Pregnant women are to be vaccinated against whooping cough, health officials have said, after the biggest outbreak of the illness for two decades claimed the lives of 10 babies.
So far this year 10 infants under the age of three months have died as a result of the infectious disease - including nine in England and one in Northern Ireland.
There have been 4,791 confirmed cases in England and Wales between January and August - four times more than the total figure for 2011, when there were 1,118 cases, said the Health Protection Agency (HPA).
Chief Medical Officer Professor Dame Sally Davies, the Government's principal medical adviser, said that mothers-to-be will be offered the vaccination to protect their newborn babies.
Youngsters cannot receive the jab until they are two months old. Vaccinating their mothers before they are born will boost their immunity until they reach the age they can get the injection themselves, Prof Davies said.
From Monday, women across the UK who are between 28 and 38 weeks pregnant will be offered the vaccination.
Prof Davies said: "Whooping cough is highly contagious and newborns are particularly vulnerable. It's vital that babies are protected from the day they are born - that's why we are offering the vaccine to all pregnant women. This will protect the baby from whooping cough up to the time of the first immunisation at eight weeks."
However, the drug which is to be administered, called Repevax, comes with the recommendation: "Limited post-marketing information is available on the safety of administering Repevax to pregnant women. The use of this combined vaccine is not recommended in pregnancy".
But the Joint Committee on Vaccination and Immunisation - the independent panel of vaccine experts which advises the Government - said that it has "no concerns" about the safety of the vaccine, which protects against whooping cough, diphtheria, tetanus and polio.
Prof Davies added: "I know that pregnant women can feel very vulnerable about protecting themselves and their baby's health and clearly we don't want pregnant women taking medication of any form unless it's necessary. But I can't stress enough that this is an important thing that pregnant women can do to protect their baby."