Eleven states are experiencing very high levels of flu and some schools have been closed by the burden on students and staff.
Flu cases are surging across the nation, closing nearly a dozen schools and swamping hospitals in some states.
At least 20 million cases, 310,000 hospitalizations and 13,000 deaths -- 57 of them children -- have been reported for this flu season, which began in October, according to data released by the Centers for Disease Control and Prevention on Friday.
Eleven states are experiencing the highest level of flu activity, according to the CDC. New York, one of the states experiencing a surge in cases, reported more than 51,000 positive flu tests during the week ending Jan. 25, a 6 percent increase from the previous week. About 3,000 people were hospitalized with the flu that same week, an 11 percent rise compared with the week before.
Inessa Gendlina, a hospital epidemiologist at Montefiore Medical Center in New York attributed the increase to fewer people wearing masks, a less effective influenza vaccine this year and fewer mitigation strategies such as people social distancing and staying home when a person is sick.
"We're hoping that it's going to start turning around, probably in the next week or two, but it's definitely challenging to be able to predict now," Gendlina said. "Flu seasons are like snowflakes. No flu seasons are exactly the same."
About 45 percent of children and adults received a flu shot this season, a decrease compared with the same time in the 2023-2024 season. Gendlina encouraged people who have yet to receive their flu vaccine to do so.
"It's definitely not too late and it's definitely time if somebody hasn't gotten their flu vaccine yet. Today is the day," said Gendlina.
The brunt of the flu this season has impacted schools across the country, forcing some to close temporarily as outbreaks spread among students and staff.
On Friday, St. Peter Catholic School in Canton, Ohio, said it would be closed "due to an excessive number of staff and student illnesses." While the school had originally planned to reopen on Monday, it remained closed due to the continued prevalence of illness among its staff.
While the rise in cases has sparked concern among some, health experts say the current trend aligns closely with a typical flu season.
Mark J. Mulligan, chief of infectious disease and director of the vaccine center at NYU Langone Health, said the flu generally peaks in February, so while the numbers are high, he is not concerned.
"We're still seeing some of the aftereffects of covid when people didn't get those exposures during that year," Mulligan said.
Health officials continue to stress the importance of basic preventive measures to minimize the spread of the flu. An annual flu vaccine remains the most effective way to reduce the risk of severe illness, especially for young children, the elderly and those with underlying health conditions.
"The flu vaccine needs to be improved, but it's the best thing we have right now," Mulligan said.
Experts say a communication pause has made it increasingly difficult to track and understand how the disease spreads, leaving both medical professionals and the public with limited guidance.
On Jan. 21, the Trump administration paused all external communications from health agencies though some have been reinstated.
Historically, the CDC has issued these alerts to inform health-care providers about emerging health threats and seasonal surges in illnesses such as the flu.
These alerts are crucial in helping doctors recognize infection patterns and prepare for potential increases in patient volume. Without clear updates from federal agencies, many health professionals said they have had to rely on piecemeal information, making it harder to coordinate an effective response.
Zachary Rubin, a pediatric infectious disease physician in Illinois, said the absence of these updates has made his job more difficult.
"When we can't find the information combating any type of public health issue, whether it's influenza or an emerging pandemic, we're not able to communicate this information to the general public," Rubin said. "It's not proper health communication that's going on."
The lack of federal guidance has also affected public awareness efforts, making it harder to convey the severity of the flu season to communities that may not see the full picture, according to medical providers. Many doctors and public health officials are calling for a return to regular health alerts.
Dan Keating contributed to this report.