How the farmyard bugs that help children avoid asthma could be turned into vaccine

Vaccine: Farmyard bugs could prevent children developing asthma

Farmyard bugs could help develop a vaccine for asthma, according to a study.

Scientists believe the discovery could prevent 1.1million children in the UK from getting the condition.

Researchers have identified several types of "dirty" bacteria and fungi that seem to reduce the chances of developing asthma.

The micro-organisms are linked to known lower rates of asthma among children who grow up on farms.

The evidence provides strong support for the 'hygiene hypothesis' which suggests children's immune systems are not primed properly if they live in conditions which are too clean.

Knowing which bugs might prime the immune system against asthma raises the possibility of developing preventive treatments.

Study leader Dr Markus Ege, from the University of Munich in Germany. said: 'We have a long way to go before we can present new preventive measures, but at least we now have candidates for the development of a vaccine.'

The research is being published in the New England Journal of Medicine.

A number of studies have shown that farm children have a significantly reduced risk of developing asthma.

Dr Ege's team focused on a group of Bavarian schoolchildren, comparing those living on farms with others from the same rural districts who did not.

They found that farm children had to cope with a far wider range of microbes than children living outside farms.

Children exposed to the greatest diversity of bacteria and fungi had the lowest rates of asthma.

Dr Ege added: 'One possibility is that a particular combination of microbial species stimulates the innate immune system and so prevents it from entering a state that promotes the development of asthma.'