13 Apr 2026 RSV Season Ends April 15

Based on decreased RSV test positivity and pediatric hospitalizations, the Philadelphia Department of Public Health recommends stopping RSV monoclonal antibody immunization (i.e., nirsevimab and clesrovimab) to all eligible patients on April 15, 2026.

Administration may continue until April 30, 2026, based on clinical judgment. Due to CDC RSV ordering extension, RSV immunization is still available to order from the Vaccines for Children (VFC) program until April 30, 2026.

Please note that if healthy newborns receive RSV immunization in April 2026, they will not be able to receive a dose in Fall 2026 when RSV activity is expected to be elevated (even if they are less than 8 months of age at the time). Protection does wane and typically lasts 5 months.

Unused Immunizations

If you have unexpired doses of RSV at the end of the season, do not discard them. These doses can be safely stored until their expiration date. Unexpired doses can be used when RSV season resumes on October 1, 2026. 

If your nirsevimab expires before October 1, 2026, please process a vaccine return after the expiration date. Use this guide for assistance: Guide to Returning Vaccines.

Need Help?

If you need any assistance with your return, contact dphproviderhelp@phila.gov.

For questions, contact Vaccine & VFC Manager, Alisha Conway, at alisha.conway@phila.gov.