title: Regional variation in Ascaris lumbricoides and Trichuris trichiura infections by age cohort and sex: effects of market integration among the indigenous Shuar of Amazonian Ecuador.
abstract: BACKGROUND
  Soil-transmitted helminth (STH) infection peaks during childhood and varies by sex. The impact of market integration (MI) (increasing production for and consumption from a market-based economy) on these infection patterns, however, is unclear. In this study, STH infection is examined by sex and age among indigenous Shuar inhabiting two regions of Amazonian Ecuador: (1) the modestly market-integrated Upano Valley (UV) and (2) the more traditional Cross-Cutucú (CC) region.
  
  
  METHODS
  Kato-Katz fecal smears were examined for parasite presence and infection intensity. Factorial ANOVAs and post hoc simple effects analyses were performed by sex to compare infection intensity between regions and age categories (infant/child, juvenile/adolescent, adult).
  
  
  RESULTS
  Significant age and regional differences in Ascaris lumbricoides and Trichuris trichiura infection were detected. Overall, infants/children and juveniles/adolescents displayed higher parasite loads than adults. CC females exhibited higher A. lumbricoides loads than UV females, while the opposite pattern was observed for T. trichiura infection in males.
  
  
  CONCLUSIONS
  Regional infection patterns varied by sex and parasite species, perhaps due to MI-linked environmental and lifestyle changes. These results have public health implications for the identification of individuals at risk for infection and contribute to ongoing efforts to track changes and alleviate STH infection in indigenous populations undergoing MI.
authors.affiliation: Department of Anthropology, University of Oregon, Eugene, Oregon, 97403, USA. tgildner@uoregon.edu.
authors.forename: Theresa E
authors.initials: TE
authors.lastname: Gildner
authors.affiliation: Department of Anthropology, University of Colorado, Colorado Springs, CO, USA.
authors.forename: Tara J
authors.initials: TJ
authors.lastname: Cepon-Robins
authors.affiliation: Department of Anthropology, University of Oregon, Eugene, Oregon, 97403, USA.
authors.forename: Melissa A
authors.initials: MA
authors.lastname: Liebert
authors.affiliation: Department of Anthropology, Hunter College (CUNY), New York City, NY, USA.
authors.forename: Samuel S
authors.initials: SS
authors.lastname: Urlacher
authors.affiliation: Queens College (CUNY), Flushing, NY, USA.
authors.forename: Felicia C
authors.initials: FC
authors.lastname: Madimenos
authors.affiliation: Department of Anthropology, University of Oregon, Eugene, Oregon, 97403, USA.
authors.forename: J Josh
authors.initials: JJ
authors.lastname: Snodgrass
authors.affiliation: Department of Anthropology, University of Oregon, Eugene, Oregon, 97403, USA.
authors.forename: Lawrence S
authors.initials: LS
authors.lastname: Sugiyama
mesh_terms: D000293:Adolescent; D000328:Adult; D000375:Aging; D000818:Animals; D001196:Ascariasis / Q000453:epidemiology* / Q000469:parasitology; D017164:Ascaris lumbricoides; D002648:Child; D002675:Child, Preschool; D003710:Demography; D004484:Ecuador / Q000