It's also interesting to note that all mammalian influenza A viruses were thought to have evolved from avian species to begin with.
Once influenza makes the jump to mammals, the virus typically experiences a high amount of continued mutation compared to the stable avian pool.
Back on the subject of testing, note that subtype testing is required to definitively differentiate H5N1 from seasonal influenza.
With the understanding that PCR testing for influenza A can most likely pick up H5N1, consider that some regions are currently seeing 14x higher than normal levels of influenza A in testing, breaking with typical seasonal trends.
Finally, recognize that the D1.1 strain of H5N1 has acquired the PB2 D701N mutation in Nevada, which may allow it to spread better through humans and other mammals (eg., cows).
H5N1 is on the verge of becoming the next global pandemic. Tread carefully.
There's been a sharp increase in unsubtyped influenza A detected in Canada and beyond over the last few weeks.
Compared to the previous two seasons, influenza only passed the epidemic threshold (5% test positivity) in January compared to a October/November start.
What's up? 🧵
By definition, influenza A without a subtype remains unidentified.
However, given that influenza A shares a gene with H5N1, it is still possible that at least some of those positive results are in fact H5N1.
Amid the gloom and doom, I'm excited to share news that gives me hope.
Invivyd has announced positive initial findings from an ongoing clinical trial of a monoclonal antibody to be used as a pre-exposure prophylactic to prevent COVID-19 infections.
Here are the highlights: 🧵
Invivyd has been developing a monoclonal antibody to prevent COVID infection.
The idea is you'd get it once or twice a year and get better protection against COVID than available vaccines.
This could make it much easier to avoid long COVID, especially combined with respirators.
VYD2311 is a monoclonal antibody with neutralization ability against various lineages including XBB.1.5, and it reportedly achieves increased neutralization over pemivibart (pemgarda).
Note: JN.1 neutralization has been confirmed in vitro for pemivibart.