A male adult film star in California who underwent regular HIV testing still ended up contracting the virus and infecting two other men before the disease was detected, according to a new report of the case.

The case underscores the need for adult film workers, and others at risk for HIV infection, to take multiple precautions to prevent HIV transmission, the researchers said. HIV testing cannot detect the virus in very early stages of infection, leaving a window when a person can unknowingly transmit the virus to others.

"Adult film performers and production companies, medical providers and all persons at risk for HIV should be aware that testing alone is not sufficient to prevent HIV transmission," the researchers said.

In the new case, a period of 22 days elapsed between the adult film star's last negative HIV test and his positive HIV test. During that time, the man (referred to as "patient A") had sex with 12 other adult film workers, and three nonwork partners, without using a condom. Of these contacts, one adult film worker and one nonwork partner both tested positive for HIV less than a month after their sexual contact with patient A.

All three men had a genetically similar strain of HIV, suggesting that patient A transmitted the virus to the other two men, the report said. [7 Devastating Infectious Diseases]

The researchers note that the production companies that hired patient A directed him to have sex without a condom. Since employers are required by law to ensure a safe working environment, the adult film industry should consider using multiple strategies to prevent HIV transmission, including use of condoms, regular HIV testing and use of antiviral drugs, even for people who don't have HIV. (Some antiviral drugs are now approved for use by people who don't have HIV but are at high risk for infection, a treatment known as "pre-exposure prophylaxis" or PrEP.)

"Combined with condoms, PrEP remains an important approach for preventing HIV infection among persons at high risk for HIV infection, including adult film industry performers," the researchers said.

The report, from researchers at the California Department of Public Health and the Centers for Disease Control and Prevention, is published today (Feb. 11) in the CDC journal Morbidity and Mortality Weekly Report.

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