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WHO Best Practices for Injections and Related Procedures Toolkit. Geneva: World Health Organization; 2010 Mar.

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WHO Best Practices for Injections and Related Procedures Toolkit.

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Medical treatment is intended to save life and improve health, and all health workers have a responsibility to prevent transmission of health-care associated infections. Adherence to safe injection practices and related infection control is part of that responsibility – it protects patients and health workers.

What is a safe injection (1)

A safe injection, phlebotomy (drawing blood), lancet procedure or intravenous device insertion is one that:

  • does not harm the recipient;
  • does not expose the provider to any avoidable risk;
  • does not result in any waste that is dangerous for other people.

1.1. Unsafe injection

Unsafe injections can result in transmission of a wide variety of pathogens, including viruses, bacteria, fungi and parasites (2). They can also cause non-infectious adverse events such as abscesses and toxic reactions. Reuse of syringes or needles is common in many settings. It exposes patients to pathogens either directly (via contaminated equipment) or indirectly (via contaminated medication vials) (3, 4).The risks of unsafe injection practices have been well documented for the three primary bloodborne pathogenshuman immunodeficiency virus (HIV), hepatitis B virus (HBV) and hepatitis C virus (HCV). The estimated global burden of disease for the year 2000 from unsafe injection practices for these pathogens included (3):

  • 21 million HBV infections (32% of new HBV infections);
  • 2 million HCV infections (40% of new HCV infections);
  • 260 000 HIV infections (5% of new HIV infections).

These bloodborne pathogens also contribute to illness among health workers – an estimated 4.4% of HIV infections and 39% of HBV and HCV infections are attributed to occupational injury (5). Among susceptible health workers who do not receive post-exposure prophylaxis (PEP), the risk of infection after needle-stick injury is 23–62% for HBV and 0–7% for HCV (6). Infections may also be transmitted (to other health workers and to patients) from cross-contamination of health workers' hands, medications, medical equipment and devices or environmental surfaces. Thus, proper injection techniques and procedures contribute to the safety of both patients and health workers (1).

1.2. Purpose and scope

The purpose of this toolkit is to promote implementation of safe practices associated with the following medical procedures:

  • intradermal, subcutaneous and intramuscular needle injections;
  • intravenous infusions and injections;
  • dental injections;
  • lancet procedures.

The document complements and expands existing World Health Organization (WHO) guidelines and related materials (1, 7, 8). The toolkit describes:

Important terms related to injection safety are included in the glossary. Key reference documents are included in the CD-ROM and the reference list. All of these documents may be copied for training purposes, provided that the source is acknowledged.

1.3. Target audience

This toolkit is intended to be used to guide training and daily practice of all health workers in public and private health services. It is primarily aimed at workers who give injections or draw blood, and at those who handle medical waste. However, it will also be useful for health facility administrators, those responsible for infection-control policy and practice, and those responsible for procurement of injection equipment and other health-care supplies.

1.4. Bloodborne virus transmission

Risk of transmission of bloodborne infections depends on the particular pathogen and on the volume and type of blood exposure (911). Pathogens such as HBV, HBC and HIV (discussed below) may be transmitted in the absence of visible blood contamination.

Vector-borne diseases such as malaria can also be transmitted through blood, but require large volumes, such as are found in a blood transfusion. Infections transmissible by blood transfusion are covered in other documents on blood safety.

1.4.1. Hepatitis B virus

Newly acquired HBV infection is often asymptomatic – only 30–50% of children over 5 years of age and adults have initial clinical signs or symptoms (12, 13).The fatality rate among people with reported cases of acute symptomatic hepatitis B is 0.5–1.0 (13).

Chronic HBV infection develops in about 90% of those infected as infants, 30% of infected children under 5 years of age, and less than 5% of infected individuals over 5 years of age (12, 13). Overall, about 25% of those who become chronically infected during childhood, and 15% of those who become chronically infected after childhood, die prematurely from cirrhosis or liver cancer (12, 13).

There is no specific treatment for acute hepatitis B; treatment for chronic infection with HBV is costly and often not available.

HBV is transmitted by percutaneous or mucosal exposure to infectious blood or body fluids. Infections can also result from unnoticed exposures, such as inoculation into cutaneous scratches, lesions or mucosal surfaces (14). Hepatitis B surface antigen (which indicates chronic infection) has been detected in multiple body fluids; however, only serum, semen and saliva have been shown to be infectious (12).

HBV is most highly concentrated in serum, with lower concentrations in semen and saliva. The virus is comparatively stable in the environment and remains viable for 7 days or longer on environmental surfaces at room temperature (12). Among susceptible health workers, the risk of HBV infection after a needle-stick injury involving an HBV-positive source is 23–62% (5, 6, 14). Prompt and appropriate interventions with PEP measures can lessen this risk. However, the recommendation is to vaccinate health workers, including waste handlers, with hepatitis B vaccine. The vaccination should be given during pre-service training for those who did not receive it in childhood (see Chapter 4) (15).

