title: HIV-1 genetic diversity and its distribution characteristics among newly diagnosed HIV-1 individuals in Hebei province, China.
abstract: BACKGROUND
  Since the first HIV-1 case in 1989, Hebei province has presented a clearly rising trend of HIV-1 prevalence, and HIV-1 genetic diversity has become the vital barrier to HIV prevention and control in this area. To obtain detailed information of HIV-1 spread in different populations and in different areas of Hebei, a cross-sectional HIV-1 molecular epidemiological investigation was performed across the province.
  
  
  METHODS
  Blood samples of 154 newly diagnosed HIV-1 individuals were collected from ten prefectures in Hebei using stratified sampling. Partial gag and env genes were amplified and sequenced. HIV-1 genotypes were identified by phylogenetic tree analyses.
  
  
  RESULTS
  Among the 139 subjects genotyped, six HIV-1 subtypes were identified successfully, including subtype B (41.0 %), CRF01_AE (40.3 %), CRF07_BC (11.5 %), CRF08_BC (4.3 %), unique recombinant forms (URFs) (1.4 %) and subtype C (1.4 %). Subtype B was identified as the most frequent subtype. Two URF recombination patterns were the same as CRF01_AE/B. HIV-1 genotype distribution showed a significant statistical difference in different demographic characteristics, such as source (P < 0.05), occupation (P < 0.05) and ethnicity (P < 0.05). The distributions of subtype B (P < 0.05), CRF01_AE (P < 0.05), CRF07_BC (P < 0.05) and subtype C (P < 0.05) showed significant differences in all ten prefectures, and the distributions of all six subtypes were significantly different in Shijiazhuang (P < 0.05) and Xingtai (P < 0.05), but not in other prefectures (P > 0.05). The differences in HIV-1 genotype distribution were closely associated with transmission routes. Particularly, all six subtype strains were found in heterosexuals, showing that HIV-1 has spread from the high-risk populations to the general populations in Hebei, China. In addition, CRF01_AE instead of subtype B has become the major strain of HIV-1 infection among homosexuals.
  
  
  CONCLUSIONS
  Our study revealed HIV-1 evolution and genotype distribution by investigating newly diagnosed HIV-1 individuals in Hebei, China. This study provides important information to enhance the strategic plan for HIV prevention and control in China.
authors.affiliation: Hebei Provincial Center for Disease Control and Prevention, 97 Huaian East Rd, Yuhua District, 050021 Shjiazhuang, People's Republic of China.
authors.forename: Xinli
authors.initials: X
authors.lastname: Lu
authors.affiliation: Hebei Provincial Center for Disease Control and Prevention, 97 Huaian East Rd, Yuhua District, 050021 Shjiazhuang, People's Republic of China.
authors.forename: Cuiying
authors.initials: C
authors.lastname: Zhao
authors.affiliation: Hebei Provincial Center for Disease Control and Prevention, 97 Huaian East Rd, Yuhua District, 050021 Shjiazhuang, People's Republic of China.
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.affiliation: College of Chemistry and Environmental Science, Hebei University, 180 Wusi East Rd, 071002 Baoding, People's Republic of China.
authors.forename: Chenxi
authors.initials: C
authors.lastname: Nie
authors.affiliation: Hebei Provincial Center for Disease Control and Prevention, 97 Huaian East Rd, Yuhua District, 050021 Shjiazhuang, People's Republic of China.
authors.forename: Yuqi
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Hebei Provincial Center for Disease Control and Prevention, 97 Huaian East Rd, Yuhua District, 050021 Shjiazhuang, People's Republic of China.
authors.forename: Hongru
authors.initials: H
authors.lastname: Zhao
authors.affiliation: Hebei Provincial Center for Disease Control and Prevention, 97 Huaian East Rd, Yuhua District, 050021 Shjiazhuang, People's Republic of China.
authors.forename: Suliang
authors.initials: S
authors.lastname: Chen
authors.affiliation: Hebei Provincial Center for Disease Control and Prevention, 97 Huaian East Rd, Yuhua District, 050021 Shjiazhuang, People's Republic of China.
authors.forename: Ze
authors.initials: Z
authors.lastname: Cui
mesh_terms: D000293:Adolescent; D000328:Adult; D002681:China / Q000453:epidemiology; D003430:Cross-Sectional Studies; D005260:Female; D015686:Gene Products, env / Q000235:genetics; D015683:Gene Products, gag / Q000235:genetics; D014644:Genetic Variation / Q000235:genetics; D005838:Genotype; D015658:HIV Infections / Q000453:epidemiology / Q000235:genetics*; D015497:HIV-1 / Q000235:genetics*; D006801:Humans; D008297:Male; D010802:Phylogeny; D017422:Sequence Analysis, DNA; D055815:Young Adult
chemical_list: D015686:Gene Products, env; D015683:Gene Products, gag
keywords: China; Distribution; Genetic diversity; HIV-1; Phylogeny; Transmission