THE controversial measles, mumps and rubella vaccine can sometimes cause a rash-like reaction in children, a study in Britain has confirmed. Although this side effect has been known for over 10 years, the latest work gives a more accurate assessment of the risk.
The rash is the result of a bleeding disorder called idiopathic thrombo-cytopenic purpura, or ITP, which is caused by a shortage of the platelets involved in clotting. This can cause mild bleeding beneath the skin.
Most children make a complete recovery within a couple of weeks. Fewer than 5 per cent of patients develop chronic problems that require treatment.
What's more, the majority of ITP cases are caused by viral infections such as measles, so it's not surprising that the weakened viruses in the MMR vaccine can also trigger it. "The children who develop ITP after vaccination tend to have milder symptoms than those developing it after ...
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