Jackson County Public Health has detected measles in the region’s wastewater, prompting officials to warn residents about possible community spread of the virus.
The detection marks the first time measles has been identified in local wastewater since the county began testing sewage for the virus in October 2025. Officials described it as a low-level detection, indicating that at least one infected person used the regional sewage system.
No measles cases have been confirmed in Jackson County so far this year, but preparedness manager Tanya Phillips said the wastewater detection serves as an early warning sign.
“It’s just giving us a heads up that someone in the community has or had measles and they utilized our sewage system,” Phillips said. “It’s just alerting the community.”
She said that while the risk for measles remains low in Jackson County, it is not zero. The Oregon Health Authority classifies counties' measles activity level from "non-detectable" to “high.".
Public health agencies began monitoring wastewater for pathogens during the COVID-19 pandemic. Since then, testing has expanded to include viruses such as influenza and RSV. Oregon State University staff collect and test samples weekly from wastewater treatment facilities in Medford and Ashland.
Jackson County Public Health epidemiologist Steven Bagley said wastewater surveillance can provide broad public health insights from a single sample.
“It’s a helpful tool that can give us an early warning signal if something’s about to happen, allow us to reach out, get some prevention activities going and help our community stay healthy,” Bagley said.
Bagley said wastewater testing could eventually expand to track additional threats, including antimicrobial-resistant bacteria.
Phillips said measles outbreaks have increased nationwide as vaccination rates have declined.
“Measles is one of those infections that we would have considered eradicated,” she said.
Oregon has recorded 20 measles cases this year, according to state health officials. Nationwide, nearly 2,000 cases have been confirmed.
Jackson County Public Health recommends that people who are not fully vaccinated receive the measles, mumps and rubella, or MMR, vaccine.
