Dr Fred Kavalier: Most doctors under 45 have never seen a case of measles – until now

GPs' surgeries are full of young children with rashes and fevers. Sometimes the parent who brings the child to the surgery begins the consultation by saying: "I think he/she might have measles." But for the past 20 years or so in the UK, the parent has almost always been wrong. The truth is that most GPs under the age of 45 have probably never seen a child with measles – until this year.

There are quite a few infections and drug reactions that cause rashes that look a bit like measles. German measles (rubella) and scarlet fever (a rash linked to a throat infection), both look similar to measles. Reactions to antibiotics can cause a measles-like rash. There are at least a dozen other infections, from syphilis to parvovirus B19, that can mimic the measles rash.

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But the distinguishing feature of real measles is that the child is usually really, really ill. In addition to the rash, measles causes a persistent high fever, red watery eyes and a dry cough. Children sometimes complain of sensitivity to the light, which (as all caring parents know) is also a symptom of meningitis.

In my first 20 years as a GP in inner-city London, the only time I saw children with measles was during a sabbatical break when I was working at a hospital in rural Uganda. In the developing world, where nutrition can be poor and medical care is often rudimentary, measles is a major killer of young children.

In the past year, measles has reappeared in the UK. Less than a month ago a mother brought two children to see me on a Sunday. Both had high temperatures, florid red rashes, very snotty noses, watery red eyes. Compared to the average toddler with a few red blotches and a mild temperature, these children were pretty ill. As they entered the consulting room, my first impression was that they probably did have measles.

My suspicion was confirmed when their mother told me that the children were at a school where there has been a confirmed outbreak of measles. One of the children had had only a single dose of MMR (measles, mumps and rubella) vaccine, and the other had not had MMR at all.

The news that measles is making a comeback simply confirms what public health doctors have been warning us about for quite a few years. As MMR immunisation rates have fallen, the population of the UK has begun to lose its "herd immunity". A single case of measles in a school can spread like a prairie fire. Most British children are reasonably well nourished and have easy access to good quality medical care. So we are unlikely to see many children who are killed or permanently damaged by measles. But the suffering that measles causes to otherwise healthy children is bad enough. And the sadness is that all this could have been prevented if the nation hadn't been seized by anti-MMR hysteria.