South Carolina has the second-highest flu activity in the country, and Lowcountry hospitals are already feeling the strain weeks before the season's expected peak.

The state trails only Louisiana in flu activity, according to Centers for Disease Control and Prevention (CDC) data for the week ending Oct. 31, first reported by WCBD News 2. South Carolina is classified in the "high" category, according to WYFF4.

Physicians at the Medical University of South Carolina (MUSC) and Roper St. Francis Healthcare say flu, RSV and COVID-19 cases are all climbing, WCBD reported.

"We're seeing plenty of flu in our ERs, which are kind of the leading indicator of where it's the worst," said Dr. Scott Curry, hospital epidemiologist and infectious disease physician at MUSC, according to WCBD.

Curry said about 2.95% of ER patients tested positive for flu that week. He said MUSC would begin implementing mask mandates and additional protocols if that rate rises above 5%, WCBD reported.

Roper St. Francis sees cases double

At Roper St. Francis Healthcare, physicians reported a steady increase in cases since late September, according to WCBD. Nearly 50 flu patients were hospitalized in the past month, and the community test positivity rate more than doubled.

Dr. Robert Oliverio, chief medical officer for physician channel and population health at Roper St. Francis, told WCBD that test positivity climbed from about 5% to 6% earlier in the fall to roughly 12.5%.

"Anything over 10% in the community means that this is a widespread illness, and it could get worse," Oliverio said, according to WCBD.

Roper St. Francis is building a new hospital campus in North Charleston off Mall Drive behind City Hall. That $1.2 billion project broke ground in June 2025 and is expected to open in early 2029, according to Live 5 News.

Some hospitals already tightening rules

Some Prisma Health hospitals elsewhere in the state have begun restricting visitors age 15 and younger and are recommending masks for all visitors, WCBD reported. Lowcountry hospital systems, including MUSC and Roper St. Francis, had not imposed visitor restrictions as of the report.

Nationally, the CDC's weekly surveillance report for the week ending Oct. 31 estimated at least 1.7 million flu illnesses, 25,000 hospitalizations and 1,400 deaths so far this season. The agency noted that early-season activity is higher than typically observed but said an earlier increase does not necessarily lead to a higher seasonal peak.

The CDC reported 8,396 lab-confirmed flu hospitalizations nationally during that week. Adults 65 and older had the highest hospitalization rate at 19.8 per 100,000 population.

Vaccination window still open

The South Carolina Department of Public Health recommends flu vaccination for everyone 6 months and older. The agency also encourages handwashing, staying home when sick and covering coughs, according to the department's Flu Watch page.

Oliverio told WCBD that vaccination reduces the severity of illness even for people without high-risk conditions. "You still have plenty of time to get a vaccine before the holiday season hits in full force," he said, according to WCBD.

Physicians say it takes about two weeks after a flu shot for immunity to develop, WCBD reported.