title: Marked differences in the prevalence of chloroquine resistance between urban and rural communities in Burkina Faso.
abstract: BACKGROUND
  Chloroquine (CQ) resistance has reached high levels in Africa in recent years. Little is known about variations of resistance between urban and rural areas.
  
  
  OBJECTIVE
  To compare the rates of in vivo resistance to CQ and the prevalences of the main molecular marker for CQ resistance among young children from urban and rural areas in Burkina Faso.
  
  
  METHODS
  The current analysis used the frame of a randomized controlled trial (ISRCTN27290841) on the combination CQ-methylene blue (MB) (n=177) compared to CQ alone (n=45) in young children with uncomplicated malaria. We examined clinical and parasitological failure rates as well as the prevalence of the Plasmodium falciparum chloroquine resistance transporter gene (pfcrt) T76 mutation.
  
  
  RESULTS
  Clinical and parasitological failure rates of CQ-MB differed significantly between urban (70%) and rural areas (29%, p<0.0001). Likewise, CQ failure rates were higher in the urban setting. Matching this pattern, pfcrt T76 was more frequently seen among parasite strains from urban areas (81%) when compared to rural ones (64%, p=0.01). In the presence of parasites exhibiting pfcrt T76, the odds of overall clinical failure were increased to 2.6-fold ([1.33, 5.16], p(LR)=0.005). CQ was detected at baseline in 21% and 2% of children from the urban and the rural study area, respectively (p(Chi)=0.002).
  
  
  CONCLUSIONS
  Even within circumscribed geographical areas, CQ efficacy can vary dramatically. The differences in the prevalence of pfcrt T76 and in CQ failure rates are probably explained by a higher drug pressure in the urban area compared to the rural study area. This finding has important implications for national malaria policies.
authors: Department of Tropical Hygiene and Public Health, Ruprecht-Karls-University, Heidelberg, Germany. peter.meissner@urz.uni-heidelberg.de
authors: Peter E
authors: PE
authors: Meissner
authors: Germain
authors: G
authors: Mandi
authors: Frank P
authors: FP
authors: Mockenhaupt
authors: Steffen
authors: S
authors: Witte
authors: Boubacar
authors: B
authors: Coulibaly
authors: Ulrich
authors: U
authors: Mansmann
authors: Claudia
authors: C
authors: Frey
authors: Heiko
authors: H
authors: Merkle
authors: Juergen
authors: J
authors: Burhenne
authors: Ingeborg
authors: I
authors: Walter-Sack
authors: Olaf
authors: O
authors: Müller
mesh_terms: D000818:Animals; D002050:Burkina Faso; D002675:Child, Preschool; D002738:Chloroquine / Q000494:pharmacology* / Q000627:therapeutic use; D004351:Drug Resistance / Q000235:genetics*; D006801:Humans; D007223:Infant; D016778:Malaria, Falciparum / Q000188:drug therapy / Q000469:parasitology*; D026901:Membrane Transport Proteins / Q000235:genetics; D010963:Plasmodium falciparum / Q000187:drug effects* / Q000302:isolation & purification; D017354:Point Mutation; D015800:Protozoan Proteins / Q000235:genetics; D012424:Rural Population; D016896:Treatment Outcome; D014505:Urban Population
chemical_list: D026901:Membrane Transport Proteins; C416369:PfCRT protein, Plasmodium falciparum; D015800:Protozoan Proteins; D002738:Chloroquine