HARRISBURG, Pa. - The Pennsylvania Department of Health is warning the public about potential exposure to a case of measles in the Philadelphia area.

As CBS Philly reported, a person believed to have the measles may have exposed others to the illness at two locations: a CVS pharmacy in Wayne, Pennsylvania, on Dec. 28, and the Please Touch Museum in Philadelphia on Dec. 29.

Measles is a highly contagious virus that can spread through coughing or sneezing. Infected droplets may remain contagious on surfaces for several hours.

Get Breaking News Delivered to Your Inbox

Symptoms appear one to two weeks after exposure and may include runny nose, watery eyes, cough and a high fever. After four days, a telltale raised, red rash starts to spread on the face and down the body. The rash usually lasts four to seven days.

Complications from measles can include ear infection, diarrhea and pneumonia, and in severe cases inflammation of the brain and even death. Measles can also cause miscarriages or premature delivery in pregnant women.

Health officials say the vaccine for measles is highly effective. However, the following groups of people are at risk if they had contact with someone who's infected:

Infants less than one year of age who are too young to have received the measles, mumps and rubella (MMR) vaccine.

Individuals who were vaccinated with an inactivated vaccine, which was used from 1963 through 1967, and have not been revaccinated.

Individuals born after 1957 who have only received one dose of MMR vaccine.

Individuals who refused vaccination.

Individuals from parts of the world where there is low vaccination coverage or circulating measles.

The MMR vaccine can help prevent infection if it is given within three days of exposure. If it has been more than three days since exposure, a dose of immune globulin can provide protection up to six days after exposure, officials say. They add that there is no risk in getting an additional dose of the MMR vaccine.

A resurgence in cases of measles sickened hundreds of people across the U.S. in recent months. Outbreaks in Southern California, Ohio, and New York were among the worst in decades.

The Centers for Disease Control and Prevention said many cases could be traced back to people avoiding the vaccine for "philosophical" reasons, or because they had heard claims -- which have since been discredited -- linking vaccines and autism.