The public is being warned about possible exposure to measles at several stores in Chester County, Pennsylvania.

WEST GROVE, Pa. (WPVI) — The Chester County Health Department is warning the public of possible exposure to measles at several local stores.

The possible exposure occurred on Sunday, October 4 at the following locations:

-CVS at 870 Baltimore Pike, Kennett Square, 19348; between 10:45 a.m. and 3 p.m.

-CVS at 857 West Baltimore Pike, West Grove, 19390; between 12:30 p.m. and 3:30 p.m.

-Giant at 849 Baltimore Pike, West Grove, 19390; between 1 p.m. and 3:45 p.m.

A person infected with measles visited these locations while contagious, county health officials said.

RELATED: Measles cases surpass 1,000 in Pennsylvania, amid state’s largest outbreak in decades

Anyone in these places is asked to check if they are immunized against measles.

The Department of Health has stated that you are considered immune to measles if any of the following conditions apply to you:

-Born before 1957, or

-Have ever had measles, or

-Have received at least one of two doses of measles vaccine (usually administered as the measles, mumps and rubella (MMR) vaccine).

People who are not protected against measles can contract the virus up to two hours after a person with measles leaves the same room or airspace, health officials said.

This incident comes amid a historic measles outbreak in Pennsylvania, with more than 1,000 cases reported.

For more information, visit Chesco.org/Measles.