An estimated 2.3 million people around the world are currently living with both HIV and hepatitis C virus (HCV), more than half of whom are people who inject drugs, show new findings published online in The Lancet Infectious Diseases. Sponsored by the World Health Organization (WHO), the study is the first global estimate ever recorded on the prevalence of HIV/HCV coinfection as a public health concern.

Currently, global statistics show that there are 37 million HIV-positive people worldwide, and that around 115 million people are living with a chronic hep C infection. However, until now, very little was known about how the two epidemics overlapped.

For this latest study, researchers at the University of Bristol and the London School of Hygiene and Tropical Medicine systematically reviewed 783 medical studies from around the world to build a detailed estimate on HIV/HCV coinfection. The purpose of the study was to update current WHO guidelines on the screening of coinfections and the initiation of treatment for both diseases.

Ultimately, researchers found that people living with HIV are six times more likely to have hep C than those who are HIV negative. The study also showed that worldwide, people who inject drugs have an extremely high prevalence, upwards of 80 percent. The report also demonstrated that recent drug-related coinfections are particularly high in areas like eastern Europe, sub-Saharan Africa and central Asian countries.

Researchers said the findings highlight the need for more combined strategies to help combat hep C and HIV together around the world, including scale ups in global prevention interventions, syringe exchanges and opioid substitution therapy, as well as access to treatment for both HIV and hep C to help reduce morbidity and prevent the spread of the diseases.