Florida HIV Incidence Estimate, 2007-2010

Background: Previously, prevalence data were used to estimate the number of new HIV cases; however, a new diagnosis does not constitute a new infection. In 2004, Florida initiated Incidence Surveillance in collaboration the Centers for Disease Control and Prevention (CDC). Data collection on HIV testing behavior, antiretroviral use and incidence testing (STARHS) results allows for a more accurate estimate of incidence. Incidence estimates permit public health officials to more precisely assess trends in HIV transmission and better appropriate resources.

Methods: The Stratified Extrapolation Approach, developed by the CDC, determines the probability that an individual would have an HIV test during his/her period of recent infection and assigns a weight to each case deemed recent (<5 months) or long-standing. Incidence is the sum of the weighted number of infections deemed recent. The incidence estimate for each demographic category was used to calculate incidence rates for 2007-2010.

Results: Comparing 2007 to 2010, there was a 29.5% decrease in incidence numbers; however, Florida still surpassed national rates in most demographic categories with few exceptions (blacks, Hispanics and persons aged 55 and over).  Incidence numbers for men who have sex with men (MSM) were higher than other transmission categories.  Rates among blacks remained higher than that of other ethnic groups.

Conclusions: From 2007-2010, Florida’s incidence rate remained higher than the national rate, but has decreased significantly while the national rate remained stable. Prevention efforts should be focused on black/African Americans, MSM and persons aged 13 to 34 years as their numbers remain unacceptably high.