While flu activity remains high across the United States, CDC's latest FluView report shows a decline in influenza-like illnesses (ILI) in many areas—and experts say "[i]t's pretty clear that there was a peak of activity, but that doesn't mean we won't have another one."

Is it the flu, RSV, or Covid-19? Here's how to tell.

Where the flu season currently stands

For the week ending Dec. 31, 39 states reported high or very high levels of ILI, down from 44 states for the week ending Dec. 24.

According to CDC, Oregon, Nevada, Arizona, Wyoming, Wisconsin, Illinois, Michigan, and Delaware reported moderate levels of ILI. Minnesota, New Hampshire, and Alaska reported minimal levels of ILI, and Hawaii, South Dakota, and West Virginia reported low levels.

For the week ending Dec. 31, 18,954 patients were hospitalized with lab-confirmed cases of the flu—a slight increase over the previous week. Currently, the overall cumulative hospitalization rate of 48.6 per 100,000 for the week ending Dec. 31 remains almost four times higher than the highest rate reported during this same period since the 2010-11 flu season. 

So far, CDC has reported a total of 74 pediatric flu deaths in the 2022-23 flu season, with 13 pediatric deaths associated with ILIs reported for the week ending Dec. 31.

Overall, CDC estimates there have been at least 22 million flu cases during the 2022-2023 season so far, with roughly 230,000 hospitalizations and 14,000 deaths.

Flu cases appear to be trending downward

While flu cases are still high in the United States, the latest numbers suggest they are trending downward.

"It's pretty clear that there was a peak of activity, but that doesn't mean we won't have another one," said Lynnette Brammer, lead of the CDC's domestic influenza surveillance team. "Things could turn around and go back up."

The flu is often hard to predict—and its severity can vary widely from season to season. For instance, while the 2022-2023 season began much earlier than usual, its outcomes have fallen within an expected range so far.

On Friday, White House Covid-19 response coordinator Ashish Jha said health officials will continue monitoring respiratory syncytial virus and flu even as numbers decline.

"Obviously, right now, Covid is the thing that is increasing that we need to pay most attention to," Jha said. (Carbajal, Becker's Hospital Review, 1/6; Goodman/McPhillips, CNN, 1/6)