HEALTH / Common Complaints: Measles

IN THE 1960s I worked briefly in a fever hospital; I still remember a ward full of silent children, lying unconscious or semiconscious from the effect of measles on the brain - measles encephalitis. Then, and today, this rare complication of measles affects perhaps one in a thousand children with the illness. At best the child is feverish, drowsy and confused for a week; at worst, he or she suffers permanent brain damage leading to epilepsy or mental handicap. About 10 per cent of children with measles encephalitis die.

Even uncomplicated measles is an unpleasant illness. At first the child seems to have a feverish cold, with sore eyes, a runny nose and a cough. After three or four days, small red spots appear on the face and the rash soon spreads to the rest of the body. The rash fades after another three to four days, and the child should then recover - but often the convalescence is prolonged by earache or a chest infection. Children who are undernourished or in poor health may become very ill with measles: in Africa and Asia it still kills hundreds of thousands of children every year, and an African proverb tells mothers not to count the number of children they have until all have had measles.

For centuries virtually all children caught measles before the age of 10, but a single attack usually gave lifelong immunity. A vaccine became available in the 1970s, but publicity about the alleged dangers of other vaccines had dented public confidence in all immunisation; in Britain, as recently as the mid-1980s, around 100,000 children a year contracted measles. The introduction in 1988 of a new triple vaccine against measles, mumps and rubella (MMR) was accompanied by effective publicity which led to a return of public confidence in the safety of vaccines. It now looks as if immunisation should make the disease more or less extinct by the end of the century - at least in those Western countries that can afford to supply the vaccine to all their children.

The World Health Organisation is making good progress with its campaign to bring the vaccine to children everywhere, but it will be an expensive undertaking. There are a few question marks; in the United States small outbreaks of measles in teenagers have suggested that a single shot of the vaccine may not give full immunity, and the authorities there now recommend a second dose when a child starts school. Only time will tell whether the disease can be wiped out, but without doubt it will become rare.

If and when the epitaph comes to be written for measles, its place in history should not be forgotten. It was unknown to the ancient Greeks - Hippocrates, who described the diseases of his time with precision, had clearly never seen it. Historians believe it arrived in Europe from central Asia around AD 250, and was probably the 'pestilence' that struck the Roman empire at that time - causing as many as 5,000 deaths a day in Rome at the height of the outbreak and contributing to the decline of the empire. Its devastating impact was due to the high mortality rate that infections have in communities for which they are new diseases. Measles killed millions of people when it came to central America in the 16th century and in the Pacific it wiped out some isolated peoples completely. The Aids virus, HIV, is just the latest new infection to have a devastating effect on the first generation it attacks.