More Americans have been stricken with the flu this year than last, with nearly a quarter more cases so far this season than in 2020, according to a Walgreens analysis of its own sales of flu medications.  

“To date, overall flu activity is 23% higher nationwide when compared to the 2020-2021 flu season,” the pharmacy chain stated in a news release Monday. 

The jump in influenza cases largely reflects the historically low levels of flu last year as Americans sheltered in place, wore masks and got a record number of flu shots amid the pandemic, Walgreens Chief Medical Officer Kevin Ban noted. 

Pandemic precautions, like wearing masks and social distancing, helped stop the spread of flu and other common respiratory viruses last season, but experts are warning we could see what they are calling a “twindemic” of COVID-19 and flu this coming winter.

“With many regions loosening COVID mitigation efforts and people spending more time together in person, we may see an uptick in flu activity,” Ban cautioned. “It remains critically important to get vaccinated against the flu before it spreads in your community.”

The Centers for Disease Control and Prevention recommends getting a flu shot by the end of October to reduce the risk from the contagious respiratory illness, which killed an estimated 20,000 Americans last flu season. The elderly, very young, and those with asthma and other chronic conditions are particularly vulnerable. 

Flu vaccination prevents tens of thousands of hospitalizations each year and can significantly reduce a child’s risk of dying from influenza, according to the CDC. 

According to an online “Flu Index” map maintained by Walgreens, Las Vegas and Nevada topped the list of cities and states for what the pharmacy chain calls “flu activity” during the week of October 3, likely in part due to the gambling mecca being a tourist destination. The retailer bases its flu findings on sales of antiviral medications used to treat influenza. Walgreens, with around 9,200 stores, is the nation’s second-largest pharmacy chain, behind CVS Health.

Multiple metro areas in Texas also rank high for flu activity, with the Lone Star state placing third behind Mississippi among the top 10 states. Walgreens says it is able to meet customer demand for antivirals used to treat influenza at this time.