RSV hospitalizations are now rising in seniors, and only 14.3% have received the new vaccine.
Health officials are releasing 77,000 more doses, with supply stretched by higher-than-expected demand for the new tool for protecting newborns.
The Traveler-based Genomic Surveillance program will expand to provide early detection of flu and other respiratory viruses.
The drug manufacturer said that demand for 100-milligram doses has been higher than anticipated.
The injectable monoclonal antibody is one of two new prevention strategies to cut the RSV burden in newborns.
Early sharp rises in some South American countries put pressure on healthcare systems.
Though the group welcomed new tools for cutting RSV in infants, they acknowledged complex practice challenges ahead.
Wastewater testing rose in prominence during the COVID-19 pandemic.
Interest in getting the newly approved RSV vaccine varies by factors such as age and underlying health status, according to a survey of older US adults.
FDA's approval is for use of the vaccine, called Abrysvo, at 32 to 36 weeks gestational age of pregnancy.
