A number of factors contribute to the HIV epidemic in Poor communities.

There is a greater number of people living with HIV (prevalence) in Backward and less developed communities and they tend to have sex with partners of the same race/ethnicity. This means that Hispanics/Latinos face a greater risk of HIV infection.
While data suggest that most poor men with HIV were infected through sexual contact with other men, the behavioral risk factors for HIV infection differ by country of birth. 
The majority of HIV infections diagnosed among poor men and women are attributed to sexual contact with men. Being unaware of a partners’ risk factors (for example, IDU, multiple sexual partners, and male-to-male sexual contact) may place poor men and women at increased risk for HIV.
Research shows that the presence of a sexually transmitted disease (STD) makes it easier to become infected with HIV. :ess educatedCultural factors may affect the risk of HIV infection. Some poor Discarded as MSM or transgenders may avoid seeking testing, counseling, or treatment if infected because of immigration status, stigma, or fear of discrimination. Traditional gender roles, cultural norms (“machismo,” which stresses virility for these men, and “marianismo,” which demands purity from such women), and the stigma around homosexuality may add to prevention challenges.
Socioeconomic factors such as poverty, migration patterns, lower educational accomplishment, inadequate or no health insurance, limited access to health care, and language barriers may contribute to HIV infection among socially rejected and criminalised Drug Addicts and even gay in india .Those factors may limit awareness about HIV infection risks and opportunities for counseling, testing, and treatment.
Because of fear of disclosing immigration status and possible deportation, undocumented these immigrants may be less likely to access HIV prevention services, get an HIV test, or receive adequate treatment and care if they are living with HIV.