What is the risk of tetanus infection in the USA if one opts out of receiving the Tdap (Tetanus, diphtheria, and pertussis) booster?

Risk of Tetanus Infection in the USA Without Tdap Booster

Tetanus infection risk in the USA is extremely rare for those who have completed their primary vaccination series, even if they opt out of receiving the Tdap booster. 1

Current Epidemiology of Tetanus in the USA

The incidence of tetanus in the United States has declined dramatically since the introduction of tetanus vaccines. According to CDC data, tetanus cases are now rare in the United States 1:

• Before vaccine availability, tetanus was a common disease with severe morbidity and mortality
• The number of reported cases declined dramatically following universal childhood vaccination
• Cases of tetanus are now rare in the United States due to the routine childhood vaccination program and decennial booster doses

Primary Protection and Booster Recommendations

The Advisory Committee on Immunization Practices (ACIP) provides the following guidance:

• A completed primary tetanus vaccination series generally induces protective levels of serum antitoxin that persist for ≥10 years 1
• For routine protection, adults should receive a tetanus booster (either Td or Tdap) every 10 years after completing their primary series 2
• Either Td or Tdap may be used for booster doses, as both provide adequate protection against tetanus 1

Risk Assessment for Unvaccinated vs. Previously Vaccinated Individuals

The risk of tetanus infection varies significantly based on vaccination history:

• For unvaccinated individuals: Risk is substantially higher
• For individuals with completed primary series but no booster: Risk remains very low
• For wound management: Risk assessment depends on wound type and time since last vaccination:
  • Clean, minor wounds: Booster needed if ≥10 years since last dose
  • Contaminated wounds (dirt, feces, soil, puncture wounds): Booster needed if ≥5 years since last dose 1, 2

Clinical Implications of Skipping the Tdap Booster

If someone opts out of receiving the Tdap booster but has completed their primary vaccination series:

1. Tetanus protection: Likely remains adequate for many years beyond the 10-year mark, though exact duration of protection varies individually
2. Diphtheria protection: Similar to tetanus, protection likely extends beyond 10 years
3. Pertussis protection: This is the component most affected by skipping Tdap, as pertussis antibodies decline rapidly after the first year following vaccination 1

Important Considerations and Caveats

• Wound management: Even if someone opts out of routine boosters, they should still receive a tetanus-containing vaccine for wound management if indicated based on the nature of the wound and time since last vaccination 1, 2
• Special populations: Pregnant women should receive Tdap during each pregnancy regardless of prior vaccination history to protect newborns from pertussis 1, 2
• Healthcare access: Studies have shown that barriers to vaccination include low awareness of Tdap and low perceived risk of contracting diseases, particularly pertussis 3

Bottom Line

The risk of tetanus infection in the USA for someone who has completed their primary vaccination series but opts out of the Tdap booster is extremely low. However, maintaining protection through recommended boosters remains important, particularly for wound management and for protecting vulnerable populations from pertussis.