A global systematic review commissioned by the WHO finds a high prevalence and incidence of HCV among men who have sex with men

In collaboration with the Kirby Institute at UNSW Sydney, Australia, the WHO announced today systematic review and meta-analysis of the prevalence and incidence of hepatitis C virus (HCV) infection in men who have sex with men (MSM) in The Lancet Gastroenterology & Hepatology.

Globally, it is estimated that 71 million people have chronic HCV infection, and 1.75 million new infections are estimated each year.

The WHO has set goals for the elimination of the hepatitis C virus by 2030. This ambitious goal is at hand because with effective prevention measures, direct-acting medicinal antiviral drugs (DAAs) for HCV are now available. Although HCV transmission primarily occurs through drug injection and unsafe injection in healthcare facilities, sexual transmission can also occur, especially through unprotected anal intercourse.

The WHO commissioned this systematic review and meta-analysis to summarize global evidence on the prevalence and incidence of HCV infection among MSM and to examine the association with HIV and injecting drug use. The results are presented in this paper.

Of the 1221 publications identified, 194 were assessed as acceptable and included in the meta-analysis.

“The findings from this review show that MSM populations globally have a high burden of HCV infection, with significant differences across countries and regions,” states lead author Jeff Jin of UNSW in Sydney. In this review, the overall pooled prevalence of HCV in MSM was 3.4% (95% CI: 2.8–4.0).

The publication confirms the increased risk of HCV in HIV-positive MSM. The review found that the global combined prevalence of HCV in HIV-positive MSM was 6.3% (95% CI: 5.3-7.5) compared to 1.5% (95% CI: 1). 0-2.1) in HIV-negative MSM. The difference in the combined prevalence of HCV between HIV-positive and HIV-negative MSMs was greatest in the WHO European Region, followed by the WHO Western Pacific and American regions. This increased prevalence of HCV among HIV-positive MSM accounts for a large portion of the additional burden of HCV observed among MSM relative to the general population.

The use of drug injections is a major factor in HCV transmission globally and is also an important risk factor for HCV transmission among MSM populations. MSMs with a history of injecting drug use are significantly more likely to be HCV positive than non-injecting MSMs. The cumulative prevalence of HCV was significantly higher in MSMs who were ever (30.2%, 95% CI: 22.0-39.0) or currently (45.6%, 95% CI: 21.6 – 70.7) injected drugs compared to those who never injected (2.7%, 95% CI: 2.0–3.6).

“Reaching and supporting MSM that also injects drugs with tailored and effective prevention, testing, and treatment services is crucial,” says Dr. Niklas Luhmann, technical officer at the WHO World Programs for HIV, Hepatitis and Sexually Transmitted Infections.

Global data on the incidence of HCV among MSM were also reviewed. A total of 46 studies reporting the incidence of HCV in MSM were included. The analysis showed that new infection rates were highest in HIV-positive MSMs with a combined HCV incidence of 8.46 (95% CI: 6.78–10.32) per 1,000 person-years, and in several recent HIV studies -negative MSM taking pre-exposure prophylaxis (PrEP) (combined HCV incidence of 14.80 (95% CI: 9.65-20.95) per 1000 person-years).

This higher incidence of HCV observed in MSMs taking PrEP may be due to several factors: MSMs who chose PrEP usually do so because they themselves have identified a higher risk of HIV and barriers to consistent condom use. They may also have greater sexual mixing with HIV-positive MSM who, as mentioned above, have a higher prevalence of HCV than HIV-negative MSM. Furthermore, the reviewed studies found that high-risk HIV-negative MSMs who choose PrEP have a high prevalence of HCV viremia prior to initiating PrEP. This higher risk for HCV observed in HIV-negative men taking PrEP may therefore be prior to the date of PrEP use, rather than related to changes in sexual behavior and condom use after the start of PrEP.

“We know we need to improve access to the prevention, testing and treatment of severely affected and sometimes marginalized populations to achieve our goals of eliminating hepatitis,” said Dr. Meg Doherty, director of the WHO World Program on HIV, Hepatitis and Sexually Transmitted Infections. “This first global systematic review of HCV prevalence and incidence in MSM populations emphasizes that greater efforts are needed to support access to HIV, HCV prevention, testing, and treatment for high-risk MSM. Existing HIV and PrEP programs for MSM should include HCV testing and treatment and offer tailored prevention interventions. ”