Measles Virus Detected at Wastewater Sampling Site in West Hawai’i County

The Hawai‘i Department of Health is closely monitoring a positive wastewater sample for measles virus, which marks the first wastewater detection of the virus in the state. The sample was collected Aug. 11, 2025, at a site in West Hawai‘i County, and DOH was notified of the result on Aug. 26, 2025. No suspected measles cases have been reported as of Aug. 27, 2025.

Wastewater sampling is routinely conducted across Hawai‘i as part of infectious disease surveillance. It can detect viral genetic material shed by infected individuals, even if they are not showing symptoms or have not reported illness. Testing for measles virus was added to surveillance in 2025, through WastewaterSCAN in May, NWSS-Verily in July, and Biobot Analytics in August.

“The recent detection of measles virus in our wastewater is a reminder that this disease is still a threat,” said Gov. Josh Green, MD. “Vaccination remains our strongest defense to stop measles before it spreads in Hawai‘i. Let’s work together to protect each other and keep our islands safe and healthy.”

The presence of measles virus in wastewater does not confirm a clinical case or community spread. Instead, it signals DOH to be alert and prepared for possible measles cases. The two confirmed measles cases in Hawai‘i in April 2025 occurred before measles wastewater testing began and are not related to this current wastewater detection.

DOH urges everyone to stay up to date on the measles, mumps, and rubella (MMR) vaccine. Measles is highly contagious but preventable through vaccination, according to the DOH.

“Infants under 1 year of age are at particularly high risk because they are too young to be vaccinated, but in certain situations, vaccination may be recommended for children between 6 and 12 months if they are exposed to a known case,” the DOH reports. To get MMR vaccine, contact your medical provider or pharmacy.

The DOH advises, if you traveled to an area with a current measles outbreak, speak with your doctor if you develop symptoms. International and US outbreaks continue to rise, with 42 states reporting cases as of Aug. 26, 2025. DOH will issue a medical advisory to healthcare providers statewide with information on how to test for measles and current vaccination recommendations.

Measles symptoms usually start with a high fever, cough, runny nose, and red eyes, followed by a rash of tiny red spots that begins at the head and spreads downward. The disease can lead to serious complications, including pneumonia, neurological illness and death.

If you think you have symptoms of measles or were exposed to someone with measles, isolate immediately and contact your healthcare provider for guidance to avoid further spread.

For more information about measles, visit:

• DOH measles information website
• CDC measles website
• MMR vaccine factsheet