Princeton University has started offering a meningitis vaccine, yet to be approved in the U.S., to its more than 5,000 undergraduate and graduate students this week. By Monday evening, the first day of the vaccination effort, at least 1,200 were vaccinated in the main student center.

"They're getting people in and out of there very quickly, but it feels like everybody in the university is in that building right now," said Jonathan Frankle, a senior, after leaving the building Monday afternoon.

The federal Food and Drug Administration granted the university special permission to use the vaccine, which has been approved in Europe and Australia but not yet in the U.S., in response to a campus outbreak of a meningococcus B strain of the bacterial infection. The vaccine commonly used in the U.S.  does not protect against that strain. The new vaccine, Bexsero, is manufactured by drugmaker Novartis.

Dr. Thomas Clark, who oversees the meningitis division of the U.S. Centers for Disease Control and Prevention, has been on campus since Thursday, responding to questions from students and faculty. He said he hopes the vaccine effort will help curb the problem at Princeton.

"We think vaccination will protect students and protect additional students," Clark said.

Meningitis B is a bacterial infection, transmitted through close contact such as kissing, and is sometimes life threatening. Since March, Princeton has identified eight cases. That includes a friend of Julia Stoner, a Princeton senior studying civil and environmental engineering.

"That scare alone was enough to warrant our consideration of the vaccine," said Stoner, on her way to class. Stoner said the campus has been abuzz about meningitis, with mass emails and fliers informing students about the situation.

"I think it's something people are slipping into conversation," said Stoner, who plans to get vaccinated later in the week. "When it comes to sharing things, people have been more conscientious about saying, 'Oh no, let me get another spoon or straw,' a little bit in a joking way to make light of it, but people are taking it more seriously."

Conversations about importing the vaccine, meanwhile, started this summer, according to Clark. He said the shot has proved safe, noting its previous use to inoculate hundreds of thousands of kids in New Zealand.

"This is just like any other shot. You may get a sore arm for a couple days, and then you're fine," said Clark, adding that anyone who thinks they may have experienced an adverse event should report it.

For Frankel, who thinks the whole situation has been overblown both on and off campus, getting vaccinated was still an easy decision.

"I'd rather have a sore shoulder than not have a shoulder at all," said Frankle. "I don't want to get meningitis."

The campus is offering the vaccine through Wednesday, but students will need to return for a booster shot in about three months.