title: Re-imagining malaria: heterogeneity of human and mosquito behaviour in relation to residual malaria transmission in Cambodia.
abstract: BACKGROUND
  In certain regions in Southeast Asia, where malaria is reduced to forested regions populated by ethnic minorities dependent on slash-and-burn agriculture, malaria vector populations have developed a propensity to feed early and outdoors, limiting the effectiveness of long-lasting insecticide-treated nets (LLIN) and indoor residual spraying (IRS). The interplay between heterogeneous human, as well as mosquito behaviour, radically challenges malaria control in such residual transmission contexts. This study examines human behavioural patterns in relation to the vector behaviour.
  
  
  METHODS
  The anthropological research used a sequential mixed-methods study design in which quantitative survey research methods were used to complement findings from qualitative ethnographic research. The qualitative research existed of in-depth interviews and participant observation. For the entomological research, indoor and outdoor human landing collections were performed. All research was conducted in selected villages in Ratanakiri province, Cambodia.
  
  
  RESULTS
  Variability in human behaviour resulted in variable exposure to outdoor and early biting vectors: (i) indigenous people were found to commute between farms in the forest, where malaria exposure is higher, and village homes; (ii) the indoor/outdoor biting distinction was less clear in forest housing often completely or partly open to the outside; (iii) reported sleeping times varied according to the context of economic activities, impacting on the proportion of infections that could be accounted for by early or nighttime biting; (iv) protection by LLINs may not be as high as self-reported survey data indicate, as observations showed around 40% (non-treated) market net use while (v) unprotected evening resting and deep forest activities impacted further on the suboptimal use of LLINs.
  
  
  CONCLUSIONS
  The heterogeneity of human behaviour and the variation of vector densities and biting behaviours may lead to a considerable proportion of exposure occurring during times that people are assumed to be protected by the distributed LLINs. Additional efforts in improving LLIN use during times when people are resting in the evening and during the night might still have an impact on further reducing malaria transmission in Cambodia.
authors.affiliation: Institute of Tropical Medicine, Antwerp, Belgium. cgryseels@itg.be.|AISSR, University of Amsterdam, Amsterdam, The Netherlands. cgryseels@itg.be.
authors.forename: Charlotte
authors.initials: C
authors.lastname: Gryseels
authors.affiliation: Institute of Tropical Medicine, Antwerp, Belgium. ldurnez@itg.be.
authors.forename: Lies
authors.initials: L
authors.lastname: Durnez
authors.affiliation: AISSR, University of Amsterdam, Amsterdam, The Netherlands. rgerretswork@outlook.com.
authors.forename: René
authors.initials: R
authors.lastname: Gerrets
authors.affiliation: National Center for Parasitology, Entomology and Malaria Control, Phnom Penh, Cambodia. uk.sambunny@yahoo.com.
authors.forename: Sambunny
authors.initials: S
authors.lastname: Uk
authors.affiliation: National Center for Parasitology, Entomology and Malaria Control, Phnom Penh, Cambodia. suon.sokha@gmail.com.
authors.forename: Sokha
authors.initials: S
authors.lastname: Suon
authors.affiliation: National Center for Parasitology, Entomology and Malaria Control, Phnom Penh, Cambodia. setsrun@gmail.com.
authors.forename: Srun
authors.initials: S
authors.lastname: Set
authors.affiliation: National Center for Parasitology, Entomology and Malaria Control, Phnom Penh, Cambodia. pisen_phoeuk@yahoo.com.
authors.forename: Pisen
authors.initials: P
authors.lastname: Phoeuk
authors.affiliation: Institute of Tropical Medicine, Antwerp, Belgium. vsluydts@itg.be.
authors.forename: Vincent
authors.initials: V
authors.lastname: Sluydts
authors.affiliation: National Center for Parasitology, Entomology and Malaria Control, Phnom Penh, Cambodia. hengsomony@gmail.com.
authors.forename: Somony
authors.initials: S
authors.lastname: Heng
authors.affiliation: National Center for Parasitology, Entomology and Malaria Control, Phnom Penh, Cambodia. thosochantha@gmail.com.
authors.forename: Tho
authors.initials: T
authors.lastname: Sochantha
authors.affiliation: Institute of Tropical Medicine, Antwerp, Belgium. mcoosemans@itg.be.|University of Antwerp, Antwerp, Belgium. mcoosemans@itg.be.
authors.forename: Marc
authors.initials: M
authors.lastname: Coosemans
authors.affiliation: Institute of Tropical Medicine, Antwerp, Belgium. kpeeters@itg.be.|Partners for Applied Social Sciences (PASS) International, Tessenderlo, Belgium. kpeeters@itg.be.|School of International Health Development, Nagasaki University, Nagasaki, Japan. kpeeters@itg.be.
authors.forename: Koen
authors.initials: K
authors.lastname: Peeters Grietens
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000383:Agriculture; D000818:Animals; D002160:Cambodia; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D009033:Culicidae / Q000502:physiology*; D005247:Feeding Behavior; D005260:Female; D065928:Forests; D006798:Housing; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007303:Insect Vectors / Q000502:physiology*; D057148:Insecticide-Treated Bednets; D008288:Malaria / Q000469:parasitology / Q000517:prevention & control / Q000635:transmission*; D008297:Male; D008875:Middle Aged; D009032:Mosquito Control / Q000295:instrumentation / Q000379:methods*; D012890:Sleep; D055815:Young Adult