Measles wastewater testing will be expanding across Virginia. Starting in May 2026, in partnership with the Division of Consolidated Laboratory Services (DCLS), VDH began testing wastewater collected from about 30 Virginia wastewater treatment plants for measles virus. Results are posted on CDC’s Wastewater Data for Measles page.
Why look for diseases in wastewater? People infected with measles can pass viral material in their stool before symptoms begin. When a person with an infection uses the toilet, sink, or shower, viral particles can enter the wastewater system. A laboratory test can detect these viral particles in a sample of wastewater. A positive wastewater measurement shows that measles might be present in a community. Testing wastewater for diseases can provide alerts about disease trends even when people do not show symptoms, seek medical care or testing.
A positive measles wastewater result does not tell us:
- Who is sick and the severity of their illness
- How many people are sick
- Whether the sick person(s) lives in the community or was travelling through
If there is a measles detection in wastewater near you, protect yourself by:
- Checking your measles immunity status
- Avoiding contact with people who are sick
- Practicing good respiratory etiquette (e.g., covering your mouth when coughing)
Wastewater testing is most useful when we compare it with other clinical information. This includes hospital visits and clinical laboratory tests. If measles is not detected in wastewater, it does not guarantee that no measles infections are present in the community.
Wastewater monitoring can provide an early signal to public health officials about measles activity in a community. This is especially critical with measles cases on the rise in the United States and in Virginia. As of May 26, 2026, 1,952 measles cases have been reported nationally, including 54 cases in Virginia.
Cases might increase in the summer as more people travel. The MMR vaccine is your best protection against measles.
To learn more about the Virginia Department of Health’s measles response visit www.vdh.virginia.gov/measles/.