Tetanus surveillance--United States, 1995-1997.

UNLABELLED

PROBLEM/CONDITIONS: Despite widespread availability of a safe and effective vaccine against tetanus, 124 cases of the disease were reported during 1995-1997. Only 13% of patients reported having received a primary series of tetanus toxoid (TT) before disease onset. Of patients with known illness outcome, the case-fatality ratio was 11%.

REPORTING PERIOD COVERED

1995-1997.

DESCRIPTION OF SYSTEM

Physician-diagnosed cases of tetanus are reported by state and local health departments to CDC's National Notifiable Diseases Surveillance System. In addition, since 1965, supplemental clinical and epidemiologic information for cases has been provided to CDC's National Immunization Program.

RESULTS

From 1995 through 1997, a total of 124 cases of tetanus were reported from 33 states and the District of Columbia, accounting for an average annual incidence of 0.15 cases per 1,000,000 population. Sixty percent of patients were aged 20-59 years; 35% were aged > or =60 years; and 5% were aged <20 years, including one case of neonatal tetanus. For adults aged > or =60 years, the increased risk for tetanus was nearly sevenfold that for persons aged 5-19 years and twofold that for persons aged 20-59 years. The case-fatality ratio varied from 2.3% for persons aged 20-39 years to 16% for persons aged 40-59 years and to 18% for persons aged > or =60 years. Only 13% of patients reported having received a primary series of TT before disease onset. Previous vaccination status was directly related to severity of disease, with the case-fatality ratio ranging from 6% for patients who had received one to two doses to 15% for patients who were unvaccinated. No deaths occurred among the 16 patients who previously had received three or more doses. Tetanus occurred following an acute injury in 77% of patients, but only 41% sought medical care for their injury. All patients who sought care were eligible for TT as part of wound prophylaxis, but only 39% received it. Tetanus in injecting-drug users (IDUs) with no known acute injury comprised 11% of all cases, compared with 3.6% during 1991-1994. None of the IDU-associated tetanus cases occurred among persons who were known to have been vaccinated. Sixty-nine percent of IDU-associated tetanus cases were reported from California, and 77% of these cases occurred in heroin users.

INTERPRETATION

Tetanus remains a severe disease that primarily affects unvaccinated or inadequately vaccinated persons. Adults aged > or =60 years continue to be at highest risk for tetanus and for severe disease. However, the overall incidence of tetanus has decreased slightly since the late 1980s and early 1990s, from 0.20 to 0.15, a result primarily of a decreased incidence among persons aged > or =60 and <20 years.

ACTIONS TAKEN

Tetanus is preventable through both routine vaccination and appropriate wound management. In addition to decennial booster doses of diphtheria and tetanus toxoids during adult life, the Advisory Committee on Immunization Practices (ACIP) recommends vaccination visits for adolescents at age 11-12 years and for adults at age 50 years to enable health-care providers to review vaccination histories and administer any needed vaccine. Every contact with the health-care system, particularly among older adults and IDUs, should be used to review and update vaccination status as needed.