State health officials are encouraging the Maui County residents to stay up to date on the measles vaccine after detecting the virus in wastewater at two sites on Maui.

The state Department of Health said the detections were the first ever in Maui County. The wastewater samples were collected Nov. 18. No suspected measles cases have been identified on Maui.

The first positive wastewater detection of measles occurred in October on Kauai Island, though no suspected measles cases were identified on the island, according to the department.

Wastewater sampling is routinely conducted across Hawaii to detect viruses, even if the infected individuals are not showing symptoms.

Measles is highly contagious but preventable through vaccination. The vaccine is combined in an MMR shot that also treats mumps and rubella. Two doses are recommended for protection.

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 department warns the disease can lead to serious complications, including pneumonia, neurological illness and death.

Earlier this year, Gov. Josh Green, who has worked as a medical physician, said measles is one of the most contagious known viruses.

“There’s no need to panic — but there is a need to act,” Green said. “We’ve already seen what happens when vaccination rates drop: more cases, more outbreaks, more lives at risk. The best thing you can do to protect your family, your community and our keiki is to get vaccinated.”

The Green administration noted that in 2025, more than 600 cases have been reported across 22 states. Globally, cases have surged with the World Health Organization estimating 10.3 million cases in 2023.

“Our goal is to prevent cases from becoming outbreaks,” said Dr. Kenneth Fink, director of the Hawaii Department of Health. “The best way to prevent an outbreak is to have at least a 95% community vaccination rate.”

Statewide, Hawaii’s MMR vaccination rate stands at 89.8%.

The health department said infants younger than 1 year old are at a particularly high risk because they are too young to be vaccinated, except in certain situations.

The department is advising anyone who’s traveled to an area with a current measles outbreak to speak with their doctor if they develop symptoms.

International and U.S. locations are still experiencing cases of measles, with 43 jurisdictions reporting 1,753 confirmed cases as of Nov. 18. A total of 23 measles cases were reported among international visitors to the U.S.