Timing and source of subtype-C HIV-1 superinfection in the newly infected partner of Zambian couples with disparate viruses

摘要

BackgroundHIV-1 superinfection occurs at varying frequencies in different at risk populations. Though seroincidence is decreased, in the negative partner of HIV-discordant couples after joint testing and counseling in the Zambia Emory HIV Research Project (ZEHRP) cohort, the annual infection rate remains relatively high at 7-8%. Based on sequencing within the gp41 region of each partner's virus, 24% of new infections between 2004 and 2008 were the result of transmission from a non-spousal partner. Since these seroconvertors and their spouses have disparate epidemiologically-unlinked viruses, there is a risk of superinfection within the marriage. We have, therefore, investigated the incidence and viral origin of superinfection in these couples.