The trend of gay men choosing to have sex with men of the same HIV status is universally credited with helping to bring about falling rates of HIV infections in San Francisco. But the practice, known as serosorting, has yet to receive an official stamp of approval from the health department and most of the city's AIDS agencies.

Health officials, AIDS advocates, and some gay men continue to question whether promoting serosorting is such a good idea. Supportive of the premise behind serosorting – gay men's desire to prevent the transmission of HIV – they said their main concern about the practice is that many men also view serosorting as a way to have condomless sex.

For negative men who opt to serosort, they may be putting themselves at risk for HIV because there is no guarantee the men they are meeting are indeed HIV-negative. As for positive men, the risk is contracting other sexually transmitted diseases or new strands of the virus.

"There is no official department policy on serosorting," said Tracey Packer, the city's interim HIV prevention director. "This is a strategy coming from the community."

Nonetheless, Packer said she acknowledges and is supportive of the fact that "gay men say it is a way they can have sex and decrease the risk of being infected or infecting someone else."

Robert McMullen, executive director of the Stop AIDS Project, said the city's position is the right one to take. While serosorting may work for some gay men, McMullen said he is not ready to have his agency promote its use on a community-wide scale.

"It is not our responsibility to be encouraging people to do things that have an element of risk involved with them just because they may be, overall, a good public health strategy," he said. "It is a loaded gun, if you will, unless people are getting tested quite often."

Health department researchers have applied for a grant to study serosorting and its impacts. But without the data to prove otherwise, Packer said she is concerned that serosorting is based on a certain amount of blind faith that a person's sexual partner who says he is negative is in fact negative.

"Serosorting is only as good as the honesty of the people involved," she said.

Still others oppose seeing serosorting adopted as official policy because they argue it ghettoizes gay men from other gay men and builds barriers in the community between the haves (men who are HIV-positive) and the have-nots (HIV-negative men).

"Eighteen years ago I met a man who was HIV-negative and I was positive. We are still together and we are still serodiscordant. I would never have met him if I had serosorted," said Randy Allgaier, co-chair of the HIV Health Services Planning Council. "It is a pretty new phenomenon. There needs to be a little more discussion and data before I feel comfortable we should do this. Serosorting, while a prevention effort, cuts you off from potential, wonderful partners."

SFAF campaign

The San Francisco AIDS Foundation, however, is about to become the first AIDS agency in the country to discuss serosorting in a social marketing campaign. The agency plans to launch advertisements and a Web site this June that will not only discuss serosorting but other controversial methods like "negotiated safety" or seropositioning – where a negative man will only top or a positive man will only bottom during sex.

"I think that the leveling off or slight reduction of HIV infections in San Francisco is due primarily to serosorting and

Researcher Dr. Robert Grant

what we call negotiated safety," said Steven Tierney, deputy director for programs and services at SFAF. "We didn't think it up. Guys are using it in order to improve their health while still having fun. It is a good thing guys are making that decision."

But when asked if the ads will be an endorsement of serosorting, Tierney described the campaign being more informational than promotional.

"I don't think it is a matter of endorsing it. It is another tool that guys can use and are using," he said. "We think some guys have been doing it and others don't quite know what it is, so the social marketing campaign is designed to increase community dialogue on what does serosorting mean and what does negotiated safety mean. How can you have the sex life you want to and deserve but ultimately be concerned about your sexual health and the health of your partners?"

Jeff McConnell, a researcher at the J. David Gladstone Institutes, has been studying serosorting among positive men since the late 1990s. He said he agrees that serosorting among positive men has led to drops in the HIV rates, but he is unsure of how serosorting impacts negative men.

"Part of the hesitance we share is we study only serosorting in HIV-positive men. Until recently, no one I know intentionally studied it in HIV-negative men," he said. "The real problem with negatives is it is hard to be sure about your partners' status. People seroconvert unexpectedly."

When counseling gay men McConnell cautioned that health workers need to carefully evaluate what they say about serosorting and to whom they say it.

