Health officials confirmed Saturday the first case of measles in Long Beach in four years and warned Long Beach residents to make sure they’re up-to-date on their measles vaccination.

Officials said an adult, who is now recovering at home, didn’t know they were infected with the virus as they went about their business in Long Beach this week, visiting restaurants, movie theaters and grocery stores. The virus spreads easily by air and direct contact with an infected person, according to Dr. Anissa Davis, city health officer.

“You are contagious four days before you actually come down with a rash,” Davis said. “A lot of times people are out and about before they come down with a rash.”

Measles is highly contagious and can be a severe disease that causes fever, rash, cough and red, watery eyes, officials said, and it spreads by air and direct contact with an infected person.

Cases have also been reported in other parts of Los Angeles County and in Orange County.

About 90% of people who have never had the measles vaccination become sick seven to 21 days after exposure.

Davis warned that people younger than age 5 or older than age 20 are at higher risk for complications that can include pneumonia, ear infections, brain swelling and in rare cases, death.

Officials say people who visited the same locations in Long Beach around the same time as the infected individual may have been exposed to measles by sharing the same air space. If anyone was at the following locations at the days and times specified should monitor for symptoms of measles for 21 days.

Date and Time Location Address April 28 from 5:30 to 7 p.m. Pizzanista 1837 E 7th St, Long Beach 90813 April 28 from 6 to 7:30 p.m. Total Wine 7400 Carson St., Long Beach, 90808 April 30 from 5 to 7 p.m. Susan European Dressmaker 3319 E 7th St, Long Beach, 90804 May 1 from 8 to 10 p.m. Art du Vin Wine Bar 2027 E 4th St, Long Beach, 90814 May 1 from 2 to 5 p.m. Ralphs 2930 E 4th St, Long Beach, 90814 May 2 from 3 to 6:30 p.m. Ralphs 6290 PCH, Long Beach, 90803 May 2 from 6 to 10 p.m. AMC Marina Pacifica 6346 E PCH, Long Beach, 90803 May 3 from 11 a.m. to 1 p.m. Broadway Carwash 4000 E Broadway, Long Beach, 90803

The person also visited multiple locations in Orange County and in L.A. County outside of Long Beach.

“Those who think they may have measles should call their medical provider before arriving at the medical office to avoid exposing others to the virus,” officials said in a release.

“This is a preventable disease with a vaccination,” Davis said. If you’re unsure if you’ve been vaccinated, see your doctor, she said.