"We have more cases this year than the last four," says Russell Hopkins of the Northeast Texas Public Health District.
That's because this year's vaccine didn't match the dominant strain of the virus currently circulating.
"What's happened is something we call antigenic drift, meaning the virus has changed ever so slightly, but enough that our immune systems are not really recognizing them," says Dr. Jeff Levin of UT Health Northeast.
When it comes to flu vaccines, Hopkins says science is usually a step behind. "They're looking in places like Southeast Asia [where the] flu season precedes ours. Then the manufactures are told about what strains they would like to see in a flu vaccine," he says.
But Dr. Levin of UT Health Northeast says a universal flu shot could change all that. "There is work going on to see if, perhaps a different kind of vaccine could be developed maybe against a different part of the flu virus, one that is not so subject to this antigenic drift or to change as readily from one year to the next," he says.
That would mean longer-lasting protection against both seasonal and new influenza viruses.
"The problem is getting that efficacy for that long. New strains come every year and they do drift. It only take a couple of weeks for a flu virus to mutate into something else," says Hopkins.
"It's an interesting idea, an important idea and that work has to be done, but it's not quite ready for use on a widespread basis," adds Dr. Levin.
The universal vaccine will go into clinical trials later this year.
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