Flu Season Shows First Signs of Slowing

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HealthDay Reporter

FRIDAY, Feb. 16, 2018 (HealthDay News) -- While this flu season is still one of the worst seen in years, the first signs that infection rates are starting to level off were reported by U.S. health officials on Friday.

As of Feb. 10, a total of 43 states continued to experience widespread flu activity, down from 48 the week before, according to the latest surveillance report from the U.S. Centers for Disease Control and Prevention.

There was also a slight drop in doctor visits for flu-like illness: 7.5 percent of patient visits during the week ending Feb. 10, down from 7.7 percent of patient visits the week before.

But the news was not all good, and it doesn't look like the flu season is over yet.

Flu-linked hospitalization rates continued to rise -- from 59.9 per 100,000 people for the week ending Feb. 3, to 67.9 per 100,000 people for the week ending Feb. 10, the findings showed.

Pediatric flu deaths are also still increasing, with 84 children now dead from the flu so far this season, according to the CDC.

Just Thursday, CDC officials pinpointed one reason why this flu season has been so brutal: the flu vaccine is only 25 percent effective against H3N2 influenza, which is causing most flu cases this year.

Among children aged 6 months through 8 years old, however, the vaccine's effectiveness is 59 percent, the agency reported.

Despite the poor match of the vaccine to the most common strain of flu, the CDC is still urging people who haven't gotten a flu shot to get one, because the vaccine is more effective against other types of flu.

For instance, the vaccine is 67 percent effective against the H1N1 flu, which was the 2009 pandemic flu and is still around. In addition, the vaccine is 42 percent effective against the influenza B viruses, which are also circulating, the researchers said.

The flu shot's overall effectiveness against all strains was pegged at 36 percent, the CDC said.

But Dr. Daniel Jernigan, director of the agency's influenza division, stressed earlier this month that getting the flu shot is still worthwhile, especially for kids.

"For this season, only 20 percent [of children who died from the flu] have been vaccinated, and half of these children were otherwise healthy," he said. The deaths were associated with H3N2, H1N1 and influenza B strains -- "all of the different types of influenza are causing these deaths," Jernigan noted.

Other countries also are experiencing a bad flu season because of the vaccine's ineffectiveness against the H3N2 virus. In Australia, for example, its effectiveness against H3N2 was pegged at 10 percent, and in Canada it has been between 10 to 20 percent.

The CDC recommends that everyone aged 6 months and older get a flu shot. The flu season probably won't start winding down immediately, the agency explained.

Some people who get vaccinated will still get sick with flu, but may have milder cases. The CDC advises that people who are very sick or who are at high risk for serious flu complications should get antiviral medications as soon as flu symptoms appear.

The CDC's flu vaccine update was published in the agency's Feb. 16 issue of the Morbidity and Mortality Weekly Report.

More information

The U.S. Centers for Disease Control and Prevention has more about the flu.

SOURCES: Feb. 16, 2018, Morbidity and Mortality Weekly Report; Feb. 16, 2018, FluView, online

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