“Upbeat new HIV prevention findings presented last week at an international AIDS conference held in Rome have complicated attempts by the World Health Organization (WHO) to draft much-anticipated guidelines for heterosexual couples in which one partner is infected,” ScienceInsider reports.

WHO had planned to release guidelines for discordant couples, which it had been working on for months, at the conference, but pulled them at the last minute after consulting “a range of partners,” including UNAIDS and the Bill & Melinda Gates Foundation, according to Gottfried Hirnschall, head of the WHO HIV/AIDS department, the news service notes. “In particular, the partners had concerns about both the language in the document and its lack of inclusion of” findings from the HPTN 052 and Partners PrEP clinical trials, ScienceInsider writes (Cohen, 7/25).