Identification of Subtype B, Multiple Circulating Recombinant Forms and Unique Recombinants of HIV Type 1 in an MSM Cohort in China

Abstract

To study HIV-1 genetic diversity among HIV-positive men who have sex with men (MSM) in China, a cohort consisting of HIV-positive MSM was established in 2005 and was monitored every 2 years. In 2007, 44 HIVpositiveMSM subjects were genotyped, and the results showed HIV-1 subtype B decreased from 77.5% to41.9%, but non-B subtypes increased rapidly represented by CRF01_AE from 3.7% to 30.2% compared to 2005.In addition, one case of CRF07_BC was first identified in this population, which mainly circulated among HIV-1-infected injection drug users (IDUs) in China. There were 11 unique recombinant forms (URFs) consisting ofa recombination of CRF01_AE with subtype B or CRF07_BC. The subtype-specific phylogenic tree analysis showed that the genetic distance within subtype B group viruses was larger than the genetic distance within the CRF01_AE group (p 0.001). Of the identified viruses in the Chinese MSM population, over 80% of subtype B viruses might originate from the United States and Brazil, and over 85% of the CRF01_AE viruses mightoriginate from Thailand. In addition, epidemic study data showed that some of the HIV-1-infected MSM had foreign sexual partners (13.6%) and heterosexual activities (43.2%). The patients infected with HIV-1 URF viruses had more heterosexual encounters (54.5%) and more sexual partners (72.7%) compared to those infected with subtype B (44.4%; 33.3%) and CRF01_AE (23.1%; 69.2%) viruses. Taken together, we suspected that the genetic complexity of HIV-1 viruses identified in Chinese MSM populations was more likely a result of multiple introductions of viruses from the general population infected with HIV-1 through IDUs or heterosexual transmission.

Emergence in Japan of an HIV-1 Variant Associated with Transmission among Men Who Have Sex with Men (MSM) in China: First Indication of the International Dissemination of the Chinese MSM Lineage

“…In contrast, China recently witnessed a dramatic shift in genotype distribution from subtype B to CRF01_AE among MSM. (16)(17)(18). The rise of CRF01_AE infections among MSM has also been reported in other regions in China, including Liaoning (northeastern) (19), Jiangsu (eastern) provinces (10), Shijiazhuang, the capital city of Hebei (north-central) (20), and Zhengzhou, the capital city of Henan (Central) (21).…”

HIV Epidemic in Asia: Implications for HIV Vaccine and Other Prevention Trials

“…Recently, however, MSM is the risk group associated with the most rapid increases in HIV infections within China, and studies note HIV-1 strains of different subtypes and CRFs. [38][39][40][41][42] In cities in northern China CRF01_AE infection in MSM is more common than subtype B, 24,[43][44][45] with similar trends in Beijing, Fujian, Guizho, Guandong, Guanxi, Hebei, Hong Kong, Hunan, Jiangsu, Jianxi, Shanghai, and Yunnan. CRF07_BC has recently been identified in young MSM and in some cities exceeds the prevalence of CRF01_AE infection (unpublished data).…”

Reconstituting the Epidemic History of HIV Strain CRF01_AE among Men Who Have Sex with Men (MSM) in Liaoning, Northeastern China: Implications for the Expanding Epidemic among MSM in China

“…It is well known that subtype B=, CRF07_BC, CRF08_BC, and CRF01_AE are the major HIV-1 genotypes associated with particular risk populations in China (2,25,26,31). Reports about China in recent years showed that multiple HIV-1 subtypes, including subtype B, CRF01_AE, and CRF07_BC, were coepidemic in the population of MSM (18,32,33).…”

“…CRF01_AE, which was the dominant strain in the sexual-risk population (34), seems to have played a more and more important role within the population of MSM. The percentage of CRF01_AE has been increasing recently and has exceeded that of subtype B, the previously dominant strain, in different cities (10,14,18,31,32). In addition, Chen et al reported that the time of the epidemic of the most recent common ancestor (tMRCA) of CRF01_AE in Hong Kong was in the mid1990s (3).…”