Ph.D. Duke University Medical Center

Erik A. Henchal, Ph.D. USAMRIID Frederick, MD

Raymond L. Kaplan, Ph.D. Quest Diagnostics Tucker, GA

Gary K. Keck Bloomington Health Bloomington, IN

Michael Kimberly, Ph.D. Tennessee Central Laboratory Nashville, TN

Dyan Luper Christus Spohn Health System Corpus Christi, TX

Richard Meyer, Ph.D. Centers for Disease Control and Prevention

J. Michael Miller, Ph.D. Centers for Disease Control and Prevention

Stephen A. Morse, Ph.D. Centers for Disease Control and Prevention

David M. Robinson, Ph.D. Battelle Memorial Institute Columbus, OH

Susan E. Sharp, Ph.D. Mount Sinai Medical Center Miami Beach, FL

Craig E. Smith, M.D. Phoebe Putney Memorial Hospital Albany, GA

James W. Snyder, Ph.D. University of Louisville School of Medicine

Lynn Steele-Moore Christiana Care Health System Wilmington, DE

Alice Weissfeld, Ph.D. Microbiology Specialists, Inc. Houston, TX

David F. Welch, Ph.D. Laboratory Corp. of America Dallas, TX

Mary K. York, Ph.D. University of California, San Francisco iv

Executive summary

A colloquium was convened by the American Academy of Microbiology and the American College of Microbiology to discuss the role of the clinical microbiology laboratory in the detection, identification, and confirmation of biological agents that could be used in a bioterrorism event. The colloquium was held in San Antonio, Texas, October 27-29, 2000. The principal findings of the colloquium are summarized below.

Professional microbiologists, in conjunction with clinicians, will play a central role in the detection of agents associated with bioterrorism. In collaboration with state and federal agencies, they will help to determine when a bioterrorism event has occurred. In the case of a possible bioterrorism event, the key responsibilities of the hospital-based clinical microbiology laboratory are to be familiar with the likely agents of bioterrorism and to be prepared to use the Level A laboratory algorithms designed for the detection of these agents. Using these algorithms, clinical microbiology laboratories rule out bioterrorism-related microorganisms and identify suspicious isolates. However, at the present time, there is an acute shortage of trained clinical microbiologists who will be required for clinical microbiology laboratories to carry out these responsibilities. In particular, relaxation of the educational standards for laboratory workers by the Clinical Laboratory Improvements Amendments of 1988 (CLIA ’88) legislation has potentially increased the likelihood of bioterrorism pathogens being overlooked.

Several other factors may hamper recognition of a possible bioterrorism threat. Terrorists are likely to select the most vulnerable locations: perhaps small cities or rural areas where microbiology expertise may be difficult to find. Widely used, commercially available identification systems utilized by clinical microbiology laboratories in routine daily operations do a poor job of identifying uncommon and slow-growing microorganisms that are expected to be associated with bioterrorism events, such as Brucella and Francisella. Moreover, the cause of a bioterrorism event may be an agent not on the list of likely pathogens. A bioterrorism attack with an emerging agent, such as West Nile virus or Hantavirus, might be difficult to deliver, but would be most difficult to detect.

An event is most likely to be signaled by many people getting sick around the same time and with similar symptoms. Event recognition is thus a team effort; effective channels of communication must be in place between clinicians, particularly infectious disease physicians and emergency room personnel, and the microbiology laboratory. Since recognition depends on clusters of infections, the small number of cases seen by a laboratory or infectious disease physician at a single institution might not arouse suspicion. Recognition may require sharing knowledge of cases occurring at several institutions within a region. However, at the present time, the infrastructure for interinstitutional communication of possible bioterrorism cases needs augmenting.

Most clinical microbiology laboratories have access to the Laboratory Response Network (LRN), a system created to provide an organized response for the detection and diagnosis of biological agents. The LRN is the essential organizational unit for detection of and response to a possible covert bioterrorism threat. At the advanced level, where specimens suspected of containing a possible bioterrorism agent would be subjected to detailed analysis, effective components of the LRN have been put in place. But additional training and communication need to be established in clinical microbiology laboratories that will act as sentinels to detect a possible bioterrorism threat.

When a bioterrorism event occurs or is even suspected, several consequences will impact the laboratory's ability to function effectively. A flood of specimens may overwhelm the laboratory's capacity and exhaust available testing reagents. Fearful workers may be reluctant to handle specimens that could contain dangerous pathogens; some technologists may not come to work. Many specimens or isolates may need to be shipped to a higher-level laboratory for further testing, which requires special packaging. In addition, the laboratory may be subject to numerous inquiries about test results from patients, families, and the news media. For a laboratory to manage these disruptions it must have a bioterrorism response plan and laboratory workers must be trained in and familiar with the plan.

Several new rapid technologies are available in the clinical micro-biology arena. Exploitation of these technologies to devise improved assays for identifying possible agents of bioterrorism would enhance the ability of both sentinel and advanced micro-biology laboratories to detect a possible bioterrorism threat.

The success of the public health response to the bioterrorism threat depends on a national effort that must involve all levels of the health care system, from local to federal. Benchmarks must include public education, medical laboratory and practitioner training, standardization of emergency preparedness plans, and defined lines of communication both within the health care system and extending to law enforcement agencies.

Scenario

On a mid-November day, primary care doctors in Boston begin seeing patients with flu-like symptoms—high fever, rapid heartbeat, and headache. “Looks like flu season is starting,” they say to themselves. They counsel patients to rest and take plenty of fluids, then send them home. Some of the patients seem sicker than one would expect with flu, but the doctors just conclude that it will be a more severe flu season this year.

However, one of the physicians, Dr. Susan Pedersen, isn't satisfied with this explanation. She notices that some patients whom she first sees with the usual symptoms return more severely ill in a day or two; they have bothersome chest pain, shortness of breath, and persistent cough. Moreover, some of the patients are in their 30s and 40s, too young to be so sick from simple flu. Dr. Pedersen takes respiratory samples from some of her sicker patients and sends them to the hospital microbiology laboratory with a request to confirm influenza virus.

On her way out of the office that night, she tells one of her colleagues what she has done. “The lab is not going to be reimbursed for those tests,” he warns her. “Your patient is going to end up footing the bill.” “We'll see,” she replies. “I picked patients who have good coverage. Anyway, I want to know what's going on. Some of these patients told me they had gotten flu vaccine. Maybe they guessed wrong on the vaccine strain.” Her colleague is skeptical. But the next day, he too sends a few selected specimens for microbiological analysis.

In the laboratory, a few samples stain positive for influenza virus, but many do not. That afternoon, one of the technologists tells the laboratory director, Dr. Mary Lou Henderson, about these results, knowing that she likes to hear about anything unusual. Dr. Henderson is not worried, since she knows that many specimens from patients with respiratory infections test negative for flu virus. Other viruses can cause respiratory infections. And anyway, the test for influenza virus isn't one hundred percent sensitive.

But when the same pattern is repeated over the next few days, Dr. Henderson begins to wonder whether the obvious explanation is the correct one. She notices that Dr. Pedersen has sent several samples and calls her. During that conversation, she learns of the increasing severity of the illness in many patients. Unused portions of the specimens have been saved, and Dr. Henderson has a technologist plate samples onto several kinds of growth medium, including blood agar. At lunch that day she sees one of the hospital's infectious disease specialists, Dr. Robert Koch, and tells him what is happening. He in turn gives her a startling bit of news: “I have been called to consult on several patients in the last day or two who have been admitted to the hospital in respiratory distress with bloody sputum.” She promises to tell him what she finds from the cultures.

