Professor David Salisbury, director of immunisation at the Department of Health, said:
Whooping cough is highly contagious and infants are particularly vulnerable. Thirteen infants have died as a result of whooping cough this year and there have been nearly 400 cases of the disease in children under three months old. It's vital that babies are protected from the day they are born - that's why we are encouraging all pregnant women to be vaccinated.
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