title: Genotypes and transmitted drug resistance among treatment-naive HIV-1-infected patients in a northwestern province, China: trends from 2003 to 2013.
abstract: BACKGROUND
  Transmitted drug resistance (TDR) reduces the efficacy of initial antiretroviral treatment and has become a public health concern. Little information is available regarding the genetic diversity of HIV-1 and the prevalence of TDR among treatment-naïve patients in a northwestern province of China since the implementation of national free antiretroviral therapy (ART).
  
  
  METHODS
  Blood samples from 372 HIV-1 treatment-naive patients were collected between 2003 and 2013 in Shaanxi province. Viral RNA was extracted for nested PCR, and phylogenetic reconstruction and recombination analyses were performed to characterize patterns of the HIV-1 subtypes. Genotypic drug resistance testing was performed using an in-house assay to determine trends in the prevalence of HIV-1 transmitted drug resistance.
  
  
  RESULTS
  Multiple genotypes were identified among the patients in Shaanxi, including B (25.0%), C (0.3%), G (0.3%), and CRF01_AE (39.2%), CRF07_BC (32.7%), CRF08_BC (0.8%), CRF55_01B (1.1%), and URFs (0.6%). The subtypes were associated with the transmission routes (χ2 = 77.113, p < 0.01). In this study, a low baseline CD4+ T cell count and a high viral load were found among CRF01_AE-infected patients compared with patients who were infected with non-CRF01_AE (p<0.01) through sexual transmission; however, the CRF01_AE subtype was not associated with a low baseline CD4+ T cell count or a high viral load in Chinese patients infected through blood transmission (p = 0.249). The overall TDR rate in this population was 4.4% between 2003 and 2013. A univariate logistic regression model revealed that a low CD4 T cell count (≤ 100 cells/µL) was associated with the development of drug-resistant strains.
  
  
  CONCLUSIONS
  Our work revealed diverse HIV-1 subtype distributions in Shaanxi province. We identified a low and stable TDR time trend among ART-naive patients. These findings enhance our understanding of HIV-1 genetic diversity and provide some guidelines for the improvement and implementation of a comprehensive public health strategy of HIV-1 TDR prevention.
authors.affiliation: Department of Infectious Diseases, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China.
authors.forename: Ke
authors.initials: K
authors.lastname: Zhao
authors.affiliation: Department of Infectious Diseases, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China.
authors.forename: Wenzhen
authors.initials: W
authors.lastname: Kang
authors.affiliation: Department of Endocrinology, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China.
authors.forename: Qingquan
authors.initials: Q
authors.lastname: Liu
authors.affiliation: Department of Infectious Diseases, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Infectious Diseases, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Liu
authors.affiliation: Department of Infectious Diseases, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Jiang
authors.affiliation: Department of Infectious Diseases, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhuang
authors.affiliation: Department of Infectious Diseases, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China.
authors.forename: Zisheng
authors.initials: Z
authors.lastname: Guo
authors.affiliation: Department of Infectious Diseases, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China.
authors.forename: Zhuoran
authors.initials: Z
authors.lastname: Yu
authors.affiliation: Department of Infectious Diseases, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China.
authors.forename: Xinhong
authors.initials: X
authors.lastname: Li
authors.affiliation: Department of Infectious Diseases, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China.
authors.forename: Chunfu
authors.initials: C
authors.lastname: Wang
authors.affiliation: Department of Infectious Diseases, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China.
authors.forename: Na
authors.initials: N
authors.lastname: Yao
authors.affiliation: Department of Infectious Diseases, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China.
authors.forename: Yongtao
authors.initials: Y
authors.lastname: Sun
mesh_terms: D000328:Adult; D044966:Anti-Retroviral Agents / Q000627:therapeutic use; D015496:CD4-Positive T-Lymphocytes / Q000821:virology; D002681:China; D024882:Drug Resistance, Viral / Q000235:genetics*; D005260:Female; D005838:Genotype; D015658:HIV Infections / Q000188:drug therapy / Q000235:genetics*; D015497:HIV-1 / Q000235:genetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012367:RNA, Viral; D055815:Young Adult
chemical_list: D044966:Anti-Retroviral Agents; D012367:RNA, Viral