June 5, 2026

FOR IMMEDIATE RELEASE

CONTACT: Mike North

209-726-2744 or Mike.North@countyofmerced.com

Public Health Confirms Measles Wastewater Detection in Merced

MERCED—The Merced County Department of Public Health (MCDPH) is reporting the detection of the measles virus in local wastewater from the Merced Wastewater Treatment Plan during routine surveillance. To date, no confirmed clinical case of measles has been identified or confirmed in the community. To see Merced’s wastewater surveillance results, visit: https://data.wastewaterscan.org/.

What is wastewater surveillance?

Wastewater surveillance serves as an early warning sign that can detect viruses shed in bodily waste, often before people develop symptoms or cases are identified through clinical testing. Early detection allows Public Health to inform the healthcare system and residents of viruses that may be in their community. While this tool can help identify the presence of a virus in the community, it cannot determine who is infected, where they live, or how many people are affected. A positive detection may reflect a local case or an infected traveler passing through the area. Currently, there are no confirmed measles cases, and no known case counts linked to this detection. Wastewater surveillance only tests sewage entering treatment facilities and does not indicate contamination of the drinking water supply, which remains safe to drink and use.

What You Need to Know About Measles

Measles spreads easily through the air when an infected person breathes, talks, coughs, or sneezes. The infected person can spread the disease up to four days before a measles rash appears, and up to four days after the rash appears.

Symptoms

Early symptoms of measles can include:

• Fever
• Cough
• Runny nose
• Conjunctivitis (red, watery eyes)

Measles Prevention

Measles is preventable with two doses of the measles, mumps, and rubella (MMR) vaccine, typically given during childhood. Adults need at least one dose of the MMR vaccine after age one.

• Individuals born before 1957 or who had measles as a child are considered immune.
• Anyone born between 1957 and 1967 who is unsure which measles vaccine they received should get at least one dose of the MMR vaccine.

For individuals traveling internationally or in the US where measles is circulating, CDC recommends:

• Infants 6 to 11 months old need one dose of the MMR vaccine.
• Children 12 months and older need two doses of the MMR vaccine.

To obtain the measles vaccination, call your healthcare provider or the Merced County Department of Public Health Clinic at (209) 381-1023 to ensure protection.

Measles Exposure Guidance

MCDPH encourages residents to confirm their measles vaccination status with their healthcare provider or by visiting: https://myvaccinerecord.cdph.ca.gov/ to access their digital vaccine record. If you suspect that you have been exposed to measles, please isolate and contact your healthcare provider immediately.



For more information on measles, please visit:

1. https://www.cdc.gov/measles/index.html
2. https://www.cdph.ca.gov/Programs/CID/DCDC/Pages/Immunization/measles.aspx