Nassau County health officials issued a public warning after two confirmed of measles were confirmed within days — and diners at a popular restaurant may have been exposed.

The first case involved an unvaccinated child under the age of 5, who was Nassau’s first confirmed case since 2024.

Officials then issued a public health alert after a New York City resident who came down with the deadly illness potentially exposed diners at ritzy Italian eatery 388 in Roslyn Heights on May 3.

“The Nassau County Department of Health is closely investigating the case, including any potential exposures, and taking the necessary steps to prevent the spread of measles,” said Nassau County Commissioner of Health Dr. Irina Gelman.

“Measles can cause serious illness, with complications that may include pneumonia, encephalitis, and often results in hospitalization and sometimes death,” she added, urging residents and parents of young children to get vaccinated.

Gelman said anyone who ate at 388, an upscale Italian restaurant in Roslyn Heights, on May 3 between 7:15 p.m. and 10:30 p.m. — may have been exposed to the virus.

Nassau’s first confirmed case came just days earlier, when a child, identified only as under age 5, was not vaccinated, the county Department of Health said.

The last confirmed measles case in Nassau County was in March 2024, while neighboring Suffolk County reported its most recent case in March 2025.

At least 10 cases of measles have been reported statewide so far in 2026, according to the New York State Department of Health.

It was unclear Sunday whether that figure included the Nassau cases.

Last year, there were 20 confirmed cases in New York City and 28 in New York State for a total of 48 cases, according to state health data.

Nationwide, childhood measles vaccination rates have dropped below the 95% threshold needed to prevent outbreaks, according to the Associated Press.

In 2025, just 82% of Nassau children between 24 and 35 months had received their first measles, with Suffolk sitting at roughly the same, according to state health data.