The next day they look at the plates and the Gram stains together. Small colonies have grown on the plates, especially the blood agar plate. On Gram stains, the organisms show up as gram-negative rods, which would usually suggest intestinal bacteria, such as Salmonella or Shigella. But these patients don't have diarrhea; they have severe respiratory illness, with nausea, vomiting, chest pain, cough, mental confusion, and shortness of breath. Some are even comatose. At this point, Dr. Henderson remembers something from a course on bioterrorism that she took a few years ago. “Could this be Yersinia pestis?” she asks, half-afraid that she is being an alarmist for mentioning the organism that causes plague. Dr. Koch looks at her. “Why would plague be here in Boston?” he asks. “That only occurs in the Western states.”

Nonetheless, he agrees that all the results so far—both in the patients and in the laboratory—fit the profile of this pathogen. And he has no better ideas. So Dr. Henderson sets up a few simple biochemical screening tests from a proposed protocol to rule out Y. pestis. Results available the next day are consistent with this bacterium.

At this point, facing the unthinkable, the two professionals decide to gather additional facts. They call their respective colleagues at adjoining hospitals. Several hospitals are admitting patients with severe respiratory illness, Dr. Koch learns. And Dr. Henderson finds one other microbiology laboratory director who has gone down the same investigative path that she has pursued and found the same results.

Faced with this further evidence, they divide up the tasks at hand. Dr. Henderson calls the hospital infection control physician and tells him that a few technologists who have worked with the enigmatic specimens may have been exposed to the plague bacillus. She arranges a time when they can both meet with the technologists and inform them, as well as suggesting possible steps to reduce their chance of becoming ill. She also invokes the bioterrorism preparedness plan that they had worked up a few years before and hopes that the technologists remember their training. She has one technologist put the specimens and cultures into a biological safety cabinet and has another package up several specimens in special shipping containers to send to the state public health laboratory, which has facilities for further analyzing the specimens. She then calls the director of that laboratory and relays all of the pertinent information, including the fact that the specimens are on their way.

Finally, she calls a hospital administrator and lets him know that there may be a plague outbreak in process. He is incredulous and afraid of giving the hospital a bad name if they warn of a plague outbreak, causing mass hysteria, and turn out to be wrong. Eventually he calms down when he realizes that the epidemic is already affecting several hospitals and that any notice of a threat to the public health will come not from his individual hospital, but from a state public health officer.

In the meantime, Dr. Koch and his infectious disease colleagues call the many primary care doctors who sent patients with the mysterious respiratory illness to the hospital or who sent specimens to the laboratory and tells them what they suspect. He recommends treating patients with streptomycin, gentamicin, doxycycline, or chloramphenicol. Then he reports all of this information to the state epidemiologist, who conducts a quick telephone investigation. Soon he calls back and confirms that an outbreak of a severe and possibly lethal respiratory ailment is widespread in the Boston area, as well as in some of the less populated areas of the state.

An alternative course is taking place in a smaller hospital a short distance away. That hospital's microbiology laboratory has also received specimens from patients with the flu-like respiratory illness. At that hospital, however, due to budget cuts, there is no trained microbiology supervisor. So when the specimens stain negative for influenza virus, a medical technologist puts some samples into a commercial identification system, which reports the next day that the specimens contain Shigella. Since there is no expert microbiologist to review the results, no one questions why an intestinal bacterium would be causing a respiratory illness.

Because Shigella is a reportable disease, the technologist notifies the county health department and sends them the isolates for species identification. It happens that the isolates are sent on a Friday, and the county laboratory does not work on weekends. So it is about a week before that laboratory realizes that the strains are not Shigella and sends them on to the state laboratory, which has already confirmed an outbreak of Y. pestis.

Introduction

Biological warfare has been known since the Middle Ages. In the 14th century, the Tatars catapulted the bodies of bubonic plague victims into the walled city of Kaffa, an economically important port that they were besieging. It was infected residents fleeing this siege who spread the Black Death throughout Western Europe. The Spanish conquistadors and the British used smallpox, measles, and perhaps other agents to help subdue Native American peoples by providing them with blankets and handkerchiefs contaminated with these organisms. Since the Native Americans had never before been exposed to these pathogens, they had virtually no natural immunity to them.

Bioterrorism does not need to be directed against human life to be effective, but can also be directed against water and food sources. The ancient Romans, among others, threw carrion into wells to poison their adversaries' drinking water. A bioterrorism event could also target the agricultural sector, through either animals or crops.

The reality of modern-day biological terrorism was brought to the forefront in 1997, when the Federal Bureau of Investigation (FBI) arrested a man in Las Vegas, Nevada, who was found to be carrying the agent of anthrax. Although this individual was in possession of the avirulent vaccine strain of the anthrax organism, this incident served as a reminder of how easily a terrorist act could potentially cause serious illness and panic in the civilian population.

Huge expenditures have been made throughout the world both to produce biological weapons and to develop the means to protect military populations from these agents. Much less consideration, however, has been given to what steps need to be taken to protect civilian populations. One example of how an attack on a civilian population might unfold was the contamination of salad bars with Salmonella typhimurium in The Dalles, Oregon, in 1984 by followers of the cult leader Baghwan Sri Rajneesh. In that case, followers of Sri Rajneesh attempted to incapacitate the population of The Dalles on election day in order to influence the outcome of a local election. Even though the organism that they used is generally regarded as a microbial pathogen of low virulence, more than 750 people fell ill from food poisoning. Fortunately, none died. This incident demonstrated the relative ease with which microorganisms can be obtained and disseminated: the bacterial cultures used were grown in a clinical laboratory at the cult's compound in Oregon. Perhaps most striking, the intentional nature of this incident was not detected at the time it occurred. It only came to light a year later, when a former cult member revealed it during the course of a separate criminal investigation.

A less successful, but more frightening, example of attempted civilian bioterrorism occurred in Japan in the early 1990s. The Aum Shinrikyo cult is known for releasing sarin nerve gas inside the Tokyo subway system. What is not generally known is that they had previously attempted on several occasions to disseminate botulinum toxin and the anthrax agent among the general population. No illnesses are known to have resulted from these incidents, probably, at least in part, because insufficiently virulent strains were used. However, with further trials, Aum Shinrikyo might well have succeeded in their macabre campaign.

Clearly bioterrorism appeals not only to nations, both large and small, but particularly to terrorist groups. Some have suggested that biological agents are more likely to be used by terrorist groups than by belligerent nations. One major reason is that the capacity to produce and effectively spread biological weapons requires relatively little in the way of sophisticated technology. For this reason, biological weapons have been called “the poor man's atom bomb.” Indeed, recipes for producing biological weapons are available on the Internet. Most colleges, universities, and hospitals in the United States—and even some high schools—have facilities that could be used to produce crude versions of biological weapons that might be used to terrorize individuals, community organizations, churches, schools, and cities. In addition, the apparent ease with which these weapons may be produced has resulted in hundreds of threats, particularly letters claiming that the person who opened them has been exposed to anthrax spores. So far these incidents have been found to be hoaxes. Yet at the time they occur, they generate considerable anxiety and must be dealt with seriously.

While biological weapons may not immediately produce the massive casualties and destruction wreaked by chemical and radiological weapons, they pose their own insidious danger. Unlike chemical and radiological weapons, individuals affected by agents of microbial terrorism only slowly develop signs and symptoms of disease after exposure—a lag time that is known as the incubation period—and so could escape diagnosis for many days. Also, since infectious diseases often begin with mild symptoms and only manifest their true character with time, an illness caused by a bioterrorism agent may initially be incorrectly interpreted as a less severe natural infection, further delaying recognition of the event. Finally, recognition of a bioterrorism attack will require an appreciation of a cluster of infections—possibly with unusual organisms. Since infected individuals would either report to an emergency room (ER) or see their personal care physicians one at a time, and since they would most likely be scattered across many ERs and the practices of many different physicians, it could take days to weeks for the telltale pattern to become epidemiologically evident.

