NEW YORK (AP) — Health officials are telling doctors that the flu vaccine may not be very effective this winter.
As flu season begins to ramp up, officials say the vaccine does not protect well against the dominant strain seen most commonly so far this year.
That strain tends to cause more death and illness, especially in the elderly. CDC officials say the vaccine should still provide some protection, but it won't be as good as if the vaccine strain was a match.
Flu vaccine effectiveness tends to vary from year to year. Last winter, flu vaccine was about 60 percent effective overall, which experts consider good.
The Centers for Disease Control and Prevention issued an advisory to doctors about the situation on Wednesday.