Delaware health officials warn residents of possible measles exposure in Rehoboth Beach, Sussex County

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Delaware health officials are sounding the alarm after an out-of-state visitor with measles spent time in Sussex County earlier this month.

The state’s Division of Public Health was notified that the individual visited an unknown number of stores and restaurants in the greater Rehoboth Beach area Sept. 4. Officials said the person was not showing symptoms at the time but was believed to be contagious.

Because the state could not confirm all the locations the person visited, the Division of Public Health issued a community-wide notification Wednesday.

The news comes as Delaware is experiencing a measles outbreak. Currently, 23 cases have all been confirmed in Kent County. Before the recent surge, the state had not reported a measles case in more than a decade.

Officials recommend that people who were in the area Sept. 4 monitor themselves for early symptoms of measles. Symptoms include fever, cough, runny nose and pink eye lasting up to four days before a rash appears. The rash, a telltale sign of infection, typically appears three to five days after symptoms begin, starting on the face before spreading down the body.

Unvaccinated, pregnant, immunocompromised persons and children who are too young to be vaccinated are at higher risk of contracting and spreading the infectious disease.

People who develop these symptoms should immediately self-isolate and contact a health care provider to report their symptoms. If symptoms are severe, they should seek immediate medical care. Health officials said that people who suspect they have been infected should call ahead before visiting a health care facility so staff can prepare for their arrival.

Health officials encourage eligible residents to get vaccinated to protect themselves from contracting measles. Receiving two doses of the measles, mumps and rubella vaccine is 97% effective in preventing contraction and is the best form of protection, according to officials.

Residents can confirm whether they have been vaccinated against measles by confirming with their doctor or through the DelVAX Public Portal. Vaccinations are available at health care offices as well as the state’s public health clinics and mobile health units.

The U.S. is experiencing its largest measles outbreak since 1991. Cases surpassed 2025 totals in July. More than 3,300 cases have been reported so far in 46 states, with Pennsylvania leading the nation with 676 individual cases reported. The 23 cases in Kent County have been the only confirmed cases in Delaware so far.