But some researchers say part of the problem is tied to how 85 percent of the nation's flu vaccine doses are made.
Preliminary figures released Thursday suggest this year's flu vaccine is 36 percent effective overall, and only 25 percent effective against this season's most dominant strain, Type A H3N2. Over the past 10 years, at best it was 60 percent effective and at worst was about 20 percent effective, according to CDC data.
The vaccine was more effective against H1N1, which is also circulating. It's 42 percent effective against influenza B viruses and 67 percent effective against H1N1 viruses, according to the results of a study involving about 4,600 people. A study a few years back looking at H3N2 protection over a number of years found that, on average, its effectiveness hovered around 32 percent or 33 percent.
Producing flu shots is a long, complex process.
"For this season, only 20 percent [of children who died from the flu] have been vaccinated, and half of these children were otherwise healthy", he said. They discovered that in the young, more immune cells called monocytes were recruited to the lungs, and that the gene expression profiles of these cells had more inflammatory features, causing greater inflammation and more severe lung injury. Studies in those two countries showed the vaccine only prevented 10 percent or 17 percent of H3N2 cases. The risk of serious illness in the 6 months to 8 years age group was reduced by 59 percent among children who were infected with the H3N2 strain.
The flu season normally runs October through May.
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The remaining 2.6 percent represents other constituents, such as board members, life members and fan representatives. Cordeiro, 61, replaces Sunil Gulati , who had been at the helm of the federation for the past two decades.
Given how contagious the flu has proven to be, a vaccination that prevents even one person from contracting the flu would prevent multitudes of others contracting it from them.
This year, middle-aged people are being stricken at almost twice the rate seen in 2014-2015, although health officials aren't sure why. A total of 11,230 people have died from the flu this season alone.
The CDC expects high levels of flu activity to continue for several more weeks. During each of those seasons, flu accounted for around 710,000 hospitalizations and 56,000 deaths.
Flu-linked hospitalization rates continue to rise - from 51.5 per 100,000 people for the week ending January 27 to 59.9 per 100,000 people for the week ending February 3.
"Our best advice is to get a flu shot if you haven't already", Stumpf said.
Doctor visits also are up.