Back HCV Prevention HCV Sexual Transmission HIV-Negative Gay Men May Be Susceptible to Sexually Transmitted Hepatitis C

HIV-Negative Gay Men May Be Susceptible to Sexually Transmitted Hepatitis C

alt

Several studies have shown that hepatitis C virus (HCV) can be sexually transmitted among HIV-positive men who have sex with men, but HIV-negative gay and bisexual men may be at risk as well if they share similar risk factors, according to a report in the June 2015 Journal of Viral Hepatitis.

Starting in the early 2000s researchers in the U.K. and elsewhere in Europe began reporting clusters of apparently sexually transmitted acute HCV infection among HIV-positive gay men in major cities; similar outbreaks followed in the U.S. and Australia. Various risk factors have been implicated -- including condomless anal sex, fisting, group sex, other sexually transmitted infections (STIs), and recreational drug use -- but these have not been consistent across studies.

Experts have traditionally assumed that sexual transmission of HCV is rare, based on studies of HIV-negative heterosexual couples. But the risk appears higher among people with multiple sex partners. Most studies to date have found that the risk of HIV-negative gay men becoming infected with HCV through sex is very low, but not zero. It is not yet clear why HCV sexual transmission is more common among HIV-positive men, since it can occur in people who still have well-preserved immune function with high CD4 T-cell counts.

Katie McFaul from Chelsea and Westminster Hospital and colleagues performed a retrospective study of acute hepatitis C among a population of HIV-negative gay and bisexual men in London. Their findings were previously presented in part at the 2014Interscience Conference on Antimicrobial Agents and Chemotherapy.

The researchers looked at data from all HIV-negative men who have sex with men (MSM) who had positive HCV antibody tests at sexual health clinicsbetween January 2010 and May 2014. They used European AIDS Network (NEAT) criteria to determine acute infection, indicated by a positive HCV antibody or HCV RNA test following a documented negative test. Other criteria included ALT liver enzyme elevation following a normal level or clinical symptoms such as fever, fatigue, nausea, jaundice, or upper abdominal pain.

Results

  • A total of 44 HIV-negative men fulfilled the criteria for acute hepatitis C:

o   10 men (23%) were HCV RNA negative at baseline and classified as having prior spontaneous HCV clearance;

o   15 men (34%) previously had a negative HCV antibody test within the prior year;

o   11 men (25%) had significant ALT elevations;

o   18 men (41%) were clinically diagnosed based on exposure risk and history.

  • Two-thirds of the HIV-negative menwith acute hepatitis C were white and the median age was 37 years.
  • The men reported a median of 2 and an average of 7 sex partners (range 1-100).
  • Most had HCV genotype 1 -- the most common type in the U.K. -- though a few had genotypes 3 or 4.
  • 41 men (93%) reported anal sex without condoms; most (88%) were both tops and bottoms, but 4 reported only receptive and 1 reported only insertive intercourse.
  • Substantial proportions reported other potential risk factors for HCV infection:

o   12 (27%) engaged in group sex;

o   11 (25%) practiced fisting;

o   16 (36%) reported nasal drug use and 9 (21%) reported injection drug use;

o   14 (32%) said they had unprotected sex while using recreational drugs.

o   13 men (30%) had a co-existing sexually transmitted infection at the time of acute hepatitis C diagnosis.

  • 29 men said they were aware of a partner's HIV or HCV status, including 2 (5%) who had sex with a known HCV monoinfected partner, 13 (30%) who did so with an HIV-monoinfected partner, and 6 (14%) who did so with an HIV/HCV coinfected partner.
  • 8 men (18%) had received HIV post-exposure prophylaxis (PEP) within the 6 months prior to HCV diagnosis, and 2 men (5%) were participants in a HIV pre-exposure prophylaxis (PrEP) trial.
  • 15 men with acute infection (34%) experienced spontaneous HCV clearance, while 11 (25%) received hepatitis C treatment.

Looking at testing practices, based on the number of HIV-negative MSM seeking sexual health services who received an HCV test in a typical month, McFaul's team estimated that fewer than 35,000 HIV-negative men -- or about 15% -- had been screened for HCV, while nearly 200,000 were not screened.

"HIV-negative MSM remain at risk of HCV infection, sharing similar risk behaviors as HIV-positive MSM," the study authors concluded. "HCV testing should be part of routine sexual health screening in those with risk factors, particularly in environments with high HCV prevalence."

Though the rate of acute HCV diagnosis was low in this population -- 44 out of more than 34,000 HIV-negative men, or less than 1% -- the researchers consider it an important yet under-researched issue.

"Accurate history taking, documentation of drug use, and risk prevention strategies are crucial in this population," they wrote. "Larger, prospective data are needed to further clarify the incidence and prevalence of hepatitis C in MSM without HIV infection."

7/9/15

Reference

K McFaul, A Maghlaoui, M Nzuruba, et al. Acute hepatitis C infection in HIV-negative men who have sex with men. Journal of Viral Hepatitis 22(6):535-538. June 2015.