Most U.S. states are experiencing high or very high influenza activity, and levels continue to increase nationwide.
“Flu season has just begun, so I think it’s hard to say exactly what it’s going to look like,” Dr. Michael Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota, told CNN on Tuesday. “What we’re seeing now is a rapid escalation of cases.”
The Centers for Disease Control and Prevention estimates that at least 7,500,000 people have been sickened by the flu this season, 81,000 have been hospitalized and 3,100 have died, according to the latest data released Tuesday through Dec. 20. At least eight children have died from the flu this season.
According to the CDC, states with the highest flu activity include Colorado, Louisiana, New Jersey, New York and South Carolina.
Trends in key surveillance indicators are increasing: Laboratory tests, outpatient medical visits, hospitalizations and death rates are all higher than in previous weekly updates from the CDC.
A surveillance system shows flu hospitalizations have doubled; more than 19,000 people were hospitalized with the flu in the latest week, up from about 9,900 the week before.
“Severity indicators remain low at this time, but influenza activity is expected to continue for several weeks,” the CDC said.
Staying ahead of the ‘super flu’
Influenza A (H3N2) is the most common virus, and additional genetic testing shows that a new flu variant, called subclade K, appears to be behind the vast majority of cases in the United States. Clade K earned the nickname “superflu” after a large number of cases emerged in other parts of the world.
“This is a different strain than we’ve seen in previous years,” Osterholm said. He wouldn’t call it a “super strain,” but “I would say it does challenge our previous immunity in terms of protecting us.”
The new variant is not included in this year’s flu vaccines because it was identified only after scientists selected which strains to include, but the vaccines contain related strains and, globally, they appear to be effective against this variant.
The CDC recommends that everyone 6 months and older get a flu shot each season, but vaccination rates have been declining in recent years. CDC data shows that only about 130 million doses of flu vaccine have been distributed this quarter, 13 million fewer than the same period last year. Additional data shows that by the end of November, only about 17% of children and 23% of adults had received the seasonal flu vaccine.
Osterholm encouraged people who haven’t gotten a flu shot to act quickly because the virus is “sweeping” the country.
“It’s not too late to get your flu shot,” he said. “It doesn’t guarantee that you won’t get the flu. It doesn’t guarantee that you still won’t get sick, but it’s certainly a big improvement that might otherwise lead to serious illness or death.”
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