These delays would be damaging. By the time public health officials realized that a deadly strain had been released upon our population, medical facilities would already be overwhelmed. Many emergency personnel—firefighters, paramedics, police officers, and hospital emergency room workers—would have unknowingly been exposed, incapacitating the very professionals who would be needed to combat the outbreak. Moreover, infected persons who continued to move about in the population during the early, mild stage of their illness could be spreading the disease to others.

Although most experts agree that the probability of a bioterrorist attack is low, they also believe that it is no longer a matter of “whether” but “when” such an attack will occur. Allocation by the Federal government of $1.4 billion during fiscal year 2000 to fight biological and chemical terrorism is strong testimony to the credibility now given to the possibility of a bioterrorism incident. Much of this increased credibility has arisen from revelations about the scope of the biological weapons program conducted in the former Soviet Union by the Soviet defector Ken Alibeck, who was Deputy Director of this program, called Biopreparat. Although the program no longer officially exists, biological materials prepared under Biopreparat are not all accounted for, and some experts fear that scientists formerly employed in Biopreparat may be tempted to sell their expertise to terrorist groups or small nations seeking to develop a biological weapons capability.

Because the threat of a bioterrorist attack is now perceived as real, the diagnostic microbiology laboratory must be prepared to collaborate closely with clinicians to detect rapidly and efficiently potential biological agents that could be used in such an incident. The clinical microbiology laboratory will have a very significant role in the determination of whether or not a bioterrorism event has taken place and, if an attack is occurring, what kind of agent is being used. In the event of a biological attack, the early recognition and detection of the causative agent will pose a formidable challenge to the microbiologist and the clinical microbiology laboratory staff. Not only will the clinical microbiology laboratory be expected to detect and identify the agent in a timely manner, but it also will be expected to provide information regarding the selection, collection, safe handling, and transport of specimens to an appropriate laboratory with a level of biosafety capability compatible with the potential threat.

Rapid and accurate identification of the biological agent will be critical to implementation of control measures to treat those already infected and to contain the spread to additional individuals. Without the expertise of clinical microbiology laboratories that are trained to detect and identify a biological agent rapidly and accurately, the health care delivery system may be unable to provide appropriate medical care and to institute necessary preventive measures in a timely manner. Thus, the clinical microbiology laboratory is a sentinel that will play a vital and pivotal role in the event of a terrorist action involving biological agents.

Whether an outbreak of infectious disease is due to a terrorist incident, such as contamination of a salad bar with Salmonella, or a naturally occurring infection, such as Cryptosporidium contamination of a community water supply, the rapid response of the microbiology laboratory will be equally important in protecting public health. Clinical microbiology laboratories are staffed with professionals who are well-trained and who practice on a daily basis the skills and techniques necessary to detect, recover, and identify any agent causing infectious disease. Enhancing these capabilities of the clinical microbiology laboratory with regard to bioterrorism will have the added benefit of enhancing the laboratory's capabilities in routine daily health care. More-sensitive detection methods for biowarfare agents may enter the microbiology laboratory as rapid, improved diagnostics for naturally acquired infectious diseases from both conventional and newly emerging organisms. And more-effective networks to coordinate the emergency response to a bioterrorism event will translate into better mechanisms for dealing with natural outbreaks of both conventional and emerging infectious diseases.

Ensuring that all levels of our medical and public health communities are ready to detect and combat a bioterrorism attack will allow the public to have confidence that we are prepared to meet this challenge and to assist in their protection. This readiness must start with the sentinels of the diagnostic microbiology laboratory and the professionals who staff it. At the colloquium, experienced microbiologists addressed the relevant issues and delineated the necessary guidelines for the clinical microbiology laboratory to ensure our readiness for a potential attack. Their analysis and recommendations are set out in this document.

Bioterrorism events and the role of the clinical laboratory

Recognizing a bioterrorism event

The manner in which a bioterrorism event is recognized will depend on whether it is overt or covert. Overt events are self-evident in that they are obvious or are announced when they happen. One type of overt event that has actually occurred a number of times is the opening of an envelope containing a note announcing that it is filled with Bacillus anthracis spores. Fortunately, the large majority of these events have been hoaxes. Covert events are hidden and not recognized until victims seek health care.

In the case of a covert event, a suspicion of bioterrorism may be raised initially because of unusual microbiology laboratory test results. A laboratory staffed by a board-certified microbiology specialist (i.e., American Board of Medical Microbiology [ABMM]) either as a director or consultant is better able to detect the type of unusual microbiology laboratory test result—or pattern of test results—that can raise suspicion that a bioterrorism event may be occurring. A laboratory with a certified microbiologist at the director level is also better positioned to see possibly important patterns during review of laboratory results, is capable of interpreting these patterns, and can extrapolate similar results from different patients as suggesting a bioterrorism event. Technologists, on the other hand, may be familiar only with cultures they have worked on and may overlook the significance of a single unusual result.

At the present time, the ability of clinical microbiology laboratories to detect bioterrorism events may be hampered for the following reasons:

  • Relaxation of the educational standards for laboratory workers by the CLIA ‘88 legislation has increased the likelihood of bioterrorism pathogens being overlooked, possibly leading to misdiagnosis and inappropriate therapy, the potential for increased risk of laboratory accidents, or further spread of the disease.
  • Terrorists are likely to select the most vulnerable locations, perhaps small cities or rural areas where microbiology expertise may be difficult to find.
  • One impact of managed care has been to discourage laboratory testing of patients with flu-like illnesses who are not ill enough to require hospitalization. Not obtaining microbiology laboratory results for patients with flu-like illnesses may delay recognition of bioterrorism attacks with pathogens that initially present with respiratory symptoms, such as Yersinia pestis, the agent of pneumonic plague, or Bacillus anthracis, the agent of anthrax.
  • The cause of a bioterrorism event may be an agent not on the list of likely pathogens, which is focused on biological agents that require comprehensive public health planning (reagents, drugs, vaccines, etc.). In addition, a bioterrorism attack with an emerging agent, such as West Nile virus or Hantavirus, would be most difficult to detect.
  • An event is most likely to be signaled by many people getting sick. Since recognition depends on clusters of infections, the small number of cases seen by a laboratory or infectious disease physician at a single institution might not arouse suspicion. Recognition may require sharing knowledge of cases occurring at several institutions within a region. However, the infrastructure for interinstitutional communication of possible bioterrorism cases needs augmentation. So, in the present situation, an event may only be recognized at a higher level, such as a state public health laboratory, into which suspicious specimens from several local laboratories (possibly including veterinary laboratories) have been funneled. Recognition at this higher level would take longer, allowing the organism to spread unchecked.
  • Finally, there are insufficient numbers of clinical microbiologists familiar with bioterrorism in general. The American College of Microbiology may wish to expand its activities to accredit training programs that include modules that deal with the role of the clinical microbiology laboratory in recognizing a potential bioterrorism event. Laboratorians who have had specific training about bioterrorism will have a higher index of suspicion, which will make it easier for them to overcome what may be the biggest obstacle to recognizing an event—reluctance to consider a bioterrorism event as a possible explanation for anomalous test results.

Event recognition within the health care facility can resemble an epidemiological investigation. Case definitions must be made and then followed by aggressive case finding. Event recognition is thus a team effort. Effective channels of communication must be in place between clinicians and the microbiology laboratory. Health care providers should enhance their ability to recognize syndromes that suggest a bioterrorism-related incident, since clinicians, particularly infectious disease physicians, will be central to recognizing the initial stages of an incident. Two to three days later, laboratorians may recognize certain culture isolates as indicative of an event. If each group informs the other of their suspicions, it will facilitate a successful investigation.

