Scientists may have uncovered a way to track the ever-evolving flu virus buried in 10-year-old snot. In an effort to understand how the flu virus rapidly mutates — which leaves scientists constantly scrambling to come up with a new flu vaccine — researchers decided to study four cancer patients' snot, which had been collected a decade ago and frozen.
Because cancer patients tend to come down with the flu for a longer period of time than healthy individuals, the scientists had a longer window of time to observe the mutating virus. In healthy humans, the immune system typically eradicates the flu virus before it undergoes too much mutation, making it harder to track what is coming next in the flu's evolution.
The team "deep sequenced for all the different mutants of one strain of flu called H3N2," Wiredreports. Initially, biochemist Jesse Bloom said the research team expected "the type of evolution that flu undergoes in any individuals ... might end up being very idiosyncratic."
Instead, they saw similar mutations occurring in the viruses within each of the patients' snot — even though the patients weren't all sick at the same time. Moreover, some of those mutations ended up being the same mutations that occurred worldwide in flu outbreaks just years later. Those four patients "were microcosms for the great world when it came to flu evolution," The Atlanticexplained.
The continued deep sequencing of mutations in patients with drawn-out flu infections — a group that also includes pregnant women, children, and obese people — could help scientists get a step ahead of next year's flu. Becca Stanek