Administrators at the College, Harvard University Health Services, and Cambridge Public Health Department are working to contain the spread of mumps and care for students who have been affected by the virus by relocating them to isolated housing for an extended period of time.

“We have officially an outbreak of mumps in this population,” HUHS Director Paul J. Barreira said. “It’s happening with students who are well-immunized, so it’s a breakthrough infection. So the task is to get the population to act in ways that minimizes the spread of the virus.”

The number of confirmed cases at the University has not increased since Barreira’s email last Wednesday, which stated that six students on campus had contracted the virus. Since that time, Barreira has circulated information about preventing the spread of the virus, and encouraged students exhibiting symptoms of mumps to contact HUHS.

“We have no way of knowing how it came on campus,” Barreira said. “Public Health is responsible with interviewing everybody, and then they try to do a contact mapping to see if they can identify how it came to campus, but at this point they’re not optimistic they will find what’s called the index case.”

Barreira said preventive measures against mumps include practicing hygienic habits like hand washing and refraining from sharing eating utensils, seeing a doctor at the onset of mumps-like symptoms, and isolating suspected cases early.

“We examine and identify clinically people who are at risk, do a buccal swab to check for virus, then we communicate to the College,” Barreira said. “Then the College notifies the House and then identifies the room that they’re going to move into.”

The Cambridge Public Health Department mandates that students infected with mumps be quarantined in a single room with an individual bathroom for five days. Since most dorm rooms share a bathroom, students are housed elsewhere on campus, according to Barreira.

In an emailed statement, College Spokesperson Rachael Dane said the College is “utilizing various locations on campus for students who need to self-isolate, including rooms in some of the Houses and Harvard-owned properties.”

“We are also taking special precautions with regards to cleaning these spaces, with Facilities Maintenance Operations custodians undergoing special training cleaning the rooms and disposing of waste,” Dane wrote.

Ninety-nine percent of undergraduates have been vaccinated against mumps, according to Barreira. Barreira added that although some other universities verify mumps immunizations through a questionnaire, Harvard requires documentation of the vaccine.

“In this state, we require two shots, one month apart,” Barreira said. “We often test to see if there’s adequate antibodies too. In some states around the country, they only require one shot, which by [Centers for Disease Control and Prevention] standards is considered under-immunization.”

Though some Harvard affiliates have asked whether a third booster shot for all students would help prevent the spread of the virus, Barreira said there is no evidence that a third booster shot would provide more immunity.

“The CDC is very clear in their recommendations that a third shot doesn’t provide more immunity,” Barreira said. “So if you’ve been well vaccinated, there’s no indication that a third shot will give you any more protection.”

As undergraduates prepare for spring break, University administrators will send “a message encouraging responsible behavior when traveling with respect to careful hygiene and not using public transportation if ill,” Barreira wrote in an email.

In the meantime, administrators are informing parents of students about the recent mumps outbreak. On Wednesday, Dean of the College Rakesh Khurana sent an email to Harvard parents looping them into Barreira’s latest email about the virus.