Childhood measles may protect from asthma

Could early infections protect against asthma?

Having measles when very young may slightly decrease the chance of developing asthma later in life, say scientists.

However, other experts have warned that the risks connected with the natural infection are too great to consider not allowing a child to have the MMR vaccination.

There is already some evidence that measles infection reduces the likelihood of developing asthma as a child.

The latest research, however, conducted in Aberdeen, is the first to suggest that these positive effects of measles infection may continue even into the 20s and 30s.

The study looked at more than 300 people, who, as children, had been part of a health survey in 1964.

Their results suggested a slight connection between those who had not been infected with measles as a child, and wheezing conditions which developed in adulthood.

However, other experts pointed out that any protection or otherwise conferred by measles infection was dwarfed by the most significant risk factor for asthma - whether either or both parents were asthmatic themselves.

Genetics important

Dr Rob Niven, a consultant chest physician from the North West Lung Unit at Wythenshawe Hospital in Manchester, said: "The genetic risk is still by far the most important.

"If both of your parents have asthma, then you have a 70% or 80% risk of developing it yourself.

"There is some evidence that early infection with measles virus very slightly reduces the risk of developing asthma.

"But it's important to stress that children should still have the MMR vaccination."

Dr Martyn Partridge, chief medical adviser to the National Asthma Campaign, said that this was simply one of several studies which suggested that early life infections offered some protection against asthma.

"However, the bulk of the other studies suggested that it is development of the bowel immune system which is most important.

"What we now need are intervention studies where we give at-risk children not an illness but some form of controlled infection or vaccine, that can have the same beneficial effect by simulating infections."

Aside from a child's inherited genetic predisposition to asthma, other factors which are thought to influence whether they develop it or not include the number of brothers or sisters they have, and to a certain extent their diet in the early years.

But again, the effect of these factors is tiny compared to genetics.

Natural measles infection, while not harmful to most children, carries a slight risk of permanent disability - or even death.

The latest research was published in the medical journal Thorax.