The latest figure on the number of measles cases in Wales is due out later. There are currently over 1,000 confirmed cases of measles following the outbreak centred around Swansea.
2013 is expected to be the worst year for measles in the UK for the past two decades. Read more about the illness and how it is treated.
If the Government's top adviser on immunisation thinks the risk of an emergency in England is a possibility, I believe him.