Increased Estimates of HIV Incidence in the U.S.

To plan and evaluate HIV prevention efforts, authorities need to know the incidence of infection. The CDC, using back calculation based on AIDS case reporting, previously estimated that 40,000 new HIV infections occurred in the U.S. in 2006. With progression to AIDS delayed by antiretroviral therapy, however, this method no longer provides accurate estimates. Now, using a new serologic assay that can distinguish between recent and long-standing HIV infection, researchers have re-estimated HIV incidence in the U.S. for 2006. They corroborated this estimate with an extended back-calculation approach that incorporated HIV diagnoses reported from 40 states.

The researchers tested remnant serum samples for 6864 patients who were diagnosed with HI…