SAN FRANCISCO (CBS SF)– A San Francisco firefighter has filed a legal claim alleging that colleagues and managers harassed and discriminated against him after learning he had tested positive for HIV.

The San Francisco Examiner reported Monday that 40-year-old Stephen Kloster filed a claim with city officials last Tuesday.

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If the city denies the claim, Kloster can file a lawsuit.

Kloster says he doesn’t know how he contracted HIV.

He claims he may have contracted it after an exposure while working on ambulance duty in 2003. During a call, he was splashed with blood while treating a patient.

The Examiner reported Kloster fell ill after five years on the department and that he lost 100 pounds. Tests revealed he was HIV positive, but by 2007, a year after his diagnosis, his T-cell count improved and he was able to return to duty.

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The newspaper quotes Kloster as saying that upon his return to duty, word had spread about his condition. He says colleagues at the firehouse, Station 19, near Stonestown Galleria, wouldn’t let him cook and they’d make jokes that he was gay and that his girlfriend was a man.

In addition, Kloster claims his superiors threatened him and at one point, he told the paper, they had laid hands on him.

The report says Kloster cannot explain why he is no longer on duty and has not been reassigned since taking a vacation last year. A fire department spokeswoman confirmed Kloster was still an employee and that the department has not discriminated against him.

The newspaper reported that the city’s human resources department declared in 2012 his illness was work-related. The city attorney’s office and fire department declined comment.

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