How Long Is Diphtheria Vaccine Effective?
How Long Is Diphtheria Vaccine Effective? Studies estimate that diphtheria toxoid-containing vaccines protect nearly all people (95 in 100) for approximately 10 years. Protection decreases over time, so adults need to get a Td or Tdap booster shot every 10 years to stay protected. Does diphtheria vaccine give lifelong immunity? Previous studies have indicated that