Molecular epidemiology of HIV-1 in Jilin province, northeastern China: emergence of a new CRF07_BC transmission cluster and intersubtype recombinants.

Objective: To investigate the HIV-1 molecular epidemiology among newly diagnosed HIV-1 infected persons living in the Jilin province of northeastern China.

Methods: Plasma samples from 189 newly diagnosed HIV-1 infected patients were collected between June 2010 and August 2011 from all nine cities of Jilin province. HIV-1 nucleotide sequences of gag P17-P24 and env C2-C4 gene regions were amplified using a multiplex RT-PCR method and sequenced. Phylogenetic and recombination analyses were used to determine the HIV-1 genotypes.

Results: Based on all sequences generated, the subtype/CFR distribution was as follows: CRF01_AE (58.1%), CRF07_BC (13.2%), subtype B' (13.2%), recombinant viruses (8.1%), subtype B (3.7%), CRF02_AG (2.9%), subtype C (0.7%). In addition to finding CRF01_AE strains from previously reported transmission clusters 1, 4 and 5, a new transmission cluster was described within the CRF07_BC radiation. Among 11 different recombinants identified, 10 contained portions of gene regions from the CRF01_AE lineage. CRF02_AG was found to form a transmission cluster of 4 in local Jilin residents.

Conclusions: Our study presents a molecular epidemiologic investigation describing the complex structure of HIV-1 strains co-circulating in Jilin province. The results highlight the critical importance of continuous monitoring of HIV-infections, along with detailed socio-demographic data, in order to design appropriate prevention measures to limit the spread of new HIV infections.