News Archive

Group B Meningoccal Bacteria Identified (June 2010)

The Larimer County Department of Health and Environment has received lab results from the U.S. Centers for Disease Control and Prevention (CDC) which showed that a Fort Collins man who had symptoms of meningococcal meningitis, but who had no confirming lab findings in hospital and commercial lab tests, actually had Group B meningococcal disease.

This strain is different from the Group C meningococcal outbreak involving the recent cases in three Fort Collins hockey players and a CSU student who became ill on Memorial Day weekend. It is believed to be a sporadic case; these occur one to three times per year on average in Larimer County.

The man with Group B meningitis (known as "Patient 4") was admitted to the hospital on June 14, the same day as two of the hockey players, but was treated and released from the hospital three days later and is doing well. This is not a new case.

"It was originally thought this person might have a viral strain of meningitis, since all of his cultures were negative," said Dr. Adrienne LeBailly, director of the Health Department.

"Since then, further testing -- done by the CDC to assess any connection to the outbreak -- found DNA evidence of Group B meningococcal bacteria. Though all five cases of illness were caused by meningococcal bacteria, the Group B strain is unrelated to the other four cases we've seen in Larimer County," said LeBailly.

Because he had clinical symptoms of meningitis, his close contacts were treated with antibiotics soon after he became ill.

"Group B meningococcal bacteria are not covered by the meningococcal vaccine. The vaccine protects against the A, C, Y, and W-135 groups. The bacterial group of a meningococcal infection cannot be distinguished by clinical symptoms; only lab testing can identify it.

The Health Department reports no further cases of meningococcal illness at this time. "This is a good thing," said LeBailly. "It means the quick treatment of close contacts has helped to prevent further spread."

The last meningocococal cases in Fort Collins were admitted to the hospital on June 14. A case related to the hockey game in Fort Collins was admitted to a hospital in Montana on June 17. Because the incubation period from exposure to illness is generally two to 10 days, the further one gets from the last exposure, the less the risk of additional cases.