In the event that a suspicious agent is detected, the first concern of the laboratory, as always, should be to notify the treating physicians of test results so that they can initiate appropriate management of patients. To allow evaluation of any potential threat to the wider community, the laboratory should then promptly alert institutional infection control personnel and institutional leadership. Infection control personnel will notify county and state public health officials that an outbreak of an unusual illness has occurred. It is the external public health authorities who will determine whether a threat to the general public health exists and who will recommend whether patient specimens or isolates should be forwarded to higher-level laboratories for further analysis and, if warranted, notify law enforcement agencies.

Even when an isolate is identified as an organism that is on the list of potential agents of bioterrorism, that is not evidence that a bioterrorism event is under way. For several pathogens on the list, including Francisella tularensis, Brucella spp., and Yersinia pestis, a low background rate of sporadic infections occurs by endemic transmission, at least in certain areas of the country. As noted above, a bioterrorism event will most probably be characterized by a geographic cluster of infections with the same organism. Neither is a biocrime eliminated because an organism is not on the list of potential agents of bioterrorism. Any pathogen can be misused, as illustrated by the use of Salmonella in The Dalles, Oregon. Determination of a true event is done by public health officials and legal authorities.

Many other criteria may be used to determine whether a threat to the public health exists. For instance, a bioterrorism event may feature an increase in the number of particular infections over the background level. (For this reason, all laboratories need to know the prevalence of these diseases in their communities, information that is available in state and federal disease reports.) Another possible signal is an occurrence of nonendemic disease, such as pneumonic plague in an area endemic for plague or any type of plague in a nonendemic area. In general, a mental flag should go up when seeing an organism that is not usually found in this geographic location, in this body site, or at this time of the year. If Yersinia pestis is isolated in Arizona, the flag does not go up, but in Maine it should. If influenza is seen in the summer rather than in the winter, that should trigger suspicion, and a single confirmed case of smallpox would indicate a bioterrorism attack. Outbreaks of infections in animal populations or an outbreak of a reportable disease can signal a bioterrorism event. Anything that is considered an outbreak, from an infection control or public health standpoint, should be scrutinized to see if it is a bioterrorism event.

During the process of determining whether a threat to the general public health exists, area clinical microbiologists should be available and called on to serve in an advisory capacity.

To facilitate communication of information and specimens, it is critical for each state to make available to each hospital laboratory and commercial laboratory a list of contacts, phone numbers, and locations of state and federal laboratories with 24-hour/7-day contact numbers.

While we are primarily focused in this document on the public health implications of a bioterrorism incident, it is important to note that bioterrorism is a legal term, defined as the intent to use or the use of bacteria, viruses, or toxins to cause harm to people, animals, or agriculture. Under Presidential Decision Directive 39, the FBI has the responsibility to declare when a bioterrorism event has occurred.

Recognizing a potential bioterrorism agent

The clinical microbiology laboratory is more an organism recognition site than an event recognition site. To facilitate recognition of bioterrorism-related isolates, laboratories must have qualified personnel conducting their testing. Personnel working with cultures may require specialized training to recognize isolates that are most likely to be used in a bioterrorism attack, particularly in rural areas where laboratory supervisors and directors may not be readily available and especially in rural areas where certified microbiology specialists may not be readily available. In this way, rarely encountered microorganisms can be correctly identified.

Clinical microbiology laboratories have access to the Laboratory Response Network (LRN), a system created by CDC to provide an organized response for the detection and diagnosis of biological agents. (To increase the effectiveness of the LRN, efforts should be made to get small hospital laboratories and commercial laboratories involved as well.) In principle, all laboratories are assigned to one of four categories (A-D) that outline their responsibilities during presumptive bioterrorism events. Level A laboratories (primarily laboratories in hospitals and clinics, as well as small public health laboratories) can handle clinical specimens for the most likely potential bacterial agents of bioterrorism and can do clinical diagnostic cultures for four of these agents: Bacillus anthracis, Yersinia pestis, Francisella tularensis, and Brucella spp. Their key responsibilities are to be familiar with the likely agents of bioterrorism and to be prepared to use the Level A laboratory algorithms designed to rule out these agents (discussed below).

With these algorithms, Level A laboratories use minimal criteria to rule out bioterrorism-related microorganisms and refer suspicious isolates to a higher-level laboratory. Whenever an agent is recognized or even suspected as being an organism requiring handling at a higher safety level, the culture and its preliminary test plates and tubes should be transferred immediately to a Class II biosafety cabinet and the supervisor should be notified of the potential biosafety hazard. For Level A laboratories, shipment of the specimen to a higher-level laboratory would be appropriate at this point.

In some situations, the Level A laboratory (with Biosafety Level 2 [BSL-2] capacity) may be the first to become suspicious that one of the critical agents has been isolated and would therefore respond according to the local institutional plan.

Level B laboratories (with some BSL-3 capacity) can confirm the identification of suspicious isolates and determine their antimicrobial susceptibility. Level C laboratories (with optimal BSL-3 capacity) can use molecular methods and typing procedures and perform toxigenicity testing of suspicious isolates. Level D laboratories, which are located at the Centers for Disease Control and Prevention and at the U.S. Army Medical Research Institute of Infectious Diseases, are capable of high-level characterization of bioterrorism isolates, such as smallpox virus and viral hemorrhagic fever viruses in BSL-4 facilities. They are also proficient in searching for a wide range of biological and chemical agents in clinical and nonclinical specimens.

All laboratories should adhere to the safety precautions that have been defined for the category to which they have been assigned.

Widely used, commercially available identification systems utilized by clinical microbiology laboratories in routine daily operations do a poor job of identifying microorganisms associated with bioterrorism, such as Francisella tularensis, Brucella spp., and Bacillus anthracis. For this reason, representatives from the American Society for Microbiology (ASM) and the Centers for Disease Control and Prevention (CDC) recently devised screening algorithms involving the use of eight easily performed biochemical tests to rule out five high-priority bioterrorism agents. These protocols are available on the web at www.bt.cdc.gov. Screening algorithms for additional potential bioterrorism agents are being developed. As stated above, Level A laboratories are expected to perform these tests to rule out bioterrorism pathogens. We recommend that CLIA on-site surveys include documentation of laboratory bioterrorism preparedness by measuring proficiency in the use of these algorithms. The economic impact of readying all laboratories for performance of the Level A algorithms needs to be determined. The American Society for Microbiology's Committee on Laboratory Practices should work with other laboratory-oriented professional organizations to publicize the Level A algorithms.

Ultimately, rapid detection methods will be important in identifying potential bioterrorism agents, especially during an overt event when the agent is announced. Such molecular-based rapid detection methods are now under development (see Optimal methods for agent detection in the section Research Issues).

Impact of a bioterrorism event on the clinical laboratory

Clinical microbiology laboratories must have a Bioterrorism Preparedness Plan—which will be part of a hospital-wide protocol—and be ready to enact it in the event of a suspected bioterrorism event. The plan should contain provisions that address the following situations, which could well occur in a real or suspected bioterrorism incident:

  • A flood of specimens for laboratory analysis may quickly deplete available supplies and reagents. A contingency plan for acquiring supplies rapidly from manufacturers or other clinical microbiology laboratories should be in place.
  • A plethora of specimens either from persons actually affected by a bioterrorism agent or from the worried well could overwhelm laboratory testing capacity.
  • The laboratory must know the identity and location of an appropriate higher-level laboratory to which they will transport specimens or agents for confirmatory testing. Training programs should cover the complexities of federal chain-of-custody documentation requirements.
  • Packaging for transporting specimens or agents safely to an appropriate higher-level laboratory may not be available in necessary quantities. A contingency plan for acquiring packaging materials should be devised.
  • Despite appropriate packaging, shipping companies may be reluctant to transport specimens or agents from a bioterrorism event. Public health authorities may have to arrange transport by other means.
  • Without appropriate education and training in the pathogenesis and transmission of these agents, laboratory staff may be fearful of working with specimens or isolates collected during a bioterrorism event. Fear may prevent them from coming to work. To reduce this fear factor, it is essential to maintain category-specific safety standards in the laboratory and to provide ongoing education programs to reassure employees and to keep them informed. Segregation of bioterrorism-related testing from routine laboratory testing is discouraged, unless specialized containment facilities are required for handling particular agents.
  • Post-exposure prophylaxis supplies and medications should be on hand within the institution for administration to individuals who may be exposed to agents before it is recognized that a bioterrorism event has occurred. Additional supplies should be available in a central location as part of a coordinated regional preparedness plan.
  • Demands for information from local and federal officials and the external news media can be expected to reach the laboratory. Information that is released should come from institutional public relations personnel or public health authorities, and not directly from the clinical microbiology laboratory. Laboratory personnel should refer all requests for information to a designated spokesperson.

