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Pertussis, also known as whooping cough, is a serious illness. It’s highly contagious, can leave you with a hacking cough for months, and is especially dangerous to babies. The CDC reports that cases are on the rise this year. Fortunately, most of us have already been vaccinated against pertussis—but that immunity fades over time. You may need another dose.
What is pertussis?
Pertussis, or whooping cough, is caused by a species of bacteria called Bordetella pertussis. The bacteria attach to the inside surface of the lungs and release a toxin that causes tissues to swell. Its characteristic symptom is a persistent, severe cough.
Pertussis has been nicknamed the “100-day cough” because its symptoms can last that long. “Whooping cough” is named after the sound you might make when gasping for air during a coughing fit. Vomiting, exhaustion, and trouble breathing may accompany the coughing fits; it’s not unheard of to break a rib coughing. For babies, the coughing can interfere with breathing enough to be life threatening.
The symptoms of pertussis may initially appear the same as for a common cold, with the coughing fits developing over time. It’s also possible for a person who is lucky and has a strong immune system to carry and pass on the bacteria without any noticeable symptoms. That’s why the vaccine is so important—you can spread pertussis before you feel sick, or even without realizing you are sick.
Immunity from the vaccine fades over time
There is a pertussis vaccine, and it’s routinely given in childhood, with the major caveat that babies need to be 2 months old before they can get it.
There are actually two vaccines: DTaP is given to young children, and it protects against three diseases: diphtheria (the D in the acronym), tetanus (T), and pertussis (aP, for acellular pertussis). There used to be a whole-cell pertussis vaccine, which is no longer used. Older children and adults get a similar vaccine, called Tdap, which protects against the same illnesses but contains smaller doses of the diphtheria and pertussis components. If you’re old enough to read this article, Tdap is the one you’ll get.
Most of us had several doses of pertussis vaccine as children, and if that’s the case, we were protected for years. But the CDC notes that pertussis immunity fades over time. So far, there is no official recommendation for whether or how often to get a booster shot. But a TDaP shot, which immunizes you against tetanus, diptheria, and pertussis, can be given as your every-10-years tetanus protection. Make sure to ask for TDaP specifically, because sometimes a “tetanus shot” only includes tetanus and diphtheria protection.
Who needs a pertussis vaccine, according to the CDC
The official recommendations, according to the CDC, are for the following people to get a pertussis shot:
Young children need a five-dose DTaP series starting at 2 months of age; the last shot of the series is usually given when they are 4 to 6 years old.
Older children need a single shot of Tdap at age 11 or 12.
Adults who never got a Tdap shot should get a Tdap shot. This can happen anytime. How about now?
Anyone who is pregnant should get a Tdap shot during the third trimester of each pregnancy. This gives the baby some antibodies against pertussis that can protect them during those early months of life when they are too young to get the pertussis vaccine themselves.
Adults who spend time around babies—such as grandparents and babysitters—aren’t specifically recommended to get a Tdap booster, but many healthcare providers would say that it’s still a good idea. It’s usually fine to get a Tdap shot even if you’ve had one a few years ago, or aren’t sure whether you’ve had one. As always, check with your healthcare provider if you have questions or want to be sure that it’s right for you.