In 2011, the journal Science named the discovery that HIV medication may not only treat the disease, but also lower a person’s risk of spreading it to an unaffected partner as the scientific breakthrough of the year. One of the keys to fighting HIV is determining how to prevent transmission, and in order to do that scientists are learning new things about how this sexually transmitted infection (STI) operates inside the body. For example, research published in the Journal of Infectious Diseases has found that the single most important factor in determining a person’s likelihood of transmitting HIV to their partner is their viral load. Furthermore, the study found that condoms reduce the risk of HIV transmission by 78 percent, highlighting the need for more to be done to promote safer sex.
“Our results underscore the importance of antiretroviral therapy, and, possibly, treatment of co-infections, to reduce plasma HIV-1 viral load in HIV-1 infected partners, and condom promotion, male circumcision and treatment of symptomatic sexually-transmitted infections for HIV-1 uninfected partners as potential interventions to reduce HIV-1 transmission,” the authors wrote. The study also showed that the risk of an HIV-positive man transmitting the disease to an unaffected woman is twice as high as the chances of a woman passing the infection to a man. According to researchers, this could be due to the fact that men traditionally have a higher viral count than women. Finally, the scientists noted that individuals who have genital herpes are more susceptible to getting the virus, due to the open sores that may be present on their genitals. Study authors are planning additional studies to determine what populations are at the highest risk of transmitting HIV.