Monique George, MD

Improvise. Adapt. Overcome.

Influenza season is here! The CDC says California has ‘high activity’ of flu and the California Influenza Surveillance Program says we’re ‘above expected level’ for this time of year. If you’ve worked in clinic lately you will have seen this first hand. Where I work, we’ve seen record numbers of clinic visits and the hospital is admitting high numbers of influenza patients.

What are your patients saying about the flu vaccine? Some of mine are extra eager to receive it and others have heard it’s not effective at all. The CDC has tracked the vaccine effectiveness since 2004. Its effectiveness ranges from 10-60%. In years where it is well matched to the flu strains it’s 40-60% effective. Flu vaccines tend to work better against influenza B and influenza A(H1N1) viruses and offer lower protection against influenza A(H3N2).

Flu improvises, it adapts, it overcomes. H3N2 undergoes more frequent antigenic changes compared to the other strains. In the time between the vaccine research, manufacturing, and deployment phases the H3N2 virus is more likely than the others to have mutated and overcome the immunity acquired from a given year’s vaccine. And that’s what we’re seeing happen.

Currently, the most common strain is Influenza A H3N2. In California, Influenza A made up 80% of the tested specimens in the first week of January, the most recently released data from clinical sentinel laboratories. When subtyped, H3N2 is about 94% of influenza A strains right now.

So should we give up on vaccination? It’s not just about flu prevention; mitigation is part of the strategy. A 2017 study in the journal Clinical Infectious Diseases showed that the flu vaccination reduced deaths, intensive care unit admissions, ICU length of stay and overall duration of hospitalization among hospitalized flu patients. An unvaccinated hospitalized flu patient was two to five times more likely to die than someone who had been vaccinated. So keep up your efforts!

We may be past this year’s peak flu in adults although like prior years pediatric flu numbers may still be climbing. It will improve soon! As you climb out of the ‘flu trenches’ consider coming to the CAFP All Members Advocacy Meeting in Sacramento. It’s March 10-12 and a great chance to meet new colleagues or catch up with old friends. Let’s celebrate all the hard work we do for our patients day in and out. If we continue to advocate for our patients and our specialty on a regional and national level we can improvise, adapt, and overcome together!