How viral infections lead to asthma

London, September 10 (ANI): Study on mice has found that viral infections in newborns "cripple" part of the immune system and increase the risk of asthma later in life.

US researchers behind the study hope their findings, published in the journal Nature Medicine, will help develop ways of preventing asthma.

Earlier studies have shown a link between repeated lung infections with respiratory syncytial virus (RSV) and developing asthma later in life.

However, how the virus might lead to an increased risk of asthma has remained unknown.

Now a team of researchers at the University of Pittsburgh School of Medicine believe they have an explanation.

Their experiments on mice showed the virus impaired the ability of a specific part of the immune system, called regulatory T cells, to calm inflammation.

The tightened airway of an asthma patient and a healthy airway

Inflammation is an important part of dealing with an infection. However, for asthma patients, chemicals in air which come from ordinary things like dust mites, pets and mould can trigger an inappropriate inflammatory response.

Infection with RSV led to a "complete loss of suppressive function" of the regulatory T cells, after which the mice developed asthma-like symptoms," researchers Prof Anuradha Ray and Prof Prabir Ray told the BBC.

They think the finding could help scientists devise treatments, which prevent some people developing asthma. (ANI)