New material claimed to filter flu virus out of air
November 3, 2011
Staying healthy during flu season is about to get easier thanks to researchers at China's Academy of Sciences and Academy of Agricultural Science, and it doesn't involve painful injections. Instead, the team has developed a way to improve air filter technology to specifically target influenza viruses, effectively stopping them before they get inside our bodies and make us ill. The nice thing about air filters is that they work both ways, so sick individuals wearing the modified filters will end up shedding less viruses into the environment too, which can also help reduce the rate of new infections.
In their study recently published online in the journal, Biomacromolecules, researchers Xuebing Li, Peixing Wu et al, point out that worldwide every year, on average, nearly 300,000 succumb to flu viruses. Millions more are sickened, which, aside from the suffering, translates into substantial economic losses.
Antibiotics don't work on viruses and so don't enter the equation, but there are numerous anti-viral drugs (amantadine, oseltamivir, rimantidine and zanamivir, to name a few) which, while initially effective, are beginning to lose some of their clout. It doesn't help that the little buggers are constantly mutating into new strains either, meaning pharmaceuticals and vaccines are always playing catch-up.
Since viruses can only replicate inside of living host cells, Li and his group reasoned that a new approach was needed to help stop these deadly pathogens from multiplying and hit upon an adaptation of the very mechanism viruses use to infect cells.
When a virus targets a host cell, a protein which peppers its outer surface, hemagglutinin (HA), seeks out and binds to multiple sugars or glycans (the bound monosaccharides sialic acid and lactose- SL) on the host's membrane surface. The researchers found that the versatile linear polysaccharide, chitosan, made from the chitin found in crab and shrimp shells, was an ideal substance to bind SL to otherwise pristine filter fibers. As the diagram below shows, viruses now have to run a gauntlet of fibers festooned with the very substance they're attracted to, effectively stopping them in their tracks. That's news that should help all of us breathe just a little bit easier.
The research is published in the ACS journal Biomacromolecules.