Whooping Cough Vaccine Protection Might Wane Sooner Than Previously Thought

Posted by L. Shaka on September 22, 2011 Add comments

Sep 222011

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According to new research by Dr. David Witt, presented at the American Society for Microbiology conference in Chicago on Monday, the protection conferred by the whooping cough vaccine, as currently administered might wane quicker than previously thought. His study suggests that the vaccine’s protection might considerably wane as soon as 3 years after receipt of the last dose.

The study looked at 15,000 children in Marin County, California, including 132 who got whooping cough last year. It found that children who had gone three years or more since the last of their five original shots were up to 20 times more likely to become infected than children who had been more recently vaccinated. The biggest number of cases was in children 8 to 12 years old. The CDC’s own studies also show a drop off in protection, however not as steep as Dr. Witt’s drop.

So what does all this mean? Given that this study is relatively small, even its authors agree that it needs further confirmation. If the results hold however, it might mean that the time between booster shots may need to be reduced. Alternatively, a more effective vaccine might be developed, although I cannot say how realistic that scenario might be. Or it may not lead to any changes. Although protection wanes, generally speaking vaccinated children have less severe cases of illness than unvaccinated kids, so the waning protection might not justify a change in the booster shot timing or frequency. It is simply too early to say at this point.

One thing this study does not say however is that whooping cough vaccines are inefective. As a matter of fact, Dr. Witt found that the vaccine was extremely effective and that rates of whooping cough dropped dramatically after kids were age 11 and 12, when many get the booster shot.