Deciding whether a laboratory has the capacity to handle an event

All Level A laboratories should be prepared to participate in the initial handling of a bioterrorism event to the degree consistent with the biosafety level that they have been assigned within the LRN. When a bioterrorism event is suspected, the laboratory's Bioterrorism Preparedness Plan should be enacted immediately, with the laboratory director, who is responsible for safety, making decisions about the laboratory's capacity to handle individual specimens about which there may be questions. Laboratory directors should know the nearest LRN laboratory to which they can send cultures for confirmatory identification or specimens if they cannot respond to a request. As time passes, clinical microbiologists and institutional administrative personnel together should monitor the situation in the laboratory and throughout the institution and determine whether changes in the level of participation are indicated.

Assessing risk to laboratory personnel

The primary risk to laboratory personnel from a bioterrorism agent is inhalation of aerosolized agents during routine identification, particularly with Francisella tularensis and Brucella spp. Risk assessment is the responsibility of clinical microbiologists, infection control personnel, and infectious disease physicians. Risk assessment should be conducted on at least an annual basis, and a risk analysis checklist to gauge laboratory preparedness should be developed. It is assumed that the laboratory is currently practicing standard precautions when handling body specimens to provide a barrier against exposure to blood and body fluids. Use of universal precautions during daily laboratory operations is prudent, since there may be no suspicion of increased risk when the first specimen of a bioterrorism agent enters the laboratory. Reducing the risk to laboratory personnel from potential bioterrorism pathogens will provide greater safety in normal operation as well, since some of the agents that could be used in a biocrime may be occasionally isolated in clinical laboratories within the U.S. in the absence of any biothreat.

Use of agent-appropriate containment facilities, particularly a Class II biological safety cabinet, to contain aerosols. Standard infection control precautions should adequately protect laboratory personnel against most biohazards. The question of disinfection of laboratory instrumentation inadvertently exposed to bioterrorism agents during routine laboratory work needs to be addressed. The ASM Committee on Professional Affairs should participate in this effort.

When it is realized that a technologist may have been exposed to a bioterrorism agent, a local infection control professional would institute the preapproved postexposure plan, which may consist simply of a fever watch or may also include prophylaxis and vaccination.

A number of issues regarding laboratory worker safety remain to be resolved. Guidelines are needed for how to assess risk in the clinical microbiology laboratory. Resources need to be made available to smaller laboratories that may not have ready access to an infectious disease consult. Since any agent can be used in a bioterrorism event, all recommended vaccination practices should be maintained.

Finally, there is the question of how specimens that may contain smallpox or other highly virulent viruses should be handled. When a specimen is suspected to contain either smallpox virus or one of the agents of viral hemorrhagic fever (e.g., Ebola, Marburg, or Junin), it should not be managed in any of the Level A laboratories. The Centers for Disease Control and Prevention and the state public health laboratory should be contacted immediately, and safe transport of the specimen should be arranged.

Of greater concern is the circumstance in which a specimen is submitted to the hospital virology laboratory for viral studies, but no bioterrorism agent is suspected or mentioned on the test order form. Smallpox virus will grow and amplify in most of the routine cell lines that are employed for herpesvirus and varicellazoster virus cultures. Once amplified, the agent would present an even greater threat. A laboratory technologist may neither suspect nor recognize a hazard. Failing to obtain a positive fluorescent stain for one of the more common viruses, the technologist may pass or manipulate the culture multiple times before abandoning the effort, increasing the risk of becoming exposed should the specimen actually contain smallpox virus. How to recognize and safely manage such circumstances is a critical conundrum.

Defining the role of the clinical microbiology laboratory in preparing for a potential act of bioterrorism

Both laboratory and institution-wide response plans must be developed. Those plans must contain:

  • Lists of safety measures to enact, including use of personal protective equipment.
  • Communication protocols that should be followed, including “call lists” of key personnel to be notified.
  • Contact and location information for the nearest Level B/C LRN laboratories.
  • Agent identification protocols to be used in the laboratory.
  • Ongoing training program descriptions to ensure readiness of personnel.
  • Measures to ensure security, including limiting access to reference cultures, isolates, etc. (see next section).
  • Steps for transportation of specimens.

Access to patient isolates

As with any patient isolate, access to patient isolates during an actual or suspected bioterrorism event should be extremely limited. Within the laboratory, access should be available only to CLIA-qualified individuals appropriate for the agent, with the laboratory director's approval.

Outside persons who will have access to isolates include workers at Level B, C, and D laboratories, as well as personnel from the FBI, if isolates are needed as evidence in a criminal investigation. Researchers can gain access with appropriate approval.

To limit access to qualified individuals, all laboratories should save bioterrorism event-related specimens and isolates in a secure area that will prevent janitors, engineering staff, and other nonqualified service workers from gaining access.

Even in the absence of an actual or suspected bioterrorism event, access to agents on the list of potential bioterrorism organisms should be limited. Clinical laboratories should know what organisms they have stored in their freezers and should be aware of the Select Agent Rule and ensure that they are in compliance (see Appendix).

Safety issues regarding specimen shipping and handling and disposal of bioterrorism agents

Packaging and shipping criteria are the same for all biologic agents, including potential agents of bioterrorism. These criteria can be found in the section on transportation and transfer of biological agents in the manual Biosafety in Microbiological and Biomedical Laboratories. One recent change in these criteria is that both clinical specimens submitted for infectious disease analysis and pure cultures of infectious disease isolates are now considered “infectious substances” and must display an “infectious substances” label.

Specimens and agents must be shipped according to IATA (UN 6.2 packaging) packaging regulations. All intrastate specimens should be packaged in the same way as for interstate shipping.

Laboratory personnel must know how to package and transport these critical agents to another site for further analysis. Use of this packaging standard requires specialized training that should be offered to laboratory personnel. Perhaps an ASM-sponsored workshop could be organized to assist with the training effort. At least one set of the packaging materials should be maintained in laboratories at all times.

Because the packaging materials are expensive (approximately $50 each), the question of who covers the supply costs must be addressed.

Laboratory directors should know which carriers will take clinical specimens. Most would be sent to the state public health laboratory, which should first be notified that a specimen possibly containing an agent on the list of potential bioterrorism agents is coming.

An important safety issue is that most shippers, including United Parcel Service (UPS) and Federal Express, have no procedure for safety if the package is damaged. They still deliver the package. Only the United States Postal Service (USPS) has a policy to call CDC. In the case of a true bioterrorist release of an agent, the FBI will require that a chain-of-custody protocol be initiated and may facilitate transport of the specimen.

In addition to shipping, clinical microbiology laboratories should make provision for adequate disposal of specimens containing potential bioterrorism agents. Currently many clinical laboratories don't have autoclaves and send viable agents off site for disposal. Handling and disposal of medical waste in a “medically secure” manner are a financial issue for many institutions. Sending samples off site for disposal raises concerns about increasing access to agents for potential bioterrorists and about creating a risk of infection among those handling laboratory waste. In this regard, it is important to note a recent article in the Journal of the American Medical Association (JAMA) that highlighted Mycobacterium tuberculosis cultures as a source of infection in waste handlers. We recommend that specimens possibly containing potential bioterrorism agents and other BSL-3 agents (and associated waste) be autoclaved (or incinerated) on site before disposal.

