No. 2: Trader Joe's
A Trader Joe's store Creative Common

Health officials say two people contracted measles in Framingham, Mass. -- and one of them had been to a Trader Joe’s near the time of the outbreak.

This sparked a swift reaction from the Massachusetts Department of Public Health, which announced on Monday that one of the patients had stopped by a local restaurant and a Trader Joe’s location on Feb. 15 or Feb. 16. The state is asking any customers who may have been exposed to the virus on those dates at those locations to come to vaccination clinics.

A manager at the location said that everything was fine at the store but could not comment further. He referred IBTimes to the Trader Joe’s corporate representative who was not immediately available for comment.

“We went to Trader Joe’s, and we held clinics on the 22nd and 24th," said Steven Ward, director of public health in the town of Framingham, to "We’ve educated the employees, and we believe most of the employees have received their vaccinations." He also reported that the measles patient also spent time at a restaurant called Samba’s, where another clinic was set up.

Ward told CBS local that a second infected person was a resident of Spencer, a town located approximately 35 miles away, and that person works at the Bose Corp. headquarters in Framingham.

Though most Americans aren’t at risk for measles, the respiratory virus is highly contagious. But symptoms typically don’t begin until 10 days after their initial infection.

“Once it’s exhaled, the measles virus can remain suspended in the air for up to two hours,” said Dr. Deborah Yokoe, medical director for infection control at Brigham and Women’s hospital in Boston, in an email to the Boston Globe.

“Beyond that two-hour period, there is no remaining risk, and there are no steps that need to be taken to clean the environment,” she said.

The disease seems similar to a cold at first. Patients develop a cough, fever, runny nose and red eyes, but this can escalate into other problems such as pneumonia, ear infections and even brain swelling in some people.

Measles have largely not been a concern in the United States for decades, since most children have been receiving measles-mumps-rubella (MMR) vaccinations. Or, if they were born before 1957, they have developed immunity over their lifetime.

There has been a recent trend among some people to not vaccinate their children for fear of other health risks.

There are usually less than 60 cases per year in the United States, but in 2013 there were more than 175, according to the Centers for Disease Control and Prevention.

Earlier this month, health officials in Contra Costa County, just outside San Francisco, warned that thousands of residents may have been exposed to the virus after a young man in his 20s rode public transit after contracting measles while traveling in Asia, according to NBC.