HIV-1 transmission among injection drug users leads to novel recombinants circulating in southern China.

Injection drug use has been responsible for most HIV-1 transmission in Asia and has led to the generation and/or spreading of circulating recombinant CRF01_AE, CRF07_BC, and CRF08_BC, which are currently the predominant HIV-1 strains in China. Monitoring HIV-1 transmissions among injection drug users (IDUs) still provides critical information on HIV-1 prevalence and control. In the present study, we detected three HIV-1 sequences, BH048/057/066, from IDUs in Beihai city, Guangxi province, all of which share an extremely complex mosaic recombination pattern. CRF01_AE and CRF08_BC contributed to the rise of new recombinants, which contain CRF08_BC-derived env fragments with evidence of further evolution. Our data, combined with those of other studies, suggest that the BH048/057/066 recombinants represent early strains of a circulating recombinant form of HIV-1 in southern China. Information concerning such newly appearing variants is critical for both HIV-1 control and ongoing HIV-1 vaccine trials in Guangxi, China.