NEW CITY, N.Y. (CBSNewYork) — Rockland County officials fear residents in New York and New Jersey may have been exposed to the measles this month.

According to a release from County Executive Ed Day and County Health Commissioner Dr. Patricia Schnabel Ruppert, an international traveler was found to be carrying the disease and visited several locations in Rockland, Westchester, and Bergen counties.

“We are working diligently to monitor the situation and protect the community from measles. We will keep residents informed of any updates,” Dr. Ruppert said Sunday.

MORE: NY, NJ Officials Warn Of Potential Measles Exposure At Newark Liberty International Airport, Rockland County

Residents are being warning they may have been infected by the unidentified traveler at some point between Oct. 4 and Oct. 11.

Health officials say anyone at these locations may have been exposed to the measles:

Congregation Bais Elazer in Monsey, N.Y. on Oct. 4

Mia’s Reflexology in New City, N.Y. on Oct. 4

Lifetime Gym in Montvale, N.J. on Oct. 5

Wesley Kosher in Monsey N.Y. on Oct. 5

Congregation Borov in Monsey, N.Y. on Oct. 5 and Oct. 6

Costco in Nanuet, N.Y. on Oct. 7

Care 365 in Monsey, N.Y. on Oct. 8

Westchester Medical Center’s Emergency Room in Valhalla, N.Y. on Oct. 11

Lifetime alerted gym members Saturday with an email, saying a man with measles worked out there on Oct. 5 between 8:30 a.m. and noon, CBS2’s Lisa Rozner reported.

“I just can’t believe it. I mean, I wasn’t even aware of it,” Rutherford resident Linda Sabino said.

Symptoms of the measles include fever, runny nose, red eyes that are sensitive to light, coughing and a red rash. The illness usually appears 10-12 days after exposure, but can sometimes take up to three weeks to develop.

Health officials said if you have had two doses of measles mumps rubella vaccine then you are considered immune to the disease. Dr. Rebecca Varghese of Lifeline Urgent Care recommends getting them if you haven’t.

“Even adults can be vaccinated. They have to take two doses of MMR vaccine, which is about 28 days apart so that will prevent them from having the disease,” Varghese said.