The headlines may all be about the California measles outbreak, but influenza is still causing its annual epidemic of misery, according to the latest federal data.
Flu’s widespread in 44 states, regional and local in the rest. Eleven more children have died from flu, bringing the total for this season to 56, the Centers for Disease Control and Prevention reports. Last season, 109 children died from flu.
Nine percent of all deaths that have been reported are due to pneumonia and influenza, and that counts as an epidemic for mid-January, CDC said.
About 20 percent of people who got a flu test got a positive result, meaning that most respiratory infections causing serious illness were something else. That’s normal – there are hundreds of respiratory viruses that make people sick and most are never diagnosed.
The flu season started a little early this year and the first strain of virus to really get a foothold on the population was one strain of H3N2 – a type that usually means trouble because it tends to be a little harsher. Worse, it wasn’t the precise strain that’s in this year’s vaccine, meaning even vaccinated people are vulnerable.
Flu mutates all the time and that is why people are advised to get a new flu vaccine every year. Each year, the vaccine is reformulated and protects against either three or four strains of flu. This year’s carries protection against one H3N2 strain, the H1N1 strain that first appeared in 2009, and either one or two B strains.
About a third of samples analyzed from patients show they had an H3N2 infection that matched the vaccine, so the vaccine’s not useless. And about 5 percent of the circulating flu is influenza B. CDC officials say it’s still a good idea to get vaccinated because sometimes influenza B strains can cause a late uptick in flu, in late winter or even early spring.
But only about half the U.S. population ever gets the flu shot.