Study objective: We determine tetanus seroprotection rates and physician compliance with tetanus prophylaxis recommendations among patients presenting with wounds.
Methods: A prospective observational study of patients aged 18 years or older who presented to 5 university-affiliated emergency departments (EDs) because of wounds was conducted between March 1999 and August 2000. Serum antitoxin levels were measured by enzyme immunoassay with seroprotection defined as more than 0.15 IU/mL. Seroprotection rates, risk factors for lack of seroprotection, and rates of physician compliance with tetanus prophylaxis recommendations by the Advisory Committee on Immunization Practices were determined.
Results: The seroprotection rate among 1,988 patients was 90.2% (95% confidence interval 88.8% to 91.5%). Groups with significantly lower seroprotection rates were persons aged 70 years or older, 59.5% (risk ratio [RR] 5.2); immigrants from outside North America or Western Europe, 75.3% (RR 3.7); persons with a history of inadequate immunization, 86.3% (RR 2.9); and persons without education beyond grade school, 76.5% (RR 2.5). Despite a history of adequate immunization, 18% of immigrants lacked seroprotection. Overall, 60.9% of patients required tetanus immunization, of whom 57.6% did not receive indicated immunization. Among patients with tetanus-prone wounds, appropriate prophylaxis (ie, tetanus immunoglobulin and toxoid) was provided to none of 504 patients who gave a history of inadequate primary immunization (of whom 15.1% had nonprotective antibody titers) and to 218 (79%) of 276 patients who required only a toxoid booster.
Conclusion: Although seroprotection rates are generally high in the United States, the risk of tetanus persists in the elderly, immigrants, and persons without education beyond grade school. There is substantial underimmunization in the ED (particularly with regard to use of tetanus immunoglobulin), leaving many patients, especially those from high-risk groups, unprotected. Better awareness of tetanus prophylaxis recommendations is necessary, and future tetanus prophylaxis recommendations may be more effective if they are also based on demographic risk factors.