1.4.2. Hepatitis C virus

Individuals with acute HCV infection are typically either asymptomatic or have a mild clinical illness. Antibody to HCV (anti-HCV) can be detected in 80% of patients within 15 weeks after exposure, and in 97% by 6 months after exposure (16). Chronic HCV infection develops in 75–85% of infected individuals (16).

Most people remain asymptomatic until onset of cirrhosis or end-stage liver disease, which develops in approximately 10–20% of infected individuals within 20–30 years (16). There is no specific treatment for acute hepatitis C; treatment for chronic HCV infection is costly and is often not available (17).

HCV is transmitted primarily through percutaneous exposures to blood, but transmission is less efficient than for HBV. HCV is viable in the environment for at least 16–23 hours (18, 19). The risk for transmission from exposure to fluids or tissues other than HCV-infected blood has not been quantified, but is expected to be low. Transmission rarely occurs from exposure to blood through mucous membranes or nonintact skin (16, 17, 20). The average incidence of anti-HCV seroconversion after accidental percutaneous exposure from an HCV-positive source is 1.8% (range: 0–7%) (16). Currently, there is no vaccine or effective PEP for HCV (see Chapter 4).

1.4.3. Human immunodeficiency virus

Transmission of HIV occurs through sexual contact, vertical transmission or blood exposure caused by unsafe blood transfusions, unsafe medical injection practices and the sharing of needles and syringes by injecting drug users (21).

HIV is less stable in the environment and less transmissible than either HBV or HCV. Potentially infectious materials include blood and body fluids, semen and vaginal secretions that are visibly contaminated with blood; other body fluids are considered less infectious. HIV causes a brief primary infection several weeks after exposure, and quickly becomes detectable by antibody tests. There is no cure for HIV infection, but antiretroviral treatment is increasingly available for acquired immunodeficiency syndrome (AIDS).

Exposures that pose a risk of transmission in occupational settings include percutaneous injuries, contact of mucous membranes, or contact of nonintact skin with potentially infected fluids (2, 6, 14, 22). The average risk for HIV transmission after a percutaneous exposure to HIV-infected blood has been estimated to be about 0.3% (95% confidence interval [CI]: 0.2–0.5%) and after mucous membrane exposure, approximately 0.09% (95% CI: 0.006–0.5%). Risk from nonintact skin exposure has not been quantified, but is estimated to be less than that for mucous membrane exposure. Guidelines for the use of antiretroviral PEP are discussed in Chapter 4.

1.5. Prevention strategies

Eliminating unnecessary injections is the best way to prevent injection-associated infections. Up to 70% of injections in some countries are medically unnecessary (23). When effective treatment can be given by other routes (oral or rectal), this is preferred, because it reduces potential exposure to blood and infectious agents, and thus reduces infection risks.

Vaccination of health workers with hepatitis B vaccine is important in protecting both health workers and patients.

Methods for reducing exposure and preventing infection transmission include hand hygiene, barrier protection (gloves), minimal manipulation of sharp instruments (including injection equipment), and appropriate segregation and disposal of sharps waste (note: sharps are items such as needles that have corners, edges or projections capable of cutting or piercing the skin) (Table 1.1).

Table 1.1. Examples of conditions causing risks in giving injections or collecting blood.

Table 1.1

Examples of conditions causing risks in giving injections or collecting blood.

Injections are unsafe when given with unsterile or improper equipment or technique. It is important to avoid contamination of injectable medications. Physically separating clean and contaminated equipment and supplies helps to prevent cross-contamination. For example, immediate disposal of a used syringe and needle in a safety box placed within arm's reach is the first step in safe waste management (1, 24).

Protection of health workers also requires a prompt response to and reporting of occupational exposures. Post-exposure management and prophylaxis is discussed in Chapter 3.

Injection safety is an important component of basic infection control. The concept of “standard precautions”, with mandatory safe practices, must be routinely applied in all healthcare settings, and every person in such settings should be considered a potential source of infection. Best practices for injection, the collection and handling of blood samples, and waste management are discussed in the following chapter.

Copyright © 2010, World Health Organization.

All rights reserved. Publications of the World Health Organization can be obtained from WHO Press, World Health Organization, 20 Avenue Appia, 1211 Geneva 27, Switzerland (tel.: +41 22 791 3264; fax: +41 22 791 4857; e-mail: tni.ohw@sredrokoob). Requests for permission to reproduce or translate WHO publications – whether for sale or for noncommercial distribution – should be addressed to WHO Press, at the above address (fax: +41 22 791 4806; e-mail: tni.ohw@snoissimrep).

Bookshelf ID: NBK138493
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