In Puerto Rico, the urgency of HIV infection is visible in shear numbers: the rate of diagnosis is the fourth highest in all the United States at 33.8 per 100,000 of the population compared to a national average of 19.7. Even more concerning is the heightened risk for injection drug users of co-infection, infection of both HIV and Hepatitis C, where 42% of the country’s instances of HIV infection in men occur through injection drug use and an estimated 90% of people who use injection drugs (PWID) are infected with HCV.
To understand the social determinants of those who become co-infected with HIV/HCV, a team of UNL-affiliated researchers—including REACH Lab’s Bilal Khan and Kirk Dombrowski—ran an extensive study in four rural Puerto Rican towns of 315 injection drug users. Their findings were recently published in Addictive Behaviors Reports, providing insight into the differences in age, number of years injecting, sexual identity, and access to healthcare between co-infected individuals and those who are not infected with both HIV and HCV.
On average, co-infected individuals in the community were eight years older, had been injecting for ten years longer, were far more likely to identify as non-heterosexual (21.5% versus 2.7%), and had more consistent access/use of health care (100% versus 81.4%). Co-infected individuals also shared injection equipment less frequently, presumably to prevent infection of their injection partners. The team examined gender, annual income, homelessness, and education level as well, though these rates were roughly the same between co-infected and uninfected individuals. Many of these findings were not surprising: researchers expect older individuals who have spent longer amounts of time injecting to have higher rates of co-infection; gay, lesbian, and bisexual individuals are likely to engage in sexual behaviors that increase risks of infection which are inflated by risky injection behaviors; and co-infected individuals have greater access to care because government health insurance policies often provide care for HIV, but not for Hepatitis C.
The findings presented here are significant and meaningful, but more research still needs to be done. The data sample analyzed in this paper was fairly small (19 individuals of 315 interviewed participants), and though this sample was representative of broader co-infection rates (6%), the small sample size could have skewed the results presented in this paper. Overall, this paper serves to identify the issues and areas of interest concerning co-infection in injection drug use networks. Now that differences have been identified, the team is calling for further research and for possible intervention strategies to be established that target characteristics at-risk for co-infected injection drug users.