Researchers at the University of Queensland (UQ) have found that people with a subtype of asthma are extremely vulnerable to influenza, which could result in dangerous flu mutations.
In animal studies, the researchers found that a non-allergic form of the condition, called paucigranulocytic asthma (PGA), allows the flu virus to flourish in greater numbers in sufferers, according to Science Daily.
Katina Hulme of UQ said this was due to asthma’s suppression of the immune system.
She said, “We were first tipped off about this during the 2009 swine flu pandemic. Asthma was identified as the most common underlying medical condition in individuals hospitalized with flu, and these individuals were at a greater risk of ICU admission.”
“Our lab studies have found that non-allergic asthma, or PGA, can suppress the immune response to flu and with the immune system compromised, the virus is left unchecked and can replicate more than it does in a healthy individual,” Hulme added. “And, since the flu is not so good at proof-reading its genetic code when replicating, it makes a lot of mistakes, and with more replication comes more opportunity for mutations to emerge.”
Dr. Kirsty Short of UQ said while the research was preliminary and conducted in animals, the results may reflect a broader phenomenon in humans.
She said, “Our study produced clear findings that fit well with what we know about a suppressed immune response and the emergence of influenza virus variants, which is particularly relevant in the context of COVID-19, where it has been suggested that the so-called UK variant arose because of a prolonged infection in an immunocompromised patient.”
“For this study, it would be interesting to get access to clinical asthmatic samples to potentially confirm what we’ve found experimentally,” Dr. Short added. “Our study provides the first evidence that asthma may influence the evolution of the influenza virus, and — transmission permitting — could lead to the emergence of more pathogenic strains into the community.”
She explained, “It’s therefore really important to remember that host-viral interactions are bidirectional and that host co-morbidities can influence the evolution of influenza virus.” The article was originally published Tuesday on Science Daily.