Tetanus, diphtheria, and pertussis are serious bacterial infections that can lead to life-threatening complications. Each disease affects the body in different ways:
- Tetanus (lockjaw) causes painful muscle stiffness and spasms. It can make it hard to breathe or swallow and is often triggered by bacteria entering the body through cuts or wounds
- Diphtheria can lead to breathing problems, heart failure and nerve damage. It spreads through coughing or sneezing
- Pertussis (whooping cough) causes violent coughing fits that can make it hard to breathe. It’s especially dangerous for babies who haven’t been vaccinated yet
Before vaccines were available, these diseases caused thousands of deaths every year in the U.S. For example, the CDC reports that diphtheria used to cause up to 15,000 deaths annually. Thanks to vaccination efforts, cases of diphtheria and tetanus are now extremely rare. However, pertussis outbreaks can still occur, especially among people who haven’t been vaccinated or whose immunity has faded.
Even though these diseases are caused by different bacteria, one vaccine, the Tdap shot, can help protect against all three. Tdap is a booster vaccine for older children and adults. It’s different from the DTaP vaccine, which is given to young children.
How the Tdap vaccine works and who should get it?
The Tdap vaccine helps your body build protection against tetanus, diphtheria and pertussis. It’s recommended for:
- Children age 7 and older who missed earlier DTaP doses
- Preteens at age 11 or 12 as a routine booster
- Pregnant women during each pregnancy (ideally between weeks 27–36) to protect newborns from pertussis
- Adults who never had Tdap, and then a booster every 10 years. Anyone in close contact with infants, including parents, grandparents, and caregivers. The vaccine is safe and well-tolerated. Common side effects include mild pain or swelling at the injection site, fatigue or a low-grade fever. Serious side effects are rare.
Tdap is especially important for protecting infants from pertussis. Babies can’t get their first vaccine dose until they’re 2 months old, so they rely on the immunity of those around them.
How long does Tdap protection last?
Immunity from the Tdap vaccine wanes over time, which means it fades and becomes less effective. Here’s what we know:
- Tetanus and diphtheria protection lasts about 10 years, which is why boosters are recommended every decade
- Pertussis protection also fades and adults can catch whooping cough even if they were vaccinated years ago
You might need a booster if:
- It’s been more than 10 years since your last Tdap or Td shot
- You’re pregnant or planning to become pregnant
- You’re caring for a newborn or working in childcare
- You’re unsure of your vaccination history
If you’ve received a Td booster (which protects only against tetanus and diphtheria), you can safely switch to Tdap for your next booster to add pertussis protection.
Why staying up to date matters?
These diseases are preventable but still present:
- Tetanus bacteria live in soil and can enter the body through cuts or wounds
- Diphtheria is rare in the U.S., but it still occurs in other countries and can be brought back through travel
- Pertussis is highly contagious and spreads quickly in schools, workplaces and homes
Staying up to date with your Tdap vaccine helps protect you and those around you from serious illness. Check your vaccination records and talk to your healthcare provider about getting a booster if it’s not contraindicated for you.
Want to know your immunity status?
If you’re curious about your antibody levels, Labcorp OnDemand offers simple blood tests:
- Tetanus and Diphtheria Antibody Test: Find out if you have antibodies that protect against tetanus and diphtheria
- Pertussis Antibody Test: Check if you have antibodies to whooping cough
