ST. LOUIS COUNTY, Mo. — New data shows flu cases in St. Louis County and St. Charles County have spiked sharply since the beginning of 2020.

St. Louis County's most recent flu report shows that the county has had more than 3,200 flu cases since January. That makes up a large majority of the 3,837 total flu cases the county has had this season.

St. Charles County's flu report shows it has seen 1,981 cases this season -- and 560 of those cases were reported in the second week of February alone. Of those cases, 38% admitted to not receiving a flu shot for the 2019-2020 flu season.

Outdated City of St. Louis figures show 578 flu cases for this season. Updated numbers for the city are expected to be released on Friday

The Centers for Disease Control said Missouri and other states are experiencing a high level of "influenza-like illness" activity as of February.

The St. Charles County Department of Public Health said most people can spread the flu one day before showing symptoms and up to five to seven days after symptoms begin. Research suggests taking Tamiflu can reduce the infectious period by one day, the health department said.

Here are some basic tips to keep yourself healthy during flu season: Wash your hands, cover your mouth and nose, take Vitamin C and be sure to get good rest.

Local Walgreens and CVS pharmacies are offering free flu shots to those who have insurance.

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