The Washington State Department of Health (DOH) has extended RSV season guidance through April 30, 2026, directing healthcare providers to keep administering RSV monoclonal antibody treatments to eligible infants. The advisory was issued March 17, 2026, through Thurston County Public Health.
Providers are asked to assess and immunize young children with nirsevimab or clesrovimab before the April 30 deadline. All infants under 8 months are eligible unless they have already received a dose, are protected through maternal RSV vaccination given at least two weeks before birth, or have a medical contraindication. Higher-risk infants ages 8 to 19 months who are in their second RSV season may also qualify for nirsevimab.
This season's RSV activity in Washington started later than usual. Emergency department visits statewide hit the activity threshold in December 2025, compared to October or November in previous years. Hospitalization rates for young children in Washington remain elevated.
RSV is the leading cause of infant hospitalization in the United States. Families with eligible infants are encouraged to contact their healthcare provider before April 30, 2026, to confirm their child has received the recommended protection.