In Brief

Here's How Many People Have Caught the Flu So Far This Season (Hint: It's a Lot)

A person sick with a cold sitting on couch.
(Image credit: Shutterstock)

We're in the midst of flu season, and millions of people have caught the virus already.

Influenza has sickened an estimated 6 million to 7 million Americans since October, according to new data from the Centers for Disease Control and Prevention (CDC).

Although health officials closely track the flu every year, this is the first time the CDC has provided estimates on the number of flu illnesses in the midst of flu season, the agency said in a statement released today (Jan. 11). Typically, the CDC waits until the end of flu season before calculating the estimates.

The new data also show that, since October, an estimated 2.9 million to 3.5 million people have gone to the doctor because of the flu, and 69,000 to 84,000 people have been hospitalized due to the illness.

The estimates are based on rates of confirmed influenza hospitalizations that are obtained from a surveillance network that covers about 8.5 percent of the U.S. population, or about 27 million people, the CDC said.

The estimates will be updated throughout the flu season.

The number of flu illnesses and hospitalizations can vary widely each year depending on many factors, including the types of viruses circulating, how early the season starts, how well the flu vaccine works to prevent the illness and how many people get vaccinated. Since 2010, the yearly total number of flu cases has ranged from 9.3 million during the 2011-2012 season to 49 million during the 2017-2018 season, according to the CDC. (This season's estimates cannot be compared to previous seasons' estimates because the current flu season is still ongoing.)

The CDC recommends the flu vaccine for everyone ages 6 months and older to prevent the flu.

Originally published on Live Science.

Rachael Rettner

Rachael is a Live Science contributor, and was a former channel editor and senior writer for Live Science between 2010 and 2022. She has a master's degree in journalism from New York University's Science, Health and Environmental Reporting Program. She also holds a B.S. in molecular biology and an M.S. in biology from the University of California, San Diego. Her work has appeared in Scienceline, The Washington Post and Scientific American.