For this flu season, experts might've mismatched the strains

Every year, flu experts try to predict which strains will make people sick the following winter so they can develop the vaccine.

The selections that officials made last week for the next Southern Hemisphere vaccine suggest that two of four viruses (influenza A/H3N2 and the influenza B/Victoria virus) in the Northern Hemisphere vaccine might be mismatched.

For Americans and others in the Northern hemisphere, the flu vaccine has four dead viruses to protect against both influenza A viruses - H3N2 and H1N1 - and either both or one of the influenza B viruses, B/Victoria and B/Yamagata.

"Even if the H3N2 component isn't well matched, the others may be very effective against the other circulating flu viruses," said Texas Department of State Health Services' Lara Anton.

She said the World Health Organization helps keep an eye of both Southern and Northern hemispheres--which have flu seasons at different times of the year.

"The flu vaccine has three or four components. Most of the ones we see now are the quadrivalent, that has the four components. And often we see multiple flu viruses circulating throughout the season," said Anton.

In the Northern Hemisphere, this flu season could be dominated by H1N1 viruses. H3N2 has been fairly active the last few years.

It's still too soon to tell if the possible mismatch will add to the severity of the flu season or not.