Within any community, the prevalence of HIV can vary among different populations.
Gay and bisexual men have the largest number of new diagnoses in the United States. Blacks/African Americans and Hispanics/Latinos are disproportionately affected by HIV compared to other racial and ethnic groups. Also, transgender women who have sex with men are among the groups at highest risk for HIV infection, and injection drug users remain at significant risk for getting HIV.
Risky behaviors, like having anal or vaginal sex without using a condom or taking medicines to prevent or treat HIV, and sharing needles or syringes play a big role in HIV transmission. Anal sex is the highest-risk sexual behavior. If you don’t have HIV, being a receptive partner (or bottom) for anal sex is the highest-risk sexual activity for getting HIV. If you do have HIV, being the insertive partner (or top) for anal sex is the highest-risk sexual activity for transmitting HIV.
Transgender women are 49 times more likely to be living with HIV than the general population. While transgender men are less likely to be HIV positive than transgender women, their infection rates are higher than those of the general population. The Centers for Disease Control and Prevention (CDC) suggests that certain risk factors are directly associated with transphobia, and the marginalization faced by transgender people can contribute to such high infection rates. These risk factors include "higher rates of drug and alcohol abuse, sex work, incarceration, homelessness, suicide attempts, unemployment, lack of family support, violence, stigma and discrimination, limited access to health care, and negative experiences during medical care appointments. " Essentially, because they live in a society where there is significant stigma and discrimination against transgender people, they are forced into situations that greatly increase their risk of contracting HIV and severely limit their chances of obtaining adequate medical care once that are infected.