ATLANTA — With an unusually severe flu season underway, residents across the eastern United States will be retreating indoors as a wave of arctic air engulfs the region this week. Unfortunately, the flu thrives in these cold conditions, especially when people are confined to close quarters.

The chilly weather fosters an ideal setting for the flu virus to spread.

In cold and dry air, the virus’s protective layer becomes more resilient, allowing it to survive longer and disperse more effectively through the tiny droplets we exhale.

Additionally, cold air challenges our immune system: it dries out the nasal passages and narrows blood vessels in the nose, diminishing the presence of germ-fighting cells that typically capture and destroy viruses.

Add in more time spent indoors—where people are in close contact and ventilation is limited—and winter becomes peak season for flu transmission.

New data released Friday by the CDC shows flu remains high or very high in 44 states.

The data shows 40,000 people were admitted to the hospital for flu the week ending January 3, with seniors and children the most admitted.  Eight children died bringing the total this season to 17.  

The most common type of flu this year is also one which spreads the fastest, according to Dr. Parissa Rabbinafard of Peachtree Dunwoody Medical Associates in Atlanta.  

“A (H3N2) viruses are the main drivers of the increase in flu cases this year.,” she said in a statement. “While influenza B is also circulating, it is doing so at lower levels and influenza A spreads faster and with stronger symptoms than influenza B.”  

Unfortunately, many of the states ranking highest in flu cases, such as Georgia, Ohio and New York will see temperatures plummet over the next 10 days with a series of polar blasts starting Tuesday.  

By Thursday, Cleveland is forecast to see lows in the teens and highs only in the 20s; Atlanta won’t make it out of the 30s; and Buffalo, New York, will also drop into the teens, likely with snow.

If you haven’t gotten a flu vaccine yet, doctors say it isn’t too late.  

“Vaccination is recommended as long as flu viruses are still circulating,” Dr. Rabbinafard said. “Getting a flu shot now can still help protect against influenza and reduce the risk of severe illness, hospitalization or complications.”

Click here to check your local forecast from your trusted weather team.