People with asthma are likely to have worse symptoms when they get the flu because they have weaker immune systems, a new research has shown.  

The study, led by Dr Ben Nicholas from University of Southampton, assessed lung samples from asthmatics and healthy volunteers. The samples were exposed to influenza and their reactions were analysed.

This study was published in the Journal of Allergy and Clinical Immunology. Dr Nicholas said, “We wanted to look into whether immune system differences explain why asthmatics are more likely to end up in hospital if they get flu than the general population. This is important, as flu can cause a person’s asthma symptoms to get worse. The samples from healthy people showed a strong immune system-triggering reaction to the flu virus. But in lung samples from asthma patients, this reaction was much weaker.”

“We hope these results help researchers better understand why asthmatics are more affected by influenza and help find new treatments for common lung infections, which often make asthma symptoms worse,” he added.

The research method Dr Nicholas used is different other techniques, which separate and grow a single layer of cells in a dish. Instead, Dr Nicholas kept the whole sample intact, which allowed him to study a pin-head sized piece of lung in the lab, as it would be found in the body.

The study was supported by, and conducted in collaboration with Synairgen, a University of Southampton spin-out company, and formed part of U-BIOPRED, a large-scale European project using information and samples from adults and children to learn more about different types of asthma. More research is now needed to investigate whether the difference in immune responses is due to the asthma itself, or the daily medications used by participating asthmatics to control their condition.