Tetanus, diphtheria, and pertussis are very serious diseases. Tdap vaccine can protect us from these diseases. And, Tdap vaccine given to pregnant women can protect newborn babies against pertussis.
Long considered a conquered childhood disease, pertussis has made a comeback in the U.S., in part because the combination vaccine, DTap, appears less effective than its predecessor, DTP
Some (Australia, Canada, Ireland, Spain, UK, US), not all, countries that switched from whole cell (wP) to acellular (aP) pertussis vaccines saw in subsequent decades...Protection that turned out to be both weaker and of shorter duration in adolescents. Resurgence of pertussis infections, even among those previously vaccinated, i.e., poor herd immunity.
Both vaccines contain inactivated forms of the toxin produced by the bacteria that cause the three diseases. Inactivated means the substance no longer produces disease, but does trigger the body to create antibodies that give it immunity against the toxins. DTaP is approved for children under age 7. Tdap, which has a reduced dose of the diphtheria and pertussis vaccines, is approved for adolescents starting at age 11 and adults ages 19 to 64. It is often called a booster dose because it boosts the immunity that wanes from vaccines given at ages 4 to 6.
Like many other grown-ups, I hadn’t given any thought to what we used to call the D.P.T. vaccine — for diphtheria, pertussis and tetanus — for decades. I got the shots when I was a child, and I made sure my daughter got them during her childhood immunizations. Every now and then, my doctor tells me it’s time for a tetanus booster, so I get one. That’s enough, right?
It’s not news that we need a better pertussis vaccine. Scientists have known for several years that protection against whooping cough wanes much faster than expected in children and adolescents.
Adults have their own vaccination needs, but they’ve often been neglected. Now doctors are trying to correct that.
It’s an ongoing and vexing public health problem: People once vigilant about vaccinating their children aren’t nearly as careful about protecting themselves as they age, even though diseases like influenza, pneumonia and shingles (a.k.a. herpes zoster) are particularly dangerous for older people.
Zika does carry potential dangers for expectant mothers and their babies. But the virus is tame compared to its local counterparts — dengue is nicknamed “break-bone fever,” chikungunya “bending-up fever.” But it is really tame compared to tetanus, diphtheria, and pertussis, the bacterial infections against which Tdap protects.
Whooping cough, a potentially life-threatening childhood illness, all but disappeared in the 1940s after a vaccine was developed. Why is it making a comeback now, when most children are vaccinated?
Rarely, it led to seizures or similar episodes, and even more rarely it caused acute encephalopathy, a more serious but temporary effect on the brain.
Because of all this, we changed the vaccine to the “acellular” kind, which has fewer side effects. We went from DTP to DTaP. And when we did, we stopped protecting children as well as before.