Abstract and Introduction
Tetanus is an acute and sometimes fatal disease characterized by sudden muscle contractions. The number of tetanus cases reported annually in the United States has declined significantly since the 1930s and 1940s as a result of the introduction of tetanus vaccines. However, sporadic cases continue to occur in persons who are not up-to-date with tetanus toxoid-containing vaccinations (TT) and do not receive appropriate postexposure prophylaxis (PEP). To assess the extent of these cases, the California Department of Public Health reviewed all tetanus cases reported during January 2008–March 2014. A total of 21 tetanus patients were reported; five (24%) died. An average of three cases were reported each year during 2008–2013; the average annual incidence among patients aged ≥65 years (0.23 cases per 1 million population) was twice that among patients aged 21–64 years (0.10 cases per 1 million population). Of 16 patients with an acute injury before illness and diagnosis, nine (56%) sought medical care, and two (22%) of the nine received appropriate PEP. Although tetanus is rare, it is a life-threatening disease that is preventable. Health care providers should ensure that their patients are up-to-date with TT vaccination and provide appropriate postexposure prophylaxis for patients with wounds.
During 2008–2010, a confirmed case was defined by the Council of State and Territorial Epidemiologists (CSTE) as a patient with acute onset of hypertonia or painful muscular contractions (usually of the muscles of the jaw and neck) and generalized muscle spasms without other apparent medical cause.* In 2010, CSTE removed the "confirmed" classification and defined all clinically compatible cases as probable.† The California Department of Public Health analyzed all confirmed and probable cases in accordance with CSTE case definitions. Using the CDC tetanus surveillance worksheet, local health department and California Department of Public Health staff reviewed case surveillance and medical record data, including demographics, clinical presentation and course, vaccination status, and wound management. Vaccination and wound data were reviewed to determine whether health care providers followed wound management and PEP recommendations.[2,3] Tetanus incidence rates were calculated using population estimates from the California Department of Finance. Hospitalization costs were estimated using discharge data from the Office of Statewide Health Planning and Development.
During January 2008–March 2014, a total of 21 tetanus cases were reported; five (24%) were fatal ( Table 1 ). The patients were all adults ranging in age from 21 to 89 years (median = 52 years); 15 (71%) were male. An average of three cases were reported each year during 2008–2013 (range = 0–5). The average annual tetanus incidence rate during 2008–2013 was 0.09 cases per 1 million population, compared with 0.19 cases during 2002–2007. During 2008–2013, the average annual incidence among patients aged ≥65 years (0.23 cases per 1 million population) was twice that among patients aged 21–64 years (0.10 cases per 1 million population). The case-fatality rate among patients aged ≥65 years was 50%, compared with 13% among patients aged 21–64 years. Race and ethnicity were reported for 18 (86%) patients. The average annual incidence rates among Hispanics (0.08 cases per 1 million population), non-Hispanic whites (0.09), non-Hispanic blacks (0.07), and non-Hispanic Asians/Pacific Islanders (0.03) were similar.
All 21 tetanus patients were hospitalized; 19 (90%) were admitted to an intensive care unit, and nine required mechanical ventilation. The median number of days hospitalized was 18 (range = 2–65); of 15 patients for whom data were available, the median cost of total hospital charges per patient was $166,259 (range = $22,229–$1,024,672). Seven patients had conditions associated with increased risk for tetanus; four were diabetic, and three were injection-drug users. TT history was reported for 12 (57%) patients; three (25%) could not recall receiving any doses, and nine (75%) recalled receiving ≥1 dose. Among the nine patients who recalled receiving ≥1 dose, six received their last dose 10 to 50 years before their illness, and three could not recall when they received their last dose.
Sixteen (76%) patients reported that an acute injury had occurred before illness onset; including punctures (seven), abrasions (four), linear lacerations (three), compound fracture (one) and animal bite (one). Of six patients with data on wound depth, two had wounds that were >1 cm deep. Seven of 11 patients with available data had wounds that appeared infected, and two of seven patients with available data had wounds with devitalized, ischemic, or denervated tissue. Five patients reported no acute injuries before onset; of these, three were injection-drug users. The remaining two patients could not recall any acute injuries; however, one reported an insect bite, and the other reported chronic abrasions on the hands and feet and exposure to soil.
Of the 16 patients who reported acute injuries before illness onset, nine had sought medical care for their injuries ( Table 2 ). Of the nine, only two received appropriate PEP before the onset of tetanus symptoms as recommended by the Advisory Committee on Immunization Practices (ACIP) ( Table 3 ).[2,3] Of the seven patients who did not receive appropriate PEP, five had punctures or contaminated wounds and unknown TT vaccination histories, and should have received both TT and tetanus immune globulin (TIG) as recommended. However, four patients did not receive any PEP, and one received TT PEP only. Of the two remaining patients, one had a clean, minor wound and reported receiving at least one TT dose more than 10 years ago, but was not offered TT PEP as recommended; the other patient was contraindicated for TT because of a history of anaphylaxis, but was not offered TIG as an alternative.
Following their tetanus diagnoses, all 21 patients were treated with TIG; six were treated ≤1 day after symptom onset, eight ≤4 days, six ≤9 days, and one was treated >2 weeks after onset. Among the five fatal cases, one patient was treated ≤1 day after symptom onset, two were treated ≤4 days, and two ≤9 days after onset. Of 15 patients for whom data on TIG dosage were available, five received less than the 3,000–6,000 U that is generally recommended for treatment; two received less than 500 U, and three received 500–1,000 U.
*Additional information available at https://wwwn.cdc.gov/NNDSS/script/casedef.aspx?CondYrID=864&DatePub=1/1/1996.
†Additional information available at https://wwwn.cdc.gov/NNDSS/script/casedef.aspx?CondYrID=865&DatePub=1/1/2010.
Morbidity and Mortality Weekly Report. 2015;64(9):243-246. © 2015 Centers for Disease Control and Prevention (CDC)