title: Prevalence of HIV-1 drug resistance in treated patients with viral load >50 copies/mL in 2009: a French nationwide study.
abstract: BACKGROUND
  Surveillance of HIV-1 drug resistance in treated patients with plasma viral load (VL) >50 copies/mL.
  
  
  METHODS
  The protease and reverse transcriptase (RT) genes were systematically sequenced in samples from 756 patients with VL >50 copies/mL in 2009. The genotyping results were interpreted for each antiretroviral drug (ARV) by using the ANRS algorithm v21. Weighted analyses were used to derive representative estimates of percentages of patients. Prevalence rates were compared with those obtained in 2004 among patients with VL >1000 copies/mL.
  
  
  RESULTS
  Sequences were obtained for 506 patients. Sequencing was successful in 45%, 80% and 96% of samples with VL of 51-500, 501-1000 and >1000 copies/mL, respectively. Resistance or possible resistance to at least one ARV was observed in 59% of samples. Overall, 0.9% of samples contained viruses resistant to all drugs belonging to at least three drug classes. All resistance prevalence rates were significantly lower in 2009 than in 2004.
  
  
  CONCLUSIONS
  In France, where 86% of patients were receiving combination antiretroviral therapy in 2009, only 15.0% of patients had a VL >50 copies/mL, suggesting that only 8.9% of treated patients could potentially transmit resistant viruses. Only 0.08% of patients harboured viruses fully resistant to at least three antiretroviral drug classes. Further studies are needed to determine whether resistance continues to decline over time.
authors: INSERM, U 943, Paris, France. klassoumou@ccde.chups.jussieu.fr
authors: Lambert
authors: L
authors: Assoumou
authors: Diane
authors: D
authors: Descamps
authors: Sabine
authors: S
authors: Yerly
authors: Georges
authors: G
authors: Dos Santos
authors: Anne-Geneviève
authors: AG
authors: Marcelin
authors: Constance
authors: C
authors: Delaugerre
authors: Laurence
authors: L
authors: Morand-Joubert
authors: Annick
authors: A
authors: Ruffault
authors: Jacques
authors: J
authors: Izopet
authors: Jean-Christophe
authors: JC
authors: Plantier
authors: Sophie
authors: S
authors: Pakianather
authors: Brigitte
authors: B
authors: Montes
authors: Marie-Laure
authors: ML
authors: Chaix
authors: Marc
authors: M
authors: Wirden
authors: Dominique
authors: D
authors: Costagliola
authors: Bernard
authors: B
authors: Masquelier
mesh_terms: D000368:Aged; D000595:Amino Acid Sequence; D019380:Anti-HIV Agents / Q000627:therapeutic use; D023241:Antiretroviral Therapy, Highly Active; D003625:Data Collection; D024882:Drug Resistance, Viral; D005260:Female; D005602:France / Q000453:epidemiology; D005838:Genotype; D015658:HIV Infections / Q000453:epidemiology* / Q000821:virology*; D015497:HIV-1 / Q000187:drug effects / Q000235:genetics; D006306:Health Surveys; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012367:RNA, Viral / Q000097:blood; D017211:Treatment Failure; D019562:Viral Load
chemical_list: D019380:Anti-HIV Agents; D012367:RNA, Viral
keywords: HIV-1 drug resistance; antiretroviral therapy; epidemiology; multidrug resistance; plasma HIV RNA; virological failure