Role of the clinical microbiologist

Level of expertise required in the laboratory to carry out responsibilities in the event of a bioterrorism event

Clinical microbiologists certified by the programs of the American College of Microbiology possess the necessary expertise to use standardized protocols to rule out microorganisms associated with a bioterrorism threat and to forward suspicious specimens and isolates to the next higher laboratory. Certification is available for individuals with bachelor's and master's degrees (National Registry of Microbiologists) and doctoral degrees (American Board of Medical Microbiology and the American Board of Medical Laboratory Immunology). Individuals certified by other professional organizations in the area of clinical microbiology (e.g., American Society of Clinical Pathologists, American Board of Pathology, and American College of Internal Medicine) might have adequate expertise as well.

Unfortunately, at the present time, the United States is experiencing erosion in the level of expertise of personnel working in clinical laboratories. All clinical microbiology laboratories should be staffed with individuals who have been trained to comply fully with BSL-3 safety requirements in order to safely handle bioterrorism agents as well as those organisms associated with emerging infections. There is no substitute for an on site qualified microbiologist at the level of CLIA technical supervisor in identifying bioterrorism agents. In addition, expertise is needed in the ability to monitor trends in isolating and identifying critical agents.

Personnel standards that guarantee qualified workers in the laboratory to respond to a bioterrorism event

Individuals in clinical microbiology laboratories who are responsible for identifying microorganisms and testing them for antibiotic susceptibility should possess at least a bachelor's degree in medical technology or a life science field that includes at least 20 credit hours in microbiology coursework. Personnel standards in the CLIA 1988 legislation should be amended to raise the minimum education standard for this group of laboratory workers from an associate degree to a bachelor's degree.

In addition, every clinical microbiology laboratory should have ready access to a clinical microbiologist certified either as a specialist (by the National Registry of Microbiologists or the American Society of Clinical Pathologists) or certified at the doctoral level (by the American Board of Medical Microbiology, American Board of Medical Laboratory Immunology, American College of Internal Medicine, or American Board of Pathology). Not only should professional microbiologists meet minimum education and certification standards, they should participate in continuing education to ensure that competence is maintained.

Bioterrorism-specific training should take place as part of the ongoing qualification of microbiologists. Training in recognizing and responding to a possible bioterrorism event that is expressly designed for the clinical microbiology laboratory is needed, since there is a disconnect between the training offered by the first-responder community and that needed by the clinical laboratory community. We recommend that ASM be involved in curriculum development and training and that they partner with the National

Laboratory Training Network. Bioterrorism training should include safety education, bioterrorism awareness training, and familiarity with Level A screening protocols and may be carried out by state public health personnel. For instance, teams composed of a local microbiologist and a local public health worker could hold community meetings of short duration that are promoted as meetings on expansion of surveillance and preparedness for detecting and managing emerging infections and epidemics.

Each clinical microbiology laboratory, whether in a hospital, clinic, or commercial setting, should develop a Bioterrorism Preparedness Plan and communicate it to all employees. Outcome measures to assess competency should be an integral part of the Plan and should be included in competency assessments.

Communication of a bioterrorism event

Internal communication in the event of a bioterrorism event

In general, the process of internal (intralaboratory) communication should follow the approved bioterrorism response plan of the institution and should include notification of the laboratory director by clinical microbiology laboratory staff. It will then be the laboratory director's responsibility to notify key individuals within the institution and external to the institution.

More specifically, in the event that a critical agent is isolated, the chain of communication goes from technologist to supervisor to laboratory director. When a bioterrorism threat agent is suspected, the laboratory director will notify the clinician (physician of record) as well as the infection control professional. In commercial laboratories, the technologist notifies the manager, who in turn notifies the clinician of record. A safety officer is then notified, who will do a risk assessment and notify senior management.

When an actual bioterrorism event is suspected, the first step is for the authorities to determine the reliability of the information. Technologists should be notified that a biocrime may have occurred; they should be aware bioterrorism specimens may come in. The laboratory supervisor and/or director should review pertinent procedures with technologists.

External communication in the event of a bioterrorism isolate

The laboratory director should ensure that clinicians caring for affected patients, infection control personnel, institutional infectious disease physicians, designated members of the institutional administrative staff, and appropriate public health authorities are notified promptly in the event of a suspected bioterrorism isolate.

In addition to transmitting information, clinical microbiology laboratories will have to transmit specimens and cultures suspected of containing a bioterrorism agent. Level A laboratories should send specimens and cultures to the nearest Level B/C laboratory for confirmation. Laboratories receiving specimens from multiple jurisdictions should send specimens and isolates to the nearest Level B/C laboratory for confirmation and report to the state epidemiologist where each specimen came from. Once the Level A laboratory's finding on a culture is confirmed or not confirmed, the Level B/C laboratory will notify the sending laboratory, which will notify the clinician who submitted the sample. Level B/C laboratories are also responsible for notifying the state epidemiologist and laboratory director when identification of a suspect bioterrorism agent is confirmed.

The ensuing epidemiologic investigation will help to determine whether a current problem is a natural outbreak or an intentional release. If an intentional event is suspected, public health officials will call the FBI, which will declare a bioterrorism event and manage external communication with the press.

In all situations and at all times, whether a possible bioterrorism agent has been isolated or an actual event is suspected, the institution should have an individual or office to serve as a single point of contact with the press.

Appropriate and effective methods of communication

Direct and secure channels of communication are mandatory. Telephone conversation over a landline is an example of appropriate and effective communication. Conversations in public areas, unencrypted e-mail, cellular telephones, and facsimile machines in unsecured locations, while effective, are inappropriate.

Maintaining patient confidentiality

Whether or not a clinical situation involves a possible bioterrorism agent, patient names and results should never be released to unauthorized individuals. Moreover, the patient confidentiality provisions contained in the 1996 Health Insurance Portability and Accountability Act (HIPAA) regarding electronic data interchange should be strictly observed. In addition to curtailing use of the unsecured channels of communication described above, the issue of password-governed access to information within institutional information systems must be addressed.

Ethical considerations with regard to effective communication

Our primary ethical consideration is to be ever mindful of patient confidentiality during the communication process. Dissemination of patient information should be limited to a need-to-know basis and done only by authorized individuals. While protecting patient confidentiality, it is mandatory for the responsible person in the clinical microbiology laboratory to maintain the public health by reporting results indicating a possible bioterrorism isolate to the state epidemiologist.

We have an additional ethical obligation to our laboratory staff and other health care workers. If a communicable disease is detected, we should notify the institution's infection control professional, who will identify individuals who may have examined the patient or handled specimens from that patient and inform them that they may have been exposed to an agent.

Research issues

Defining practical methods for the detection of bioterrorism agents

The Basic Protocols for Level A Laboratories, recently promulgated by the combined efforts of the American Society for Microbiology and the Centers for Disease Control and Prevention, offer standardized, practical methods that raise suspicion of an isolate being one of the organisms on the bioterrorism agent list and that can be performed in the clinical microbiology laboratory. As noted above, Level A laboratories are asked to rule out, not identify, bioterrorism agents. These basic protocols, or flowcharts, allow the laboratory to rule out critical agents and to refer specimens if potential bioterrorism agents cannot be ruled out. Clinical laboratories should not use “rapid” hand-held assays that are being marketed to first responders to detect potential bioterrorism agents, since they are currently configured for environmental specimens. Only FDA-cleared assays should be used.

Beyond the simple tests employed in the basic protocols, advanced methods now available to aid identification of possible bioterrorism agents include phage typing and direct fluorescent antibody (DFA) for Bacillus anthracis and phage typing for Yersinia pestis.

