But experts stressed the vaccine remains highly effective in protecting the most vulnerable young babies. There has been a global resurgence of whooping cough in recent years. In 2012, there were almost 10,000 confirmed cases in England and Wales – a dramatic increase from the last “peak” of 900 cases in 2008.
The outbreak led to 14 deaths in babies under three months of age – the group who are most vulnerable to infection. Rising figures prompted health officials to recommend vaccination of pregnant women so immunity could be passed to their newborns – a strategy that a recent study showed was working well.
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