Researchers developed mathematical models to predict the association between the transmission of HIV and hepatitis C virus (HCV) infection transmission among people who inject drugs. The findings obtained may help in adopting strategies to prevent infection among people at risk.
The study detailing the models, “HCV Prevalence Can Predict HIV Epidemic Potential Among People Who Inject Drugs: Mathematical Modeling Analysis,” was published in the journal BMC Public Health.
Among people who inject drugs, the transmission of both HCV and HIV can occur by sharing non-sterile needles. HCV is transmitted more frequently than HIV, and has a high incidence among people who inject drugs.
According to the authors, 63 percent of this population worldwide is infected with HCV, and 19 percent with HIV. However, most HIV-infected people (82 percent) are also infected the HCV. Thus, HCV may be considered a marker of the risk of exposure to HIV, although studies addressing this relationship are lacking.
Researchers developed two mathematical models to simulate the evolution of HCV and HIV infection among people who inject drugs, and estimate the association between HCV prevalence and HIV prevalence in this population.
The analysis indicated that HCV is about eight times more infectious per shared injection than HIV, and the models successfully reproduced the actual time course of the HIV epidemic in Iran.
These findings support the hypothesis that HCV prevalence can be used to make predictions about HIV infection among intravenous drug users.
“Despite the complexity of the models and of the HCV-HIV association, these measures offered a simple applied tool for policy makers and program officers to predict HIV epidemic potential in PWID [people who inject drugs] populations,” the researhers wrote. “We also proposed several methods with varying levels of precision for predicting HIV epidemic scale, and this concept was demonstrated in a specific country, Iran.”
They concluded: “The methodology proposed … has a practical relevance which can be disseminated directly at the level of national stakeholders or in consultation with the international organizations leading the HIV/HCV response in the region, namely the World Health Organization, Joint United Nations Programme on HIV/AIDS, and the World Bank.”