Violation of the vaginal microbiome and the risk of HIV infection in women

Women are the main population responsible for new HIV infections and the persistence of the HIV pandemic. The article provides a review of the current literature on the factors and mechanisms by which the vaginal microbiome can contribute to HIV infection. A key determinant of susceptibility to HIV infection is the composition of the vaginal microbiome, which can influence the local immune cell population and inflammation status. A low diversity microbial composition dominated by Lactobacillus crispatus does not increase the risk of HIV infection, and a high microbial diversity environment associated with bacterial vaginosis increases the risk of HIV infection. The female reproductive tract has a unique susceptibility to viral infection because tissue-specific immunity must elicit rapid antimicrobial responses to pathogens while maintaining sperm tolerance. It is important to note that the risk of HIV infection during sexual intercourse is multifactorial and is determined not only by the state of the microbiota of a woman’s genital tract, but also by the state of the partner’s microbiota, the viral load of HIV in the blood of the sexual partner, the presence/absence of anti-retroviral therapy in the partner, hormonal background and the phase of the menstrual cycle, which also affect the state of the microbiota.