Aggressive flu strain spreads across U.S., with experts predicting more cases after holiday travel
The new variant is not expected to be fully covered by this year’s vaccine.
NASHVILLE, Tenn. (WSMV) - Flu cases have doubled over the past month as a new aggressive strain spreads across the country, according to the CDC.
The new mutated flu strain, known as H3N2 subclade K, hasn’t been officially reported in Tennessee yet, but doctors said that will probably change after so many people traveled over the holidays.
More than 4.6 million people have already gotten the flu across the country, with hospitalizations and deaths rising, the CDC said.
“Flu is breaking out all over,” said Dr. William Schaffner of Vanderbilt University Medical Center.
The new virus is changing rapidly and is not fully covered by this year’s flu shot. Schaffner said the new strain is especially dangerous for kids who are more likely to get the virus if they are not vaccinated and can spread it to other people more easily.
“In the laboratory, it really looks as though the vaccine will continue to protect us against severe disease. Of course, that’s what the vaccine is designed to do,” Schaffner said. “It can’t prevent all the milder infections, but it really continues to be useful in preventing us from being hospitalized and going to the intensive care unit or the cemetery.”
Local emergency departments see increasing cases
In just the past two reported weeks, Tennessee has gone from minimal flu cases to the CDC’s moderate level. Places like Colorado, Louisiana, New Jersey and New York are seeing high case levels.
Emergency department traffic for respiratory infections in Davidson County is currently low but increasing, specifically around flu and RSV, according to Metro Public Health Department data. Wastewater surveillance shows a similar pattern of rising cases.
Dr. Schaffner said flu and other virus cases are going to get worse after people traveled to see family over the holidays.
“COVID is picking up a little bit, RSV is picking up a little bit and common colds are out there,” Schaffner said about holiday gathering concerns. “So many of us get indoors, close to each other, and that makes it easier for the virus to get there from one person to another.”
Prevention and treatment recommendations
If you traveled to any of those high-case states, doctors said you need to watch for symptoms like fever, chills or headache. It’s also a good idea to wear a face mask for a couple days and wash your hands frequently.
Schaffner said flu cases do not spread uniformly, but normally come in waves to different parts of the country.
Flu shots remain available at pharmacies and clinics across Davidson County, including Metro Public Health Department preventive health clinics.
“If you haven’t been vaccinated, run, do not walk, and get yourself vaccine. Because we’re going to have flu with us for another three months,” Schaffner said.
He said it’s important to avoid people who are coughing and sneezing, and if you get sick, stay home from more holiday gatherings.
If you start having symptoms, Schaffner recommends seeking medical care quickly. Doctors can prescribe anti-flu medications that can help with the disease and keep people out of the hospital, but they need to be started as fast as possible to have the largest impact.
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