Fourteen percent of men and women living with HIV/AIDS were diagnosed with a new STI in a six month period. These rates of incident STI are similar to other community samples of people living with HIV/AIDS [28
]. Having been diagnosed with a recent STI was proportional for men and women and was not associated with income or receiving HIV treatments. Individuals who had been diagnosed with a co-occurring STI were only slightly younger, less educated, and were using more alcohol and other drugs. Recently contracting an STI was associated with poorer health including having a lower CD4 cell count, experiencing more HIV-related symptoms, and being less likely to have an undetectable viral load. STI co-infection was also associated with being unaware of one’s viral load, a potential indicator of poor engagement with health care. Together, these findings do not support the notion that improved health status accounts for increases in sexual risk behavior in people living with HIV/AIDS.
The association between believing that one is less infectious when their viral load is undetectable and being diagnosed with an STI was significant even after accounting for age, education, substance use, viral load and other health markers. These findings confirm previous research indicating that infectiousness beliefs play a central role in continued HIV transmission risks for some people living with HIV [1
]. The current study is the first we are aware of to report an association between infectiousness beliefs and STI co-infection, a circumstance that increases infectiousness regardless of blood serum viral load.
Having contracted an STI was not related to higher rates of unprotected sex. Indeed, greater rates of condom use with non-positive partners were observed among participants who had contracted an STI. This paradoxical finding is accounted for, however, by individuals who were diagnosed with an STI having a greater number of sex partners, including non-HIV positive sex partners. Partner selection strategies may therefore play an important role in contracting new STI among people with HIV. In particular, selecting same HIV status sex partners for unprotected sex (i.e., serosorting) does not protect against, and may even increase STI risks [7
]. In addition, the greatest rates of condom use with non-HIV positive partners were observed among participants who had been diagnosed with an STI and had a detectable viral load, again suggesting that people living with HIV take their viral load into account when making sexual decisions.
The current findings should be interpreted in light of their methodological limitations. Although statistically significant, some of the associations we observed were small in magnitude, such as the differences between STI groups on age and education. We used the more reliable and valid computerized interviews to collect sexual behaviors because it is less likely to induce socially desirable responding. Still our behavioral measures were self-reported and may nevertheless have been influenced by social desirability biases. The behavioral risks that we observed should therefore be considered lower-bound estimates of HIV transmission risks among people living with HIV/AIDS. In addition, we measured STI co-infection using self-reports which are also limited by socially desirable responding. Our community sample of people living with HIV/AIDS prohibited access to multiple clinics for medical records to confirm STI diagnoses. We also did not collect biological specimens for STI confirmation because point prevalence estimates do not confirm broader intervals of diagnoses. We were also unable to detect asymptomatic STI, again suggesting a lower bound estimate of STI. Our study was conducted with a convenience sample recruited in one city in the southeastern United States, limiting the generalizability of our findings to other populations in other regions. With these limitations in mind, we believe that the current findings have important implications for HIV prevention with people living with HIV/AIDS.
Research over the past decade shows believing a person with HIV is less infectious when told they have an undetectable viral load is associated with HIV transmission risk behaviors [30
]. Left unchecked, infectiousness beliefs can lead to increased risk behaviors, such as numbers of sex partners, and therefore exposure to STI, resulting in greater infectiousness than one could possibly know from their blood serum viral load. Fortunately, beliefs are amenable to interventions. Providing accurate information about the risks for STI and HIV transmission that is relevant to one’s relationships and life circumstances may be sufficient for reducing HIV transmission risks among some persons living with HIV/AIDS. However, others will require interventions that go beyond viral load education, understanding infectiousness, and the limitations of partner selection strategies. Interventions aimed at limiting numbers of sex partners and reducing unprotected sex typically require building new skills for sustaining long term behavior change [31
]. Interventions that include HIV status disclosure decision skills have been effective in reducing HIV risks in serodiscordant relationships and should be integrated in future interventions [32
]. Perhaps most essential to HIV prevention with people who have HIV/AIDS is the integration of STI diagnostic and treatment into routine clinical services. Patients should also be taught how to recognize early symptoms of STI and told they should seek health services if they suspect STI symptoms. Early detection and aggressive treatment of STI co-infections are necessary for reducing genital fluid infectiousness. Scaling up antiretroviral therapy for HIV prevention will therefore only be successful when infectiousness beliefs are reality-based and when co-occurring STI are prevented, rapidly detected and treated.