Researchers at the Johns Hopkins Bloomberg School of Public Health are making strides toward preventing the spread of HIV/AIDS. In the first large-scale study of HIV superinfection in a general heterosexual population, researchers examined the rate of superinfection among a community of sub-Saharan adults. HIV superinfection occurs when an HIV-infected individual acquires a new viral strain that is phylogenetically different from all other detectable viral strains. Superinfection can have detrimental clinical effects, accelerated disease progression, and increased HIV drug resistance even among individuals who were previously controlling their HIV infection.