In San Francisco, low-income transgender women have a high prevalence of HIV that has apparently remained stable throughout the current decade. However, signs indicate that the rate of new infections in this population is declining.

Publishing their findings in the Journal of Acquired Immune Deficiency Syndromes, researchers conducted a study of trans women in San Francisco that was carried out in three phases, in 2010, 2013 and 2016. The researchers used a method known as respondent-driven sampling to recruit participants in which they first recruited a series of trans women of diverse demographics; then they asked these “seed” individuals to recruit others for the study through their own social networks.

The participants needed to be 18 years old or older, a resident of San Francisco, designated male at birth, currently identify as something other than male and speak English or Spanish.

In the 2010 phase, the researchers recruited 11 seed individuals and wound up with 314 total participants. In 2013, there were 12 seeds and 234 total participants. And in 2016, there were 16 seeds and 318 total participants.

In each of the three phases of the study, 2.9 to 3.3 percent of participants were Asian, 18.9 to 29.3 percent were Black, 26.9 to 32.9 percent were Latina, 17.6 to 26.1 percent were white and 15.9 to 18.9 percent were of an “other” race. More than 90 percent of the women in each year had an income below $30,000. About two thirds of the trans women were born in the United States. A total of 43.8 to 47.8 percent identified as female, and 45.7 to 52.8 percent identified as trans women.

The study did not assess use of Truvada (tenofovir disoproxil fumarate/emtricitabine) as pre-exposure prophylaxis (PrEP) in 2010. No participant reported using PrEP in 2014. An estimated 10.9 percent used Truvada for prevention in 2016.

In 2010, 2013 and 2016, 38.8 percent, 33.7 percent and 31.6 percent of the participants tested positive for HIV, respectively. This indicated that the overall HIV prevalence in this population was stable between the three years. A respective 91.1 percent, 83.5 percent and 92.1 percent of the women who tested positive during each year already knew they had the virus. Again, this trend was considered stable.

By comparison, about 24 percent of men who have sex with men (MSM) in the city are living with HIV; an estimated 97 percent of them are diagnosed.

After adjusting the data to account for various differences between the participants, the study authors concluded that, compared with whites, nonwhite trans women had consistently higher odds of being HIV positive. Specifically, compared with whites, Asians had an 11.3-fold, 49.3-fold and 5.8-fold increased likelihood of testing positive in 2010, 2013 and 2016, respectively; Blacks had a respective 21.3 percent, 5.8 percent and 9.7 percent increased likelihood of having HIV; and Latinas had a respective 6.7-fold, 4.9-fold and 2.9-fold increased likelihood of having the virus.

Trends varied across the years of the study according to age. In 2010, compared with participants 46 years old and older, those 26 to 35 years old were 2-fold more likely to have HIV and those 36 to 45 years old were 2.2-fold more likely to have the virus. In 2013, compared with those age 46 years old and older, those 18 to 25 years old were 90 percent less likely and those 36 to 45 years old were 40 percent less likely to test positive for HIV. In 2016, those 18 to 25 years old were 70 percent less likely than those age 46 years old and older to test positive.

In 2010, college graduates had an 80 percent lower likelihood of testing positive compared with those with just a high school diploma. In 2013, those with some college had a 40 percent lower likelihood of testing positive compared with those with just a high school diploma. And in 2016, compared with those with just a high school diploma, those with some college education and those with a college degree were, respectively, 50 percent less likely and 91 percent less likely to have HIV.

Income was not associated with differences in the chance of testing positive for the virus. However, because the study population was almost wholly made up of low-income individuals, it would not have been possible to draw comparisons between those of considerably different income brackets.

In 2010, compared with those who reported renting a home, those living with family, friends or a partner were 95 percent less likely to test positive for HIV and those reporting being homeless or living in a shelter were 70 percent less likely to have the virus. In 2013, compared with renters, those who lived in a hotel or rooming house and those who were homeless or lived in a shelter were, respectively, 30 percent and 40 percent less likely to test positive. In 2016, compared with renters, those living in a hotel or rooming house were 50 percent less likely to have HIV.

The year of the study was not associated with a difference in the overall HIV diagnosis rate, leading the researchers to conclude that prevalence of the virus among trans women in San Francisco remained high and stable over time.

However, because of the higher rate of HIV among older trans women over the last two years of the study, the researchers hypothesized that the new infection rate among low-income trans women might have declined in recent years.

To read a press release about the study, click here.

To read the study abstract, click here.