Testing and treatment of sexually transmitted infections (STIs) can be an effective tool in preventing the spread of HIV, the virus that causes AIDS. An understanding of the relationship between STIs and HIV infection can help in the development of effective HIV prevention programs for persons with high-risk sexual behaviors.
Individuals who are infected with STIs are at least two to five times more likely than uninfected individuals to acquire HIV infection if they are exposed to the virus through sexual contact. In addition, if an HIV-infected individual is also infected with another STI, that person is more likely to transmit HIV through sexual contact than other HIV-infected persons (Wasserheit, 1992).
There is substantial biological evidence demonstrating that the presence of other STIs increases the likelihood of both transmitting and acquiring HIV.
Increased susceptibility. STIs appear to increase susceptibility to HIV infection by two mechanisms. Genital ulcers (e.g., syphilis, herpes, or chancroid) result in breaks in the genital tract lining or skin. These breaks create a portal of entry for HIV. Additionally, inflammation resulting from genital ulcers or non-ulcerative STIs (e.g., chlamydia, gonorrhea, and trichomoniasis) increase the concentration of cells in genital secretions that can serve as targets for HIV (e.g., CD4+ cells).
Increased infectiousness. STIs also appear to increase the risk of an HIV-infected person transmitting the virus to his or her sex partners. Studies have shown that HIV-infected individuals who are also infected with other STIs are more likely to shed HIV in their genital secretions. For example, men who are infected with both gonorrhea and HIV are more than twice as likely to have HIV in their genital secretions compared to those who are infected only with HIV. Moreover, the median concentration of HIV in semen is as much as 10 times higher in men who are infected with both gonorrhea and HIV than in men infected only with HIV. The higher the concentration of HIV in semen or genital fluids, the more likely it is that HIV will be transmitted to a sex partner.
Evidence from intervention studies indicates that detecting and treating STIs may reduce HIV transmission.
STI treatment reduces an individual’s ability to transmit HIV. Studies have shown that treating STIs in HIV-infected individuals decreases both the amount of HIV in genital secretions and how frequently HIV is found in those secretions (Fleming, Wasserheit, 1999).
Herpes can make people more susceptible to HIV infection, and it can make HIV-infected individuals more infectious. It is critical that all individuals, especially those with herpes, know whether they are infected with HIV and, if uninfected with HIV, take measures to protect themselves from infection with HIV.
Among individuals with both herpes and HIV, trials are underway studying if treatment of the genital herpes helps prevent HIV transmission to partners.
Strong STI prevention, testing, and treatment can play a vital role in comprehensive programs to prevent sexual transmission of HIV. Furthermore, STI trends can offer important insights into where the HIV epidemic may grow, making STI surveillance data helpful in forecasting where HIV rates are likely to increase. Better linkages are needed between HIV and STI prevention efforts nationwide in order to control both epidemics.
In the context of persistently high prevalence of STIs in many parts of the United States and with emerging evidence that the U.S. HIV epidemic increasingly is affecting populations with the highest rates of curable STIs, the CDC/HRSA Advisory Committee on HIV/AIDS and STI Prevention (CHAC) recommended the following:
Early detection and treatment of curable STIs should become a major, explicit component of comprehensive HIV prevention programs at national, state, and local levels;
In areas where STIs that facilitate HIV transmission are prevalent, screening and treatment programs should be expanded;
HIV testing should always be recommended for individuals who are diagnosed with or suspected to have an STI.
HIV and STI prevention programs in the United States, together with private and public sector partners, should take joint responsibility for implementing these strategies.
CHAC also notes that early detection and treatment of STIs should be only one component of a comprehensive HIV prevention program, which also must include a range of social, behavioral, and biomedical interventions.
Sexually Transmitted Infections (STIs), previously known as Sexually Transmitted Diseases (STDs) are infections and parasites that can be passed between partners during sexual contact: oral, anal, vaginal or skin to genital contact. There are 20 million new cases of STIs reported in the US each year and half those cases are in people ages 15-24. This is why getting STI screenings as soon as one becomes sexually active is key to maintaining sexual health for you and those you love. Because most STIs have no noticeable symptoms seeing your doctor and asking for STI testing as part of a yearly checkup is important for your general and sexual health.
Many have no noticeable symptoms, but some STIs can have serious reproductive health effects for both partners. The only way to protect yourself is to practice safer sex practices and to be tested regularly for STIs by your doctor or our staff and STD clinic NYC.