Whooping cough vaccinations are at the center of a media buzz today, thanks to a study in the New England Journal of Medicine showing that the effect of the current vaccine, called DTaP, fades more quickly than physicians had hoped.
The research, by Nicola Klein, MD, PhD, and colleagues at the Kaiser Permanente Vaccine Study Center, began as an effort to understand why California had such a large whooping cough outbreak in 2010, in spite of the fact that many of the school-aged children who came down with the disease had been fully vaccinated.
The vaccine for whooping cough, which is also called pertussis, is usually given in five doses in early childhood, with the fifth dose before kids begin kindergarten. Although the DTaP (for Diptheria, Tetanus and acellar Pertussis) vaccine does confer immunity, the faster-than-expected waning of that protection potentially leaves many fully-vaccinated 8- to 11-year-olds vulnerable to whooping cough. (Those aged 11 and up are already encouraged to get a DTaP booster.)
Time’s Healthland blog explains the findings:
“We found a substantial waning in protection in the five years after the fifth dose,” says Klein, adding that the findings do not suggest the current vaccine is useless. “We also found was that some protection is better than no protection. The existing DTaP is safe and effective, but protection just doesn’t last as long as we’d like.”
Although the vaccine’s effectiveness weakens over time, the protection it offers is still critical for maintaining enough population-based immunity to safeguard infants, who are too young to be vaccinated against infection. Health experts stress that parents should not to stop vaccinating their kids just because the immunizations appear to lose their effectiveness.
Previously: Failure to vaccinate linked to pertussis deaths, Washington state starts school year with tougher requirements for vaccine exemptions, How to save $83 billion? Vaccinate and Unvaccinated children may pose a public health risk
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