Flu activity across the United States dropped for the second week in a row, even as seven more children died from the illness, the Centers for Disease Control and Prevention reported Friday.

This season has been particularly hard on children and young people, due to a strain of the virus called B/Victoria. This strain has been the most common this season so far, but in recent weeks, another strain, H1N1, has ticked upwards, and is now seen at a roughly equal rate as the B strain, the CDC reported. H1N1 is an influenza A strain that also commonly infects younger people.

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The CDC estimates that at least 13 million people have had the flu this season, with roughly 120,000 hospitalizations and 6,600 deaths. Thirty-nine children have died, up from 32 last week.

The number of hospitalizations and deaths are key indicators for how severe the flu is; the CDC noted that the current estimates are not considered high for this point in the season.

The latest CDC #FluView says that #flu activity decreased for the second week in a row, but still remains high with the proportion of influenza A(H1N1) viruses increasing.



Flu activity is expected to continue for several weeks.



Learn more: https://t.co/upgRKTHXEi pic.twitter.com/b9YNYaIsle — CDC Flu (@CDCFlu) January 17, 2020

And there are signs that flu activity is slowing: The percentage of doctors' office visits for flu-like illnesses decreased from the previous week, and the percentage of lab samples that tested positive for the flu also ticked down slightly. This is the second week in a row that flu activity has dropped, the CDC tweeted Friday.

Still, "flu activity is expected to continue for several weeks," the agency tweeted, and it's still too early to know whether the season has peaked or activity will pick up again. Last year saw a second flu peak late in the season.

Official estimates are not yet available for how well this season's flu shot works. Infectious disease experts say this year's vaccine seems to be a good match for one of the strains circulating — the influenza A H1N1 — but not as good a match for the B/Victoria strain, which has been responsible for a high percentage of the illnesses so far. Still, the vaccine remains the best way to protect against influenza complications.

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