"If you are talking to a guy who uses condoms all the time and has a perfect record, you wouldn't want to counsel him on serosorting. On the other hand, if you are counseling an individual who cannot use condoms consistently or refuses to use them, you do want to talk to them about serosorting," he said.

Dr. Robert Grant, who along with McConnell has worked on the Positive Partners study for the last eight years, said their data shows strong evidence for promoting serosorting among positive men.

"We think that serosorting is a prevalent and potentially very effective way to decrease the amount of transmission that occurs in populations," said Grant. "We study seropositive serosorting. We see in our cohort it happens frequently. A large portion of unprotected sex is occurring between HIV-positive partners where there is no chance of passing HIV in those partnerships. It appears to decrease the spread of HIV infection."

But having a health department promote serosorting may in fact backfire, said Grant. He argued there are other strategies health officials can promote that would help foster serosorting.

"I think it is because who someone chooses to be their sexual partner is a very personal decision. I think that it may be deemed inappropriate for public health messages to recommend one type of partnership over another," he said. "I think in San Francisco what you do see promoted, and in other places as well, is testing and disclosure to prospective partners. They are the foundation for which serosorting can occur."

Condoms still needed

With negative men who serosort, those interviewed stressed they still need to use condoms because there is no guarantee that their sexual partners are indeed negative.

"A condom is not as variable as somebody's honesty," said Allgaier. "I want to assume people are being honest but I can't assume that. Some people will tell a future partner who they think is hot whatever that person wants to hear."

A recent study on gay men living in Washington state's King County, which includes Seattle, raised questions about the veracity of negative men who serosort. The study found that in King County, as many as half of the persons with newly diagnosed HIV infections denied having unprotected anal intercourse with someone who was positive, suggesting that serosorting often fails, concluded the study's author, Dr. Matthew Golden, an assistant professor at the University of Washington Center for AIDS and STDs in Seattle and director of the STD control program at Public Health Seattle and King County.

"The risk of bacterial sexually transmitted diseases in MSM who serosort is comparable to that of MSM who do not, and is significantly higher than that observed among men who deny all unprotected anal intercourse. At a population level, the prevention implications of serosorting are complex, substantially undefined, and depend on the extent to which the practice is an alternative to safer or less safe sexual behaviors," wrote Golden. "Serosorting is common and provides substantial, but imperfect, protection against HIV. Efforts to increase serosorting, particularly if coupled with efforts to increase the frequency of HIV testing, would probably decrease HIV transmission as long as they were not associated with substantial increases in overall unprotected sex."

In an interview this week, Golden said he is convinced serosorting "is not a completely safe strategy" for negative men. He said that in both Seattle and San Francisco, based on data from several studies he reviewed, about one-quarter to one-third of new HIV infections is "the consequence of sex between two men who both say they are negative."

"The best strategy from my perspective is to serosort and use condoms. But I recognize that is not what everyone does," said Golden. "People aren't stupid but it kind of makes sense people are willing to take some risks. Most people want to mitigate their risks and don't want to use condoms all the time. This is the middle ground on it. The problem is it might not be a good middle ground."

Gay men long ago tuned out the mantra "use a condom every time" as a relic of the initial response to AIDS 25 years ago, so Golden said he is not surprised to see researchers and health officials look for new messages and strategies like serosorting to promote.

"No one is enthusiastically embracing this and saying, 'Yeah, let's tell everyone to serosort.' But everyone is trolling for something that will work," he said. "If there is anything to get out to people in a message it is this is not completely safe and condom use is better. But if they are going to do this, they need to test really frequently [Golden advised every three months]. Otherwise the information they are giving people is bad and the information other people are giving them is bad."

Already, an increasing number of men are disclosing not only their HIV status but also when they took their last HIV test in online profiles or ads seeking sex. The Internet, said Golden, has been instrumental in allowing men to serosort because they can not only disclose their HIV status but also seek out men of the same status – something harder to do in a gay bar or bathhouse. For this reason he said serosorting is likely to play an increasingly larger role in HIV prevention strategies.

Serosorting, he said, "is not going to go away."