SAN FRANCISCO (AP) -- California health officials are investigating the death of a researcher at a Veteran's Affairs infectious diseases lab that may have been caused by a rare strain of bacteria.

The 25-year-old man, who has not been named, died over the weekend shortly after asking friends to take him to a hospital, the San Jose Mercury News reported ( http://bit.ly/IAQYAt) Wednesday.

California Occupational Safety and Health Administration spokesman Peter Melton told the newspaper that the man had been handling bacteria at the VA Hospital's Northern California Institute for Research and Education. The bacteria can cause life-threatening meningitis and blood infections.

Cal-OSHA was investigating the death and trying to determine if the lab followed safety protocol.

The chief of the VA Hospital's infectious diseases division, Harry Lampiris, said workers at the facility are expected to wear gloves, gowns and do their work behind a protective "safety cabinet," or hood, while isolating the bacteria.

"His co-workers felt he was highly competent and that he was adequately supervised to do the level of work," Lampiris said.

The researcher was working with others in the lab on developing a vaccine for a rare strain of the Neisseria meningitidis bacterium. It can cause meningitis, an inflammation of the lining of the spinal cord or brain, or get into the bloodstream where it causes a severe infection called sepsis.

The cause of the man's death is believed to be a blood infection.

The germ can spread through close contact. The San Francisco Department of Public Health was trying to locate everyone who was in touch with the researcher while he was infected, said spokeswoman Eileen Shields.

Friends and people who worked with the man, as well as about 60 health workers involved in his treatment, were being given antibiotics, Shields said.

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