Flu hospitalization rate at highest level this time of year since 2010 season: CDC

Louisiana and Hawaii are reporting "moderate" levels of activity.

The flu hospitalization rate in the U.S. is at the highest level for this time of year since the 2010 season, according to an update published Friday from the Centers for Disease Control and Prevention (CDC).

Positive flu tests, emergency room visits and hospitalizations have been increasing since late August and early September, the CDC data shows.

The rate of hospitalizations for this week, while still low, is at its highest level since the 2009-10 season, during the H1N1 "swine flu" pandemic.

Adults above age 65 have the highest rate of hospitalizations followed by adults ages 50-64 and children ages 0-4. 

Louisiana and Hawaii are reporting "moderate" levels of activity while the remaining states are reporting "low" or "minimal" activity.

Despite flu activity increasing in various parts of the country, it still remains relatively low throughout the U.S.

Flu viruses constantly change and the CDC is tracking any notable mutations that may have an impact on illnesses.

"It is too early to know what viruses may predominate or to say whether there might be implications [for] flu vaccine effectiveness this season," the CDC says.

Data from Walgreens suggest that flu activity is tracking about four weeks ahead of recent flu seasons.

States with some of the highest levels currently include California, Florida, Hawaii, Nevada and Washington, according to the pharmacy company's data.

Walgreens uses data including tests, prescription antivirals and over-the-counter cold and flu purchasing trends to predict activity.

The sale of common cold and flu products is up 17%, cough drops up 13%, tea bags up 18%, and at-home COVID and flu tests up 11% year over year.

The CDC recommends everyone aged 6 months and older get their annual flu vaccine with adults aged 65 and older eligible for a higher dose version. 

There are prescription antiviral drugs available that can help treat flu illness -- including reducing the severity and length of sickness -- which are most effective when started as early as possible during the course of illness.