Trends in Tetanus Epidemiology in the United States, Pamela Srivastava MS Bacterial Vaccine-Preventable Disease Branch, National Immunization Program Centers for Disease Control and Prevention March 2005
Tetanus Pathogenesis Caused by neurotoxin produced by Clostridium tetani in anaerobic wounds Tetanus spores are ubiquitous –soil –animal or human intestine/feces –skin surfaces –contaminated substances, including heroin
Tetanus Clinical Presentation Characterized by - muscle rigidity - painful muscle spasms 3 types of tetanus (generalized, localized, cephalic) Usually requires hospitalization, ICU care
Tetanus Routine Vaccination/Immunity A primary, 3-dose series + 1 booster provides immunity lasting approximately 10 years Immunity following subsequent boosters lasts years or more Even incomplete immunization reduces disease severity and mortality
Passive reporting system State health departments report weekly to the National Notifiable Diseases Surveillance System Clinical diagnosis - no diagnostic laboratory tests Approx 19% of hospitalized tetanus cases are reported to CDC* Tetanus Surveillance *Estimate based on data from the Healthcare Cost and Utilization Project (HCUP)
Tetanus in the United States: * CFR 91% 4.1/million 2004: 32 cases = 0.11 / million CFR 13% *2004 data not finalized
Tetanus Epidemiology, 30 years ( ) 1837 cases reported: 32 neonatal cases <1 month ∙ 7 deaths (CFR = 21.9%) 1805 cases ≥ 1 year deaths (CFR = 28.4%) - 88% generalized, 12% localized, <1% cephalic
Neonatal Tetanus, % were Hispanic, 34% were white 44% of mothers were unvaccinated, 44% of mothers received 1 dose
Tetanus– Reported Cases and Annual Incidence, CFR 38% CFR 25% CFR 17%
Average annual incidence (per million) Tetanus Incidence by State & > 0.4
Tetanus Incidence, by Region, The South had the sharpest decline in incidence, from 0.52 (1972 to 1981) to 0.17 (1992 to 2001)
Tetanus Cases, by Season,
Tetanus Incidence, by Gender, Overall: Male 51%, Female 48%
Tetanus Vaccination Status, Vaccination History Reported Cases Reported Fatalities Unknown39% (712)38% (273) Not vaccinated34% (611)28% (173) Vaccinated, < 3 doses 21% (369)17% (62) 3+ doses 6% (113) 4% (4)
Tetanus Cases and Deaths, by Age Group, y20-39 y40-59 y60+ y
Tetanus Annual Incidence by Age Group per million
Tetanus Cases and IDUs, by Age Group, y20-39 y40-59 y60+ y
Racial & Ethnic Distribution of Tetanus Cases: IDUs vs. Non-IDUs, Hispanics make up 48% of tetanus cases in IDUs, compared to only 8.4% of cases in non-IDUs
Tetanus Incidence, by Race/Ethnicity, % IDUs
Tetanus in 20 to 39 year olds Incidence rates have not decreased in the yr age group The outbreak of tetanus among IDUs on the West Coast does not account for this lack of decrease When the IDUs are excluded, the proportion of Hispanics is the same as in other age groups
Tetanus among Diabetics % (85/675) of all cases 29% (37/128) of all deaths CFR: 44% mortality (37/85) among diabetics
Diabetes Tetanus Risk*, Overall incidence: diabetics 0.7 /million non-diabetics 0.2 /million Age-adjusted relative risk for tetanus diabetics vs. non-diabetics 3.16 ( ) Age-adjusted relative risk for tetanus death diabetics vs. non-diabetics 4.41 ( ) *Based on population estimates from the US Census and the NCHS Division of Diabetes Translation
Acute Wounds, % (1366/1805) acute wounds –38% punctures (nails & other sharp tools, splinters, body piercing & tattoos) –42% lacerations or abrasions –20% other (blunt trauma, crush injuries, burns, frostbite, surgeries, gunshots, animal bites/scratches)
Non-Acute Wounds, % (285/1805) non-acute wounds –34% chronic ulcers –21% gangrene –21% abscesses / cellulitis –4% dental infections –5% other infections –15% injection drug use (IDU) only 8% (154/1805) of all cases had no identifiable injury/lesion
Impact of Tetanus Severe - CFR 28% - 78% (518/668) hospitalized Expensive* - Average cost per hospitalization: $84,277 (range $ $925,315) - Total annual cost = $12,641,550 *Estimates based on HCUP data,
Summary Tetanus morbidity and mortality have decreased over the past 30 years The elderly and diabetics are at increased risk for disease and death Many cases did not have classic “tetanus prone” wounds
Summary Tetanus disease/mortality associated with inadequate vaccination Racial/regional differences have disappeared Neonatal tetanus virtually non- existent
Recommendations Public Health: –Collect more complete case data (especially vaccination history) Clinicians: –Ensure all patients, especially diabetics, are up-to-date (pay attention to primary series) –Recognize that tetanus can occur even in absence of “tetanus-prone” wounds –Report cases
Acknowledgments State and Local Health Departments Tetanus Team, National Immunization Program, CDC Kristin Brown Jufu Chen Katrina Kretsinger Martha Roper National Immunization Program, CDC Rongping Zhang
Tetanus is Preventable
Regions
Age-Specific Prevalence of Immunity by Sex NHANES III McQuillan et al. Ann Intern Med, May 2002; 136:
Age-Specific Prevalence of Immunity NHANES III McQuillan et al. Ann Intern Med, May 2002; 136:
*McQuillan et al. Ann Intern Med, May 2002; 136: Age-Specific Prevalence of Immunity by Sex * & Reported Tetanus Cases
Tetanus in the Elderly (>60 years), /1805 (52%) of cases were >60 y 379/512 (74%) of total deaths ; CFR: 379/940 (40%) of cases ≥60 y died 379/940 (40%) with no dose, 10/940 (1%) with >3 doses, 405/940 (43%) with missing dose
Tetanus Incidence by Age Group,
Tetanus Cases in Injection Drug Users, Age Groups:
Racial & Ethnic Distribution of Tetanus Cases: Diabetics vs. Non-Diabetics, Among the diabetic cases: 22% were African American and 21% were Hispanic compared to 12% and 16% respectively, among the non-diabetics
Tetanus - Seasonal Trends,
Tetanus in Diabetics, % of diabetics had acute wounds, compared to 76% of non-diabetics Of the 18 diabetics with non-acute wounds, 44% (8) had ulcers and 39% (7) had gangrene—of the non-diabetics with non-acute wounds, 33% had ulcers and 20% had gangrene 68% (44/65) diabetics insulin dependent