Health Alert
Respiratory Syncytial Virus (RSV) transmission is continuing in California.
CDPH recommends continuing RSV immunization of eligible infants and young children with RSV monoclonal antibody products through April 30, 2026.
RSV infection is the most common cause for hospitalization in infants in the US.
RSV monoclonal antibody products, nirsevimab (Beyfortus) and clesrovimab (Enflonsia), are highly effective in preventing infant hospitalizations due to RSV.
RSV infections in young children are likely to continue into April 2026: CDPH data show the current 2025-2026 RSV season started later than prior seasons and RSV activity remains elevated. As of 2/28/26, RSV test positivity was 6.8% among all ages and 13.3% among children 0-17 years.
CDPH recommends continuing RSV immunization with RSV antibody products for another month, through April 30, 2026, to:
All infants aged 0 through 7 months, within 1 week of birth, ideally during the birth hospitalization or as soon as possible after discharge (unless prenatal RSV immunization occurred between 32 through 36 weeks of gestation and at least 14 days before delivery)
Nirsevimab or clesrovimab are recommended
Children aged 8 through 19 months at high risk of severe RSV
Only nirsevimab is recommended
The Vaccines for Children (VFC) program provides nirsevimab and clesrovimab at no cost for providers immunizing children who are: Medi-Cal eligible, uninsured, underinsured, and American Indian/Alaska Native.
Under AB144, California regulated health plans are required to cover RSV immunization based on CDPH guidance.
CDPH continues to monitor RSV activity in California to guide recommendations for the remainder of the 2025-2026 season.
American Academy of Pediatrics (AAP): RSV Immunization Administration
CDPH: California Respiratory Virus Dashboard
CDPH: Immunization Recommendations
CDPH: RSV Toolkit