Optimal methods for agent detection

At the present time, optimal methods for Level A laboratories are the currently approved basic protocols developed by the CDC and by ASM. They present no added cost to the laboratory, with the exception of a urea tube.

For Level A laboratories, it would be optimal to have improved databases for automated microbiological systems that now have difficulty identifying fastidious microorganisms, including bioterrorism agents. Unfortunately, vendors have so far been reluctant to work toward this goal and may need encouragement to cooperate. Short of this, companies should be encouraged to adjust their databases to provide no answer rather than incorrect answers.

Looking toward the future, optimal methods would include immunodiagnostic assays that are rapid (<24-hour turnaround time), easy to perform, and accurate for pre- and post-cultural analysis of specimens or isolates. Due to the limited demand for this type of testing in Level A laboratories, however, these assays would probably be most appropriate for use in Level B and C laboratories.

Nucleic acid detection assays should also be developed, validated, and made available to Level B/C laboratories.

Analysis of the fatty acid composition of cell membranes has shown promise in differentiating microorganisms that could be used in a bioterrorism attack and deserves further investigation. The specificity of this technique may enable rapid strain recognition of possible bioterrorism agents.

Microsequencing of nucleic acids from potential bioterrorism agents should also be explored.

Possible restrictions on the acquisition and use of reference/patient material

With regard to specimens and cultures related to possible infections with potential bioterrorism agents, the Select Agent Rule may apply. Under this regulation, a site must be registered and must demonstrate that it has appropriate biosafety level facilities to handle the particular agent. In addition, approval (or exemption) by the institution's Institutional Review Board (IRB) may be required for use of patient specimens.

For some time now, it has been difficult to acquire materials needed to prepare control samples for laboratory assays of potential bioterrorism agents. The option of purchasing materials from clinical laboratories may be in jeopardy due to new regulations from the Food and Drug Administration requiring informed consent from patients before patient materials are used for this purpose. We recommend that ASM provide scientific advice to Congress to prevent unreasonable regulations on acquisition of patient samples. It would also be helpful to list necessary exemptions from IRBs, especially in cases where samples are blinded to the patient record.

Remaining questions regarding potential bioterrorism agents

We believe that there is a real question as to whether physicians or clinical microbiology laboratories will be able to detect the first case of smallpox in a bioterrorism event. Indeed, the diagnosis of smallpox is clinical, not laboratory based. Since smallpox has been eliminated in the U.S., very few primary care physicians would recognize a case of this illness. We recommend that smallpox be put back into the course curriculum for medical students and clinical microbiologists.

Laboratories that use rapid methods for viral diagnosis may not be able to follow the Level A protocols for an unknown virus. We need to define an effective alternative approach for these laboratories.

Beyond identifying the current most likely agents of bioterrorism, there are several microbiological goals that we should strive to attain in the next few years. We should develop the capability to detect genetically engineered organisms, both those that simply contain drug resistance genes and those that represent chimeras constructed from substantial segments of genetic material from more than one organism. In addition, we need to have the means for rapid detection of antimicrobial resistance.

Other laboratory safety issues that require investigation include actions that we need to take to protect clinical laboratory workers. For instance, what level of vaccination is required at Levels A, B, and C? Are universal precautions sufficient for all agents?

Research to determine the efficacy of disinfectants and germicidal agents against bioterrorism pathogens requires additional funding and elucidation by laboratories equipped to do these studies. Possible risks associated with contamination of laboratory equipment that occurs before a bioterrorism event is recognized need to be addressed, as do the best approaches toward elimination of agents from expensive laboratory equipment.

We also need to define more rigorously how veterinary, food, and water microbiology laboratories fit into the national bioterrorism preparedness plan. Tremendous expertise is available in these laboratories that could enhance the identification and investigation of bioterrorism events.

Finally, it would be helpful to have solid data on some practical issues related to existing elements of bioterrorism preparedness:

  • Review and update the extent of implementation of the training network in the Level A, B, and C laboratories and the military.
  • Develop data on the safety of current transport practices.

Education, training, and proficiency testing

Proficiency testing programs should be required for clinical microbiology laboratories that work with bioterrorism agents

The proficiency testing program administered to most clinical microbiology laboratories by the College of American Pathologists (CAP) could be modified to include regular ungraded challenges of attenuated (e.g., vaccine) strains of potential bioterrorism agents. It would be helpful for CAP and the American Type Culture Collection (ATCC) to collaborate to develop noncontagious strains for proficiency testing. For the testing sites, the primary purpose of these challenges would be educational. However, such challenges would also generate important data as to the readiness of clinical microbiology laboratories to detect a bioterrorism event and the efficacy of methods used by microbiology laboratories for detection and identification of agents. Such testing could also validate the utility of the Level A laboratory protocols for ruling out bioterrorism agents.

Full-scale proficiency testing programs for Level A laboratories are desirable and could be conducted by organizations that already perform proficiency testing in other areas, such as CAP, CLIA, and JCAHO. Such programs would include written sections as well as a practicum in identifying agents that would need to be ruled out when analyzing a specimen suspected of containing a bioterrorism microorganism. (Potentially confounding bacteria might include atypical Haemophilus, Bacillus megatherium, etc.) Commercial laboratories should save look-alike microorganisms for proficiency testing programs, an initiative that could be coordinated through CAP or any other organization that conducts a proficiency testing program. All certifying agencies governing hospitals and laboratories should add a question(s) regarding bioterrorism readiness.

The Centers for Disease Control and Prevention is developing a proficiency testing program designed for Level B and C laboratories. Proficiency testing for Level B and C laboratories will consist of fixed smears, specimens, and agents as appropriate for each laboratory's status in LRN. Challenges would validate the ability of these laboratories to confirm the identifications of bioterrorism agents.

Personnel competency measures that should be applied to those working on bioterrorism agents in the clinical microbiology laboratory

For Level A laboratories, the CLIA-mandated annual competency assessment of personnel should suffice. This requirement can be fulfilled by observing and documenting at-the-bench performance, by assessing technologist-specific performance on proficiency test challenges, or by showing satisfactory performance on written examinations. Ideally, outcome measures should be included in a competence assessment. Criteria for competency may include the ability to follow LRN guidelines, achieve correct results on proficiency tests, knowledge of when and to whom to report test results, and knowledge of potential bioterrorism organisms and their characteristics.

Special training required for a clinical microbiology laboratory to respond appropriately to a bioterrorism threat or event

Special training is required for a clinical microbiology laboratory to be able to respond appropriately to a bioterrorism threat or event. Topics that might be covered in such training are listed in the previous section. Additional topics might be knowledge of emergency procedures and knowledge of where to send environmental specimens and who to contact before sending the specimens.

Targeted training for personnel in Level A laboratories should be at least an annual event and could be presented as continuing education. Level A laboratory training is now available as a Power Point presentation on the website of the Association of Public Health Laboratories and should also be posted on the ASM website.

The National Association for the Accreditation of Clinical Laboratory Scientists, responsible for accrediting medical technologist training programs, should add bioterrorism training to their checklist for surveying training programs. In this way, new medical technologists would already have a knowledge base upon which to draw as they enter the laboratory work force. Continuing education programs on bioterrorism could be offered by groups, such as the American Society for Microbiology at its national meeting, local branches of the American Society for Microbiology at their meetings, regional clinical microbiology societies, and the American Society of Clinical Pathologists, to reach a broad audience of clinical microbiologists. Bioterrorism teleconferences, sponsored by groups like the American Society for Microbiology, the American Society of Clinical Pathologists, and the National Laboratory Training Network, could augment this effort.

