title: Prevalence and mutation patterns of HIV drug resistance from 2010 to 2011 among ART-failure individuals in the Yunnan Province, China.
abstract: BACKGROUND
  Assessing the prevalence of HIV-1 drug-resistance and the mutation patterns associated with resistance in the geographical regions implementing free antiretroviral therapy (ART) in China is necessary for preventing the spread of resistant strains and designing the regimens for the subsequent therapies with limited resources.
  
  
  METHODS
  Plasma samples in different cities/prefectures were collected at Yunnan Provincial Hospital of Infectious Disease from January 2010 to December 2011. Genotyping of drug-resistant individuals was conducted using an in-house assay on plasma samples. Viral load, CD4 T cell counts and demographic data were obtained from medical records and an administered questionnaire.
  
  
  RESULTS
  A total of 609 pol sequences (515 ART-failure and 94 therapy-naïve individuals) derived from 664 samples were obtained. The prevalence of drug-resistance was 45.1% in the ART-failure individuals. Of these, 26.8% harbored HIV strains dually resistant to nucleoside reverse transcriptase inhibitors and non-nucleoside reverse transcriptase inhibitors, and 14.8% harbored HIV strains resistant to only one drug category. Mutations such as M184V/I, K103N, V106A, Y181C and G190A were common among the ART-failure individuals, and the frequencies of M184V/I, K103N and V106A were 28.2%, 19.2%, and 22.1%, respectively. The percentages of individuals exhibiting intermediate or high-level resistance to 3TC, FTC, EFV and NVP drugs were 28.4%, 28.2%, 37.3%, and 37.5%, respectively. Factors such as ethnicity, transmission route, CD4 counts, viral load and the duration of ART were significantly correlated with development of drug resistance in the ART-failure individuals.
  
  
  CONCLUSIONS
  The high prevalence of HIV drug-resistance observed among the ART-failure individuals from 2010 to 2011 in Yunnan province should be of increasing concern in regions where the implementation of ART is widespread. Education about the risk factors associated with HIV drug resistance is important for preventing and controlling the spread of HIV drug-resistant strains.
authors.affiliation: Department of AIDS Research, State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China.
authors.forename: Hanping
authors.initials: H
authors.lastname: Li
authors.forename: Min
authors.initials: M
authors.lastname: Zhong
authors.forename: Wei
authors.initials: W
authors.lastname: Guo
authors.forename: Daomin
authors.initials: D
authors.lastname: Zhuang
authors.forename: Lin
authors.initials: L
authors.lastname: Li
authors.forename: Yongjian
authors.initials: Y
authors.lastname: Liu
authors.forename: Zuoyi
authors.initials: Z
authors.lastname: Bao
authors.forename: Siyang
authors.initials: S
authors.lastname: Liu
authors.forename: Xiaolin
authors.initials: X
authors.lastname: Wang
authors.forename: Tianyi
authors.initials: T
authors.lastname: Li
authors.forename: Shaomin
authors.initials: S
authors.lastname: Yang
authors.forename: Jingyun
authors.initials: J
authors.lastname: Li
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D019380:Anti-HIV Agents / Q000494:pharmacology / Q000627:therapeutic use; D023241:Antiretroviral Therapy, Highly Active; D002648:Child; D002675:Child, Preschool; D002681:China / Q000453:epidemiology; D024882:Drug Resistance, Viral / Q000235:genetics*; D005260:Female; D005838:Genotype; D005843:Geography; D015658:HIV Infections / Q000188:drug therapy / Q000453:epidemiology* / Q000821:virology; D015497:HIV-1 / Q000187:drug effects* / Q000235:genetics*; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D009154:Mutation; D015995:Prevalence; D012307:Risk Factors; D017211:Treatment Failure; D055815:Young Adult
chemical_list: D019380:Anti-HIV Agents