By Amy Norton
TUESDAY, Nov. 26, 2013 (HealthDay News) -- A potentially deadly form of meningitis has now been reported at three U.S. colleges, and experts say that while it's not time to panic, students need to be aware of the possible symptoms and seek treatment for them right away.
This outbreak is concerning because most of the cases have been confirmed as a subtype of bacterial meningitis called group B. And the current meningitis vaccine used in the United States does not protect against group B.
Meningitis is an inflammation of the membranes that surround the brain and spinal cord, and it's most often caused by a virus.
Bacterial meningitis is rare in the United States, but when it strikes, it's usually severe. About 10 to 15 percent of Americans who fall ill with the infection die, and up to 19 percent of survivors suffer nervous-system damage or lose a limb, according to the U.S. Centers for Disease Control and Prevention.
Cases have fallen in recent years, thanks to vaccination. Last year, the CDC says, there were about 500 infections, of which 160 were group B.
But as of Friday, eight cases of group B meningitis had been reported at Princeton University in New Jersey, where an outbreak began last March.
Last week, the University of California, Santa Barbara said three students had fallen ill with confirmed cases of group B. Another New Jersey college -- Monmouth University in West Long Branch -- said an employee had been hospitalized with meningitis.
It was not yet known whether the Monmouth case was group B or not.
No one is sure why most of the outbreak cases have been B strain, said Dr. William Schaffner, an infectious disease expert at Vanderbilt University School of Medicine in Nashville, Tenn.
In the United States, group B meningitis mainly strikes infants, not college-age adults -- who most often contract other bacterial types. "This is very unusual," Schaffner said. "We're all kind of scratching our heads at this point."
What is clear, he said, is that young people should still get the standard U.S. vaccine that protects against four other types of bacterial meningitis (known as A, C, Y and W). Besides meningitis, those bacteria can also cause serious bloodstream infections.
Ideally, children should get the vaccine when they are 11 or 12 years old, then have a booster shot at age 16. "But it's never too late to get it," Schaffner stressed.
Just as important, he said, is awareness of the initial symptoms of bacterial meningitis. Those include sudden fever, headache, neck stiffness, vomiting and sensitivity to light.
Schaffner said Vanderbilt has sent information to students urging them to get quick medical attention if they develop those symptoms. "Get to the student health center," Schaffner said. "Don't try to tough it out."
One advocate who's had personal experience with meningitis agreed.
"It is really important for everyone to be aware of the symptoms," said Lynn Bozof, of the National Meningitis Association, an advocacy group founded by parents of children killed or disabled by meningitis.
A vaccine -- called Bexsero -- does protect against group B meningitis, but it is not yet licensed in the United States.
Bexsero is licensed in Europe and Australia, however, and Princeton announced last week that it is importing the vaccine -- with approval from the CDC and U.S. Food and Drug Administration. It will be offered to students and certain employees who may be at increased risk.
In general, college students living in dorms are at risk of meningitis because they are in close contact. But the CDC and other experts have stressed that bacterial meningitis is not passed casually, like the common cold. People have to come in contact with someone else's respiratory secretions -- through kissing, or sharing food, drinks and utensils.
Bozof said it's not time for "panic." Still, she added, "if I were a student at Princeton, I would take this opportunity to get the [Bexsero] vaccine. I'd be the first in line."
For now, the vaccine is only an option for certain at-risk groups at Princeton, the CDC says. On Monday, the agency also said that Princeton students should feel free to stick to their Thanksgiving travel plans.