National Wastewater Surveillance of Wild-type Measles Virus to Support Measles Outbreak Response – United States, March-December 2025
- Presentation Day/Time: Wednesday, April 22, 2:05 PM
- Presenter: Kaitlin Taibl, PhD, MSPH, National Center for Emerging and Zoonotic Infectious Diseases, Division of Infectious Disease Readiness and Innovation
The Issue
- Measles is one of the most contagious infectious diseases; wild-type measles virus (MeV-wt) can infect up to 90% of exposed persons who don't have immunity. During January–February 2025, the United States reported more confirmed cases of measles than in all of 2024.
What We Did
- We examined how the National Wastewater Surveillance System (NWSS) integrated MeV-wt wastewater testing during the 2025 measles outbreak response to support state, tribal, local, and territorial jurisdictions' public health action.
What We Found
- Over 27,000 wastewater samples were tested for MeV-wt. Twenty-five jurisdictions (43%) implemented MeV-wt wastewater testing before a confirmed measles case was reported, which provided an opportunity for early alerts to potential community transmission. Eighteen jurisdictions (31%) implemented MeV-wt wastewater testing after a confirmed measles case, which provided data for monitoring ongoing community transmission. Fifteen jurisdictions (26%) implemented MeV-wt wastewater testing and have not yet identified a confirmed measles case. A total of 143 wastewater samples from 21 jurisdictions have detected MeV-wt.
What This Means
- National wastewater surveillance of MeV-wt provided actionable insights for approximately 600 U.S. communities as they responded to the 2025 measles outbreak. Expansion of MeV-wt wastewater testing in communities at high risk for a measles outbreak, including those with low vaccination coverage, can provide early warning about community transmission.
