New Technique May Help Prevent HIV Infection

Rectal microbicide formulated as an enema may inhibit the spread of HIV and other sexually transmitted infections.

Enemas are commonly used among men who have sex with men (MSM) and transwomen (TW) before sexual intercourse.

However, these groups are at particular risk to HIV and a host of other sexually transmitted infections because enemas can seriously damage the lining of the rectum, allowing for easier transmission of harmful viruses and bacteria.

A research group working with Peruvian MSM and TW recently proposed a solution to this problem: a rectal microbicide formulated as an enema to prevent HIV and possibly other sexually transmitted infections.

“A douche-based rectal microbicide that is safe and effective could play an important role by providing another HIV prevention option for these highly vulnerable groups,” said research lead Brandon Brown, an assistant professor in the School of Medicine at the University of California at Riverside. “In view of the expanding global HIV epidemics in MSM and TW, there is an urgent and immediate need for novel HIV prevention options, such as the douche-based rectal microbicides we propose, that can be readily incorporated into existing sexual practices."

The team of scientists examined the prevalence of enema use among 415 MSM and 68 TW in Lima, Peru.

“While we conducted the study among MSM and TW in Peru, our findings may extend to these groups locally and globally,” Brown said. “Unfortunately, little is known about rectal douching practices among these groups and the damage such practices may cause.”

Participants completed an interview about their rectal douching practices to inform rectal microbicide douche development. Six months prior, 18% of participants reported rectal douching as a regular practice, and those who did so often played a receptive sexual role.

“We found that men who douched prior to sex did it primarily for hygiene and pleasure. We should capitalize on these reasons to increase this practice and eventually include a rectal microbicide for HIV prevention,” Brown said.

The study was conducted at a free/low-cost gay men’s health center in Lima that provides social services for MSM and TW. The researchers invited MSM and TW who attended the center for any reason to participate in the study.

Other participants were recruited from bars, clubs, volleyball courts, and social media. MSM and TW also referred each other to the study.

“Based on the findings from this study and previous studies on rectal microbicides, we need to learn more about the sexual practices and beliefs among diverse MSM and TW,” Brown said. “In the absence of the availability of oral antiretroviral pre-exposure prophylaxis or PrEP in Peru and globally we need to explore additional venues for HIV prevention. Rectal microbicides are one possible cost-effective tool to prevent HIV.”

Brown explained that oral PrEP may not be an ideal route for everyone to take, and not all MSM and TW use lube for sex.

“The more we know about rectal douching practices, the better situated we will be for developing interventions with rectal microbicides,” he said.