State health officials are investigating a puzzling outbreak of mumps in Latino communities in Boston, Chelsea, and Revere, and have advised health care providers to be alert for additional cases.
The state Department of Public Health has recorded 12 mumps cases since the end of March.
Previously in Massachusetts, mumps has been found chiefly among vaccinated college students and others connected to colleges and universities. But the dozen new cases involve people aged 20 to 41 with no known links to higher education.
“What’s new here is that we’re seeing mumps in the community, not in the environment of colleges and university,” said Dr. Alfred DeMaria, the state epidemiologist.
When mumps occurs on college campuses, it is more likely to be diagnosed, because students go to the same health center. In the community, DeMaria said, cases may go unrecognized.
Although most people recover fully from mumps, sometimes the illness can have serious complications if the virus infects ovaries, testes, pancreas, or the lining of the spinal cord. Health officials are hoping to prevent further spread by identifying and isolating any new cases. Doctors are being urged to suspect mumps if they see a patient with symptoms such as swollen salivary glands, DeMaria said.
“Most times, with swollen glands, it’s not mumps,” he said. “Unless they’re aware we’re on the lookout, they’re not thinking mumps.”
The 12 people, who fell ill between March 24 and May 31, are Colombian, Dominican, Guatemalan, and Salvadoran immigrants — but they most likely caught the mumps in the United States. None is known to have traveled to another country before becoming ill. Officials believe most were not vaccinated against mumps, but don’t yet know whether they had contact with each other.
Health officials have instructed the patients with mumps to stay home and avoid close contact with others for five days after first feeling sick.
It may never be known exactly where this outbreak originated, DeMaria said. Mumps is difficult to track because people can transmit it before symptoms emerge. Sometimes people get infected but don’t feel sick, and spread the virus without knowing it.
Mumps is spread when an infected person coughs or sneezes and sends droplets into the air, or when people share utensils or water bottles. Symptoms start 12 to 25 days after infection, typically swelling of the salivary glands, as well as muscle aches, loss of appetite, headache, and low-grade fever.
For additional information, contact the health department at 617-983-6800 or visit http://www.mass.gov/eohhs/gov/departments/dph/programs/id/epidemiology/factsheets.html