By Deidre McPhillips, CNN
Most US states suffer from high or very high flu activity, and levels continue to rise across the country.
“The flu season is just starting, so I think it’s really hard to say exactly how it’s going to play out,” Dr. Michael Osterholm, director of the Center for Infectious Diseases Research and Policy at the University of Minnesota, told CNN on Tuesday. “What we are seeing right now is a very rapid escalation of cases.”
The US Centers for Disease Control and Prevention (CDC) estimates there have been at least 7.5 million cases, 81,000 hospitalizations and 3,100 deaths from the flu this season, according to an update released Tuesday with data through Dec. 20. At least eight children have died from the flu this season.
States with the highest levels of flu activity include Colorado, Louisiana, New Jersey, New York and South Carolina, according to the CDC.
Trends are increasing in key surveillance indicators: Laboratory testing, outpatient facility visits, hospitalizations, and mortality are all higher than in the CDC’s previous weekly update.
Surveillance system shows flu hospitalizations have doubled; More than 19,000 people were hospitalized with the flu during the most recent week, up from about 9,900 the week before.
The CDC states that “severity indicators remain low at this time, but influenza activity is expected to continue for several weeks.”
Influenza A(H3N2) viruses are the most reported, and additional genetic testing suggests that a new flu variant—called subclade K—appears to be behind the vast majority of cases in the U.S. After causing a high number of cases in other parts of the world, subclade K was nicknamed “super flu.”
“This is a different strain than we’ve seen in previous years,” Osterholm said. I wouldn’t call it a “super strain,” he said, but “I would say it certainly challenges our prior immunity, in terms of protection.”
This new variant was not included in this year’s flu vaccines because it was identified after scientists chose which strains to include, but the vaccines contain related strains and, globally, appear to be working quite well against the variant.
The CDC recommends that everyone 6 months and older get the flu vaccine each season, but vaccination rates have been declining in recent years. Only 130 million flu vaccines have been distributed this season, according to CDC data, 13 million fewer doses than at this point last year. Additional data suggests that only about 17% of children and 23% of adults had received their seasonal flu vaccine by the end of November.
Osterholm encourages people who have not gotten a flu shot to act quickly as the virus is “sweeping” the country.
“It’s not too late to get the flu vaccine,” he said. “It doesn’t guarantee that you won’t get the flu. It doesn’t guarantee that you won’t get sick, but it’s certainly a big improvement over what the outcome could be, whether it’s getting very sick or dying.”
The-CNN-Wire
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