The study from Lima also found that the partners of transgender women form a distinct group, in general, from gay and bisexual men. There was a minority of men who have sex with men among the trans women’s sexual partners, but they had different characteristics from their other partners.
Participants were recruited through respondent-driven sampling. This involves engaging ‘seeds’ who are volunteers who then recruit their social contacts to the study.
However, as Dr Long commented, “The partners of transgender women do not form a social network.” Her team therefore asked transgender female “seeds” to recruit their sexual partners into the study, who were then asked to recruit their sexual partners. Eleven seeds recruited partners and formed clusters ranging in size from four to 250 people. The longest 'chain' was eleven people long, i.e. the last person in the chain was ten sexual links away from the seed.
A diagram of the people recruited for the study shows very clearly that most of the transgender seeds recruited a ‘first wave’ of cisgender men who in turn recruited a second wave of transgender women, who then recruited a third wave of cisgender men. (See above for the diagram, where transgender women are the green circles and cisgender men blue diamonds.) However, a few of the cisgender men are also linked to other men, indicating male/male sex.
The eleven seeds recruited 27 partners, 25 cisgender men, one cis
woman and one trans woman. This 'first generation' then recruited another 45
partners, of whom 11 were cisgender men, two cisgender women, and 32
transgender women.
Of the 203 partners of trans women, 97% were cis men. Only two partners were cis women and five were trans women. These partners reported that their own recent sexual partners were trans women (100%), cis women (55%) and cis men (7%).
In other words, there was a remarkable degree of segregation between the groups. This questions the hypothesis of the US study that there might be a lot of direct sexual transmission happening between trans women, or between the male partners of trans women and other cis men. It's important though to remember that two different cities and cultures are involved here.
Participants’ reports of who they were sexually attracted to closely
resembled the people they reported having sex with. In particular, 83% of
the partners of trans women reported they were attracted to trans
women and 68% to cisgender women. But only 8.9% reported being attracted
to cisgender men.
The minority of men who had sex with men were very different from the other partners of trans women. They were nine times more likely to identify as homosexual and nearly five times as likely to know their HIV status as the other partners.
While the proportion of partners of trans women who knew they had
HIV was lower, at 3.5%, than it was among men who had sex with men (11.6%), or among trans women (5.6%), this is still ten times higher than prevalence
in the general male population in Peru. In addition, only 46% knew
their HIV status compared with 58% of transgender women and 78% of men who have sex with men, so some could have HIV but not know it.
One finding was that transgender women and their partners had a lot of transactional sex (for money, food, gifts or shelter) – but it was not always the women who were the 'sex workers' and the men who were the 'clients'. Ninety per cent of transgender women reported selling sex but so did 56% of their partners; 78% of the partners reported buying sex but so did 57% of the trans women. The minority of gay and bisexual men also often sold sex, but almost never bought it.
Dr Long commented that although the survey did not find a complete explanation of why HIV rates were higher in transgender women in general, it did find that their partners were separate from gay men and a risk group in themselves.