Role for the American Society for Microbiology in assisting clinical microbiology laboratories to prepare for a bioterrorism event

As mentioned previously, one major step that ASM should take is to facilitate the rapid development of effective continuing education programs and materials by ensuring accuracy of curriculum materials and partnering with other agencies. In addition to this and other activities described earlier in this document, the Society can play a pivotal role in assisting clinical microbiology laboratories in the following ways:

  • The Committee on Postdoctoral Education Programs within the American College of Microbiology should add a module on bioterrorism to the areas covered by its approved training programs.
  • Foundation for Microbiology lecturers should be identified who can speak at local American Society for Microbiology branch meetings on the topic of bioterrorism preparedness.
  • ASM could sponsor an American Society for Microbiology representative to attend meetings of the College of American Pathologists Microbiology Resource Committee. One charge for this individual would be requesting inclusion of attenuated bioterrorism agents among proficiency test challenges.
  • Through its Committee on Laboratory Practices, ASM should urge that all clinical microbiology laboratories handle and process patient specimens within a laminar flow safety cabinet.

Awareness training for non-microbiology personnel

Special training should be provided to all nontechnical individuals who might work in the clinical microbiology laboratory or who might handle specimens during a possible bioterrorism event. Awareness training should be provided, for instance, to receptionists, janitors, maintenance staff, shipping personnel, warehouse workers, and security. In addition, training would be advisable for any public relations person who might act as a designated source of information during a suspected event. These activities should be part of the institutional preparedness plan.

Recommendations

Colloquium participants repeatedly emphasized the primary importance of the Level A clinical microbiology laboratory in serving as a sentinel for detecting these critical agents. Unlike with nuclear or chemical weapons, first responders to a bioterrorism event will most likely be clinicians and clinical microbiologists, especially in the case of an event without an overt signal. Rapid recognition of potential bioterrorism agents by Level A clinical microbiology laboratories will be essential for the public health response to a bioterrorism event. In conjunction with state and federal agencies, clinical microbiology laboratories will play an important role in determining when a bioterrorism event has occurred.

At the present time, however, there is an acute shortage of clinical microbiologists trained to respond effectively to emerging infections, including bioterrorism events. For these reasons, colloquium participants identified as their first priority a major initiative in education and training of clinical microbiologists, which would include upgrading both general microbiology skills that bear on identifying a bioterrorism threat and skills directly related to detecting and responding to a bioterrorism event. As part of this education and training effort, they formulated several recommendations:

  • Individuals in clinical microbiology laboratories who are responsible for identifying microorganisms and testing them for antibiotic susceptibility should possess at least a bachelor's degree in medical technology or a life science field that includes at least 20 credit hours in microbiology course-work. (In the absence of a bachelor's degree, an equivalent combination of training and experience is recommended, such as an associate (MLT) degree and ≥10 years of experience in a clinical microbiology laboratory.)
  • Consideration should be given to amending personnel standards in the CLIA ‘88 legislation to raise the minimum education standard for this group of laboratory workers from an associate degree to a bachelor's degree.
  • Bioterrorism-specific training should take place as part of the ongoing qualification of microbiologists at all levels.
  • All clinical microbiology laboratories should be staffed with individuals who have been trained to safely handle bioterrorism agents as well as those organisms associated with emerging infections.
  • Every clinical microbiology laboratory should have ready access to a clinical microbiologist certified either as a Specialist by an approved accreditation program (e.g., by the American College of Microbiology or the American Society of Clinical Pathologists) or certified at the doctoral level by an approved accreditation program (e.g., American Board of Medical Microbiology, American Board of Medical Laboratory Immunology, American College of Internal Medicine, or American Board of Pathology).
  • Professional microbiologists should be familiar with the likely agents of bioterrorism and be prepared to use the Level A laboratory algorithms designed for the detection of these agents.
  • Technologists working with cultures may require specialized training to recognize isolates that are most likely to be used in a bioterrorism attack, especially in rural areas where laboratory supervisors and directors may not be readily available.
  • The American Society for Microbiology (ASM) should be involved in bioterrorism-specific training, possibly in partnership with an organization such as the National Laboratory Training Network.
  • ASM should promote the rapid development of effective continuing education programs and materials by ensuring accuracy of curricula and materials and partnering with other agencies.

To evaluate the effectiveness of the recommended training, proficiency testing should be instituted. The proficiency testing program administered to most clinical microbiology laboratories by the College of American Pathologists (CAP) could be modified to include regular ungraded challenges of attenuated (e.g., vaccine) strains of potential bioterrorism agents. Full-scale proficiency testing programs for Level A laboratories are desirable and could be conducted by organizations that already perform proficiency testing in other areas. Such programs would include written sections as well as an exercise in identifying agents that would need to be ruled out in the event of a suspected bioterrorism threat. We recommend that CLIA on site surveys include documentation of laboratory bioterrorism preparedness by measuring proficiency in the use of Level A laboratory algorithms designed to rule out these agents.

Formal education and training are the first steps in qualifying a laboratory to respond to a possible bioterrorism threat. To translate fundamental skills into practical action, planning is necessary. Therefore, all clinical microbiology laboratories should have a bioterrorism response plan. Minimal elements of a response plan include knowing the chain of communication within the laboratory when a possible bioterrorism agent is suspected; where to send specimens for further testing after an initial screening protocol suggests the presence of a potential bioterrorism agent; and how to respond if the laboratory becomes overwhelmed with samples during a suspected or actual bioterrorism event. Maintaining patient confidentiality would also be an important component of a response plan. Laboratory personnel should be evaluated annually on their knowledge of the bioterrorism response plan.

No matter how well trained and prepared, personnel in the clinical microbiology laboratory can only be effective guardians of the public health as part of a network of laboratories, epidemiologists, and infectious disease specialists. The Laboratory Response Network is the essential underpinning of the capability to respond to a bioterrorism threat, with state public health laboratories assuming a crucial role in the Network. Continued support of the Laboratory Response Network is therefore necessary to ensure rapid response to a possible bioterrorism event. At the current time, the system for responding to bioterrorism events in the U.S. is better developed than ever, but it is still inadequate. All of the pieces necessary to respond to a bioterrorism event at the advanced level are in place. What is needed is enhancement of the existing system at the sentinel level—the Level A clinical microbiology laboratory. Additional education and training need to be provided at the sentinel level to ensure optimal functioning of the Network.

In a broader context, the Network could be enhanced in several ways. It is important that there be better coordination and less redundancy among local, state, and federal agencies involved in bioterrorism preparedness. We also need to define more rigorously how veterinary, food, and water microbiology laboratories fit into the national bioterrorism preparedness plan. Finally, to facilitate communication of information and specimens, it is critical for each state to make available to each Level A laboratory a list of state and federal laboratories with locations, names of contact persons and 24-hour/7-day contact numbers.

Several recommendations arose concerning laboratory safety. Assessment of risk to laboratory personnel from bioterrorism organisms is the responsibility of clinical microbiologists, infection control personnel, and infectious disease physicians. Risk assessment should be conducted on at least an annual basis. A risk analysis checklist should be developed to gauge laboratory preparedness.

We also recommend that potential bioterrorism agents and other Level 3 agents (and associated waste) should be autoclaved (or incinerated) on site before disposal. And, to increase the probability of being aware of specimens possibly containing smallpox, we recommend that information on recognizing the clinical manifestations of smallpox be restored to the course curriculum for medical students and clinical microbiologists.

To increase the ability of microbiology laboratories to detect potential bioterrorism agents rapidly and accurately, we recommend continued development of immunodiagnostic assays with <24-hour turnaround time for these pathogens. As well, it would be desirable to utilize nucleic acid detection assays for potential bioterrorism agents. In addition, Level A laboratories would benefit from improved databases for automated microbiological systems that now have difficulty identifying bioterrorism agents. Future efforts should be directed toward developing methods for detecting antimicrobial resistance and genetic alterations in microorganisms that could be used in bioterrorism attacks.

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Copyright 2001 American Academy of Microbiology.

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Bookshelf ID: NBK565023PMID: 33289984DOI: 10.1128/AAMCol.27Oct.2000

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