A study links anal sex & meth to increased HCV rates among MSMs
by Larry Buhl
LifeGuide [Hep Talk]
For decades it has been the conventional wisdom that hepatitis C is transmitted primarily by exposure to blood containing the hepatitis C virus (HCV) and that transmission rarely occurs from exposure to other infected body fluids, such as semen. Even now the CDC doesn’t recommend routine condom use to prevent transmission. But prevention messages could change quickly after studies in the U.S. and Europe have shown that HCV is a risk for men who do not use IV drugs but do have unprotected receptive anal sex with men.
The most recent study was conducted by Dr. Daniel Fierer, an infectious diseases expert at the Mount Sinai School of Medicine, and published in July in the Centers for Disease Control and Prevention’s Morbidity and Mortality Weekly Report.
Fierer his colleagues concluded that uninfected men who have unprotected anal sex with HCV-positive men, especially while high on crystal meth, are at very high risk of contracting the hepatitis C virus. Dr. Fierer’s group controlled and matched men by ethnicity and age and excluded those who had other risk factors for HCV, such as IV drug use. “We excluded men who had ever injected anything,” Fierer tells A&U.
The research team gave detailed questionnaires to thirty-four HIV-positive men with new hepatitis C infections, as well as to sixty-seven closely matched HIV-positive men who tested negative for HCV. Statistical analysis revealed two factors that independently raised an HIV-positive man’s risk of HCV infection:
• Receptive anal intercourse with ejaculation of the partner increased HCV risk twenty-three-fold.
• Having sex while high on methamphetamine increased HCV risk nearly twenty-nine-fold.
“The sexual route of transmission is very clear,” Fierer says, adding that the data do not support sexual HCV transmission between HIV-negative men.”
The study did not determine why being HIV-positive with HCV increased the risk of HCV transmission. But it is known that, for whatever reason, when HIV-positive men get HCV, they have much higher levels of the hepatitis C virus in their blood.
Fierer warns that, while semen is implicated in transmission, his results do not suggest that anal sex without ejaculation is safe. A recent study of outbreaks of HCV among HIV-positive German men that suggests prolonged or traumatic anal intercourse often exposes both partners to infected blood.
Fierer says they cannot yet determine exactly why crystal meth is so risky, but that it does lower inhibition and may lead men who have sex with men to have rougher sex or longer-lasting sex.
Fierer’s study underscores what many healthcare practitioners have been seeing, that there is an explosion of hepatitis C among men who have sex with men. Liver cancer and cirrhosis caused by HCV are now the leading cause of death among people with HIV infection who have access to HIV drugs. Some thirty percent of Americans with HIV are coinfected with HCV. And even after being cured with an antiretroviral drug regimen, a person can be reinfected with hepatitis C, which means drug resistance can become an issue.
Another open question is: Why is HCV suddenly more likely to be transmitted through certain sexual practices? “It is possible that [HCV transmission through anal sex] has reached some kind of critical mass of people,” Fierer tells A&U. “But like HIV spread in the early days, you have all sorts of behavioral factors and just bad luck to come up with the perfect storm. We are reasonably sure it is not a special or mutant virus because the four genotypes [of HCV] are all very different.”
For now, the prescription is awareness and risk reduction. “HIV-infected men must take steps to protect themselves and others by using condoms when having sex and by avoiding crystal methamphetamine,” Fierer says. “I hope the CDC will start to amend its guidelines and that providers will begin counseling patients differently. Healthcare providers must understand the need to screen for HCV on a regular basis for those at risk.”
Larry Buhl is a freelance journalist and screenwriter living in Los Angeles.