Flu Vaccine Mismatch Doesn’t Mean It’s Not Effective, Health Officials Say

Jan 14, 2020, 9:29 PM | Updated: 9:39 pm

SALT LAKE CITY, Utah – This year’s flu vaccine is not a very good match for influenza B, according to data from the CDC, but an influenza specialist at Primary Children’s Hospital said the vaccine can still save your child’s life.

Flu analyses by the CDC showed the vaccine may not be as well matched genetically to the virus as they had hoped in fighting influenza B. However, that does not necessarily mean it doesn’t protect as well.

“We know a lot of people are getting sick with the flu. So, now is a really good time to take action,” said Keegan McCaffrey, an influenza epidemiologist with the Utah Department of Health.

He said the flu season is intensifying in Utah but officials have seen a normal level of hospitalizations, so far.

According to CDC data, there’s a 58% chance the vaccine is genetically well-matched to the influenza B virus, leaving a 42% chance that it’s not.

Influenza B represents about two-thirds of Utah cases, McCaffrey said.

“It’s why influenza surveillance is important,” he said. “We’ve been tracking this new B virus for the last couple of years, and this is the first time that we’ve seen it really spreading in Utah, in the U.S.”

“The flu shot is not a perfect vaccine,” said Dr. Andrew Pavia with University of Utah Health and Primary Children’s Hospital. “So, people will always be at some risk of getting flu even if they’ve had the vaccine.”

Pavia, chief of Pediatric Diseases at Primary Children’s Hospital, has extensive experience with the influenza virus and said the mismatch in genetics is not the same as a mismatch in protection.

“We’re concerned that this year’s efficacy may not be as good as it is in previous years,” Pavia said. “Even if it were really good protection, influenza B can be very dangerous and children.”

Officials said they’ll know more about how effective the vaccine is next month.

“We know that it’s not a total mismatch from the shot, and we know that the shot is still the best way to protect yourself,” McCaffrey said.

“The flu shot is like a seatbelt,” Pavia said. “It isn’t going to protect you against every crash in every circumstance. But, it reduces your chances of dying, or being severely injured with (the) flu.”

To protect yourself, and those around you: get a flu shot, stay home if you’re sick, and call your doctor if you do get sick.

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Flu Vaccine Mismatch Doesn’t Mean It’s Not Effective, Health Officials Say