Aspirin is used to reduce fever, relieve mild to moderate pain and to prevent blood clots in patients with heart disease. Now, it could also be used to prevent HIV transmission. Researchers tested the effect of acetylsalicylic acid (Aspirin) and other anti-inflammatory drugs on HIV target cells in a group of Kenyan women who were at low risk of HIV infection. Transmission of the virus requires a susceptible target cell. “Activated immune cells are more susceptible to HIV infection than resting cells. Inflammation brings activated HIV target cells to the female genital tract,” noted the study. The study quantified HIV target cells in the blood and vagina of 37 Kenyan women before and after taking Aspirin for up to six weeks. Participants were given the same daily low dose of Aspirin that is commonly used for long-term prevention of cardiovascular disease. Among the anti-inflammatory drugs tested, Aspirin was the most effective. It reduced the number of HIV target cells in the female genital tract by 35 per cent. Trial The reduced number of HIV target cells in the women who took Aspirin approached the level found in Kenyan women at high risk of HIV infection, who have remained uninfected for many years, in part because they have very little inflammation in their blood and genital tract. Aspirin seemed to increase the structural integrity of the skin in the vagina, which could also prevent HIV infection by further restricting HIV’s access to more target cells in the blood. “Further research is needed to confirm our results and test whether this level of target cell reduction will actually prevent HIV infection,” said lead author Dr Keith Fowke. “If so, this could be a strategy for HIV prevention that is not only inexpensive, but also easily accessed.” The next step will be a clinical trial to test whether Aspirin can reduce inflammation in women using PrEP (anti-HIV drugs used for prevention) and thereby reduce infections in women at high risk, such as female sex workers. If the scientists can demonstrate this, Aspirin would be the first drug that targets the host, rather than the virus, to prevent HIV. Agencies