Truvada combines two drugs that have been part of the anti-retroviral cocktail taken by HIV-positive patients for years.
In addition to suppressing HIV that is already in the body, the pill can reduce the risk of new infections by as much as 92%, according to the U.S. Centers for Disease Control and Prevention. The prevention method is known as pre-exposure prophylaxis, or PrEP.
"PrEP is not a silver bullet, it's not a panacea, but it is another tool that we need to offer our county residents who are at high risk of contracting HIV," Kuehl said.
Officials said nearly 60,000 people are living with HIV in the county, and about 1,850 more become infected each year. Many of them are low-income gay and bisexual men of color.
The supervisors directed the public health department to come back in 30 days with a plan to reach out to high-risk populations and disseminate the drug.
Most HIV prevention advocates who spoke Tuesday praised the move and said they wanted to see the treatment more widely used.
But Truvada also has its opponents. The highest-profile critic has been AIDS Healthcare Foundation President Michael Weinstein, who launched a campaign against the prevention strategy, saying many users would not take the drug consistently enough to stave off infections and might give up other protections like condoms.
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For the record