Prevalence and incidence of hepatitis C virus infection in men who have sex with men: a systematic review and meta-analysis

BACKGROUND

WHO has set targets for hepatitis C virus (HCV) elimination by 2030. We did a global systematic review of HCV prevalence and incidence in men who have sex with men (MSM) to provide updated estimates that can guide community education and public health policy.

METHODS

We did a systematic review and meta-analysis of studies published and listed on MEDLINE or Embase between Jan 1, 2000, and Oct 31, 2019, including conference proceedings. Studies were eligible if they reported measures of HCV prevalence or HCV incidence (or both) among MSM. Studies that relied on participants' self-reported HCV status with no laboratory confirmation were excluded. Pooled HCV estimates in MSM were stratified by HIV status and by injecting drug use, then by WHO region and by income level. Random-effects meta-analysis was done to account for between-study heterogeneity and examined using the I² statistic. Pooled HCV prevalence was also compared with HCV estimates in the general population and presented as prevalence ratios (PRs). In HIV-negative MSM, incidence estimates were stratified by use of HIV pre-exposure prophylaxis (PrEP). The systematic review was registered with PROSPERO, number CRD42020156262.

FINDINGS

Of 1221 publications identified, 194 were deemed to be eligible and included in the systematic review and meta-analysis. Overall, the pooled HCV prevalence in MSM was 3·4% (95% CI 2·8-4·0; I²=98·0%) and was highest in Africa (5·8%, 2·5-10·4) and South-East Asia (5·0%, 0·0-16·6). Globally, HCV prevalence was 1·5% (1·0-2·1) in HIV-negative MSM and 6·3% (5·3-7·5) in HIV-positive MSM. Compared with the general population, HCV prevalence was slightly higher in HIV-negative MSM (PR 1·58, 95% CI 1·14-2·01) and markedly higher (6·22, 5·14-7·29) in HIV-positive MSM. Pooled HCV prevalence was substantially higher in MSM who had ever injected drugs (30·2%, 22·0-39·0) or currently injected drugs (45·6%, 21·6-70·7) than in those who never injected drugs (2·7%, 2·0-3·6). In HIV-negative MSM, the pooled HCV incidence was 0·12 per 1000 person-years (95% CI 0·00-0·72) in individuals not on PrEP and 14·80 per 1000 person-years (9·65-20·95) in individuals on PrEP. HCV incidence in HIV-positive MSM was 8·46 per 1000 person-years (6·78-10·32).

INTERPRETATION

HIV-positive MSM are at substantially increased risk of HCV. Overall, HIV-negative MSM had a slightly higher prevalence of HCV than the general population but had a lower prevalence than HIV-positive MSM. High HCV incidence in more recent PrEP studies suggests that as PrEP use increases, greater HCV transmission might occur. HCV burden in MSM varies considerably by region, which is likely to be associated with variation in the prevalence of injecting drug use and HIV.

FUNDING

World Health Organization.

Is sexual contact a major mode of hepatitis C virus transmission?

Medical opinion varies considerably regarding the transmission of hepatitis C virus (HCV) through sexual contact. Based on the study design, representativeness of the study population, and the methods used for case ascertainment, we analyzed 80 qualifying reports regarding the evidence for or against sexual transmission. Regarding heterosexual transmission, the weight of evidence is that there is no increased risk of sexual transmission of HCV among heterosexual couples in regular relationships. This risk increases among persons with multiple sexual partners (adjusted odds ratio [aOR] 2.2-2.9), but this association may be confounded by increased likelihood of injection drug use with increased number of partners. There appears to be a real increased risk for women coinfected with human immunodeficiency virus (HIV) or other sexually transmitted infections (aOR 3.3-3.9) and especially for HIV-infected gay men who are having sex with one another compared with HIV-uninfected men (aOR 4.1-5.7). HIV-infected gay men increase their risk of such transmission in association with practices that lead to mucosal trauma (multiple sexual partners, fisting, use of sex toys) and the presence of genital ulcerative disease.

CONCLUSION

This review should inform, and not distract from, recommendations to reduce the risk of HCV transmission. Health care providers need to pay special attention to sexual transmission of HCV among HIV-infected individuals.