Associated Press February 20, 2020 03:55 PM
It may end up being a bad flu season for kids,
but early signs suggest the vaccine is working OK.
The vaccine has been more than 50% effective in
preventing flu illness severe enough to send a child to the doctor's office,
the U.S. Centers for Disease Control and Prevention said Thursday. Health
experts consider that pretty good.
The vaccines are made each year to protect
against three or four different kinds of flu virus. The ingredients are based
on predictions of what strains will make people sick the following winter. It
doesn't always work out.
This flu season has featured two waves, each
dominated by a different virus. Both of those flu bugs are considered dangerous
to children, but tend not to be as dangerous to the elderly.
Health officials grew worried when it became
clear that the vaccine didn't match the Type B flu strain that ended up causing
most early season illnesses. But the CDC estimates that the vaccine has been
about 50% effective against that strain in children.
And the vaccine has been about 55% effective
among kids against the Type A strain that has caused a second wave of flu
illnesses.
"These estimates are reassuring," said
the CDC's Brendan Flannery, who oversees the agency's system for evaluating flu
vaccine effectiveness.
Vaccines against many infectious diseases aren't
considered successful unless they are at least 90% effective. But flu is
particularly challenging, partly because the virus can so quickly change.
Overall, flu vaccine averages around 40%.
This season, the vaccine has been 45% effective
against both types of flu across all ages.
That can change as the flu season progresses.
Updated vaccine effectiveness numbers are expected later this year.
One troubling finding: This season's vaccine has
been virtually ineffective vs. the Type A virus in younger adults. The reason
is a mystery, but may change as more data comes in, Flannery said.
U.S. health officials have counted 92 child flu
deaths this year, up from the same time last year but fewer than were counted
by this point in 2018. In all, the CDC estimates at least 14,000 Americans have
died of the flu this season.
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