Tdap is a combination vaccine that protects against three potentially life-threatening bacterial diseases: tetanus, diphtheria, and pertussis (whooping cough). Td is a booster vaccine for tetanus and diphtheria. It does not protect against pertussis.
Tetanus enters the body through a wound or cut. It affects the brain and nervous system and causes extremely painful muscle spasms. Spasms of the jaw can make it impossible for you to open your mouth. This condition is often called "lockjaw." Tetanus kills one out of five people infected with the disease.
Pertussis, or whooping cough, is an extremely contagious respiratory infection that can lead to severe breathing problems, especially in infants. Pertussis first appears like an ordinary cold, but then causes intense, uncontrollable coughing spells. A "whoop" noise is heard when the person tries to take a breath after coughing.
These diseases were once quite common in the U.S. and led to many deaths. However, routine vaccinations have helped nearly eliminate tetanus and diphtheria infections. Pertussis is the only vaccine-preventable disease that continues to rise in the U.S. Before 2005, only young children could receive the pertussis vaccine. Waning immunity and inadequate vaccination -- many parents choose not to vaccinate their children -- have led to a resurgence of the disease in the U.S. in recent years. Outbreaks of pertussis among adolescents and adults have been reported in several states.
Tdap vaccination offers the best prevention against pertussis, tetanus, and diphtheria. Tdap stands for tetanus and diphtheria toxoids with acellular pertussis. It is marketed under the brand names Adacel and Boostrix.
Tdap is an inactive vaccine, which means it is made using dead bacteria. The dead germs cannot make you sick. Tdap is not the same as DTaP, the vaccine used for children to prevent the same diseases.
When Should Adults Be Vaccinated With Tdap?
The CDC recommends the Tdap vaccine for all adults ages 19 and older who have never received the vaccine, especially:
- Health care workers who have direct contact with patients
- Caregivers of infants under 1 year old, including parents, grandparents, and babysitters
- Pregnant women in their third trimester (ideally 27th through 36th week), even if they have previously received Tdap vaccine; this can protect a newborn from whooping cough in the first months of life.
- New mothers who have never received the Tdap
- People who travel to countries where pertussis is common
You may be given the Tdap vaccine if you have a severe cut or burn and have never received a dose before. Severe cuts or burns raise your risk for tetanus.
The Tdap vaccine can be given any time of the year. Only one shot is needed. It may be given with other vaccinations. Tdap can be given regardless of the interval since the last Td vaccine was given.
The Tdap vaccine can be used safely for those ages 65 and over, according to 2013 CDC recommendations.
Who Needs a Booster Shot?
Tdap is given only once during your lifetime. However, you may need routine booster shots of the Td vaccine every 10 years to adequately protect you against tetanus and diphtheria.
Who Should Not Get the Vaccine?
You should not receive the vaccine if you have had:
- A serious allergic reaction to any of the vaccine ingredients in the past
- A coma or seizures within a week of receiving childhood vaccinations for pertussis (such as DTaP), unless the vaccine was not the cause; Td can be used in these cases.
If you have had any of the following, talk to your doctor about whether the Tdap or Td vaccine is right for you:
- Epilepsy or another nervous system problem
- Guillain-Barré syndrome (GBS)
- A history of severe swelling or pain after receiving a pertussis, tetanus, or diphtheria vaccination in the past
- If you are moderately to severely ill (your doctor may recommend waiting to get the shot until after you recover); the CDC says you can still get the vaccine if you have a mild illness such as a cold or low-grade fever.
What Are the Side Effects and Risks of Tdap and Td?
Like all medicines, vaccines can have side effects. However, the chance of a life-threatening reaction is small. The CDC says the dangers of developing pertussis, tetanus, or diphtheria far outweigh the risks of vaccination.
Mild side effects of Tdap may include:
Mild side effects of Td may include:
- Pain, redness, or swelling in the arm where the shot was given
- Mild fever
In some people, these side effects may be more intense. They may temporarily interfere with daily activities. Severe swelling of the arm has been reported in three out of 100 people receiving either Tdap or Td. About one in 250 adults who receive the Tdap vaccine develop a fever of 102 F or higher.
During clinical trials of Tdap, two adults developed temporary nervous system problems. It's unknown whether this was due to the vaccine or not. In rare cases, vaccination with Tdap or Td has led to extreme swelling of the arm where the shot was given.
Can Adults Have Allergic Reactions to Tdap or Td Vaccines?
Although it's rare, someone may have a severe allergic reaction to an ingredient in the Tdap or Td vaccine. This generally happens in less than one in a million doses. Most of the time, such reactions occur within a few minutes of receiving the vaccine. The following can be signs of a severe allergic reaction, called anaphylaxis:
- Behavior changes
- Breathing difficulty, including wheezing
- Hoarse voice
- High fever
- Pale skin
- Rapid heart beat
Seek immediate medical care if you notice any of these signs after receiving the Tdap or Td vaccines.