Respiratory syncytial virus activity has increased across the Southeast in recent weeks, suggesting the U.S. will see a national uptick within several months, according to a Sept. 5 CDC health alert.
Nationwide, RSV test positivity has remained below the season onset threshold of 3 percent for two consecutive weeks. However, test positivity has increased in Florida since late July, and the three-week moving average has been greater than 5 percent for the last month. RSV hospitalizations also increased in Georgia in August.
"Historically, such regional increases have predicted the beginning of RSV season nationally, with increased RSV activity spreading north and west over the following [two to three] months," the CDC said.
Last year, RSV cases started to rise in summer before peaking unseasonably early in October and November. Despite the atypical timing — caused by COVID-19-related disruptions — RSV activity continued its geographic pattern of starting in Florida and the southeast before spreading to northern and western parts of the U.S., according to the CDC.
Clinicians should prepare to implement new RSV prevention options ahead of the 2023-24 season, the CDC said. This year marks the first timeRSV vaccines will be available for adults 60 and older, a group that is at high risk of severe disease. A monoclonal antibody will also be available for infants and toddlers.