Whooping cough immunity may wane after vaccination: study

(Reuters Health) - Unvaccinated youngsters were nine times more likely to contract whooping cough during a recent outbreak in California than those who had received the entire five-shot series, researchers found. However, the effectiveness of the ...

Source: http://health.yahoo.net/news/s/nm/whooping-cough-immunity-may-wane-after-vaccination-study

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