Viral infections in the neonatal period adversely affect the immune system, which increases the risk of asthma later in life, according to the journal Nature Medicine.
Asthma is a chronic, inflammatory disease of the airways. When a patient’s airways become irritated, the muscles in their wall contract and the production of sticky mucus increases. This makes breathing difficult.
Earlier studies have suggested an association between recurrent respiratory infections with RSV and the emergence of asthma later in life.
For example, a Swedish study showed that 39 percent. of infants admitted to hospital with RSV infection had asthma at the age of 18, while only 9% of children who did not have such an infection in infancy developed asthma.
However, it was not known how the virus would cause asthma. Researchers at the University of Pittsburgh School of Medicine say they were able to explain this phenomenon by studying mice.
They showed that infections caused by RSV deprive cells of the immune system (regulatory T lymphocytes) of their ability to soothe inflammation in the airways.
The authors of the study say that the results obtained will help in the development of methods of preventing and treating the disease. Early in life, they say, is a window – a time when immune cells are especially vulnerable. (PAP)
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