SAN FRANCISCO (AP) -- Federal officials on Wednesday blamed unsafe working conditions and poor training for the death of a young Veterans Affairs medical center researcher in San Francisco who died after handling bacteria that causes meningitis.

The federal Occupational Safety and Health Administration found three serious violations at the lab that exposed Richard Din, 25, to the bacteria and led to his death on the way to the hospital April 28.

In particular, OSHA chided the lab for allowing Din to work with the bacteria in the open rather than in a so-called biosafety cabinet, which isolates germs behind a protective screen and provides ventilation.

"Richard Din died because the VA failed to supervise and protect these workers adequately," said Ken Atha, OSHA's regional administrator in San Francisco. "Research hospitals and medical centers have the responsibility as employers to protect workers from exposure to recognized on-the-job hazards such as this."

OSHA also said that lab workers, including Din, should have received meningitis vaccines and training on recognizing symptoms of the disease. Din wasn't vaccinated and complained of headache, fever and chills after he left work on a Friday but did not seek medical help until his condition worsened the next day.

VA spokeswoman Kellie Mendonca said the lab has been closed since Din's death and "no further work with viable bacteria has been allowed." Mendonca said the medical center adopted all of OSHA orders before it received notice of the violations. She also said that Din was working with a vaccine-resistant strain of the bacterium.

OSHA spokeswoman Deanne Amaden said "the serious violation is because the VA did not provide vaccines to workers for other strains where there are vaccines available -- based on the work they were doing."

OSHA's notice of violations requires the VA to vaccinate its lab workers against any dangerous germs they are working with, provide better training to recognize symptoms of illness, and mandate that work with disease be conducted in safety cabinets.

OSHA can't fine other federal agencies as it can private companies.

Meanwhile, a vaccine for the meningitis strain that killed Din may soon be available in the United States. Novartis AG won approval to sell its vaccine in Europe this year while it's negotiating with U.S. regulators to do the same here. Other companies are also developing vaccines.

A 2005 paper published in the Journal of Clinical Microbiology - the most recent study of its kind -- said 16 cases of probable laboratory-acquired meningitis occurred worldwide between 1985 and 2001, and eight were fatal.

Bacterial meningitis causes an estimated 170,000 deaths worldwide each year, according to the World Health Organization.

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