Influenza has arrived.
Some Georgia emergency departments are seeing a 25-30% increase in volumes due to people seeking care for influenza or influenza-like illness.
According to the CDC web site, there is good match between vaccines and the circulating virus strains this year. H1N1 virus strain not being seen much. H3N2 is the predominant Influenza A strain while “Yamagata lineage” is the predominant Influenza B strain in circulation. Note that there is one Influenza B strain circulating that was NOT contained in the vaccine – the “Victoria lineage” which accounts for about 15% of the total samples tested.
For an interesting look into how influenza vaccines are created each year, see this link.
It’s not too late to get vaccinated, but realize that vaccination takes about 1-2 weeks to generate an immune response in your system before it becomes effective.
One side note, there are some medications which may shorten the course of influenza when taken early in the course of the disease. One 2012 Cochrane review questioned the effectiveness of neuraminidase inhibitors (Tamiflu and Relenza) because “60% of patient data from phase III treatment trials of [Tamiflu] have never been published” and because the company that produces Tamiflu – Roche – reportedly ignored five different requests from the researchers to release the information in those studies.
According to the CDC site above, so far there is no resistance to the neuraminidase inhibitors with any of the influenza strains. There is high resistance to the less expensive amantadines in all influenza A samples (influenza B is not sensitive to amantadines).
In other words, if you get the flu, taking amantadine (Symmetrel) or rimantadine (Flumadine) would be just as effective as taking a “ZeePack” (Azithromycin) or as taking red jelly beans in making you feel better.
I’m personally not a big fan of Tamiflu and Relenza. I’ll discuss the above with patients who have influenza, and afterwards if people want to pay $50-$120 for medications that may make them feel better and may shorten the course of the disease by 12-24 hours, I’ll write them the prescription. PT Barnum philosophy in my book.
In our state, Tamiflu and Relenza aren’t on the Medicaid formulary – only amantadine. You’d be surprised how many people demand amantadine prescriptions so that they can take something to help with their symptoms – even though it has little or no effectiveness against the circulating virus strains. Seems that no one cares about amantadine’s side effects. They just want a pill.
I’d prescribe red jelly beans instead, but those aren’t on Medicaid’s formulary, either.
Good thing those folks have insurance, though.
Finally, if you want an interesting influenza anecdote to start up a conversation at parties, this year scientists discovered a new influenza virus that is entirely different from all known influenza A viruses. The hemagglutinin portion of the virus (the “H” part of the influenza designation in “H1N1”, for example) was dubbed H17. The neuraminidase portion of the virus (the “N” in the H1N1 designation) hasn’t been determined. Researchers weren’t able to grow the new influenza virus in any of the traditional methods and believe that the virus would require significant mutations before it is able to infect humans. Just to be safe, though, stay away from Guatemalan fruit bats – which were the reservoir for the new virus.