Topazian HM, Stoner MC, Edwards JK, et al. - As age disparity has been classified as ≥ 5 or ≥ 10 years in nearly all population-level research explicating positive correlations between age-disparate partnerships and HIV acquisition among adolescent girls and young women (AGYW), researchers here reported disparities in 1-year risk of HIV infection after exposure to sexual partner(s) of continuous age disparities. One-year risk of HIV infection at various age pairings was estimated using longitudinal data from the HPTN 068 randomized trial in South Africa. In 86% of 5351 age pairings, an older partner by reported by AGYW. The analysis revealed a greater effect of age differences between AGYW and their sexual partners on HIV-risk infection in younger compared with older AGYW. Key groups for HIV transmission prevention efforts could be identified via considering both the age of an AGYW and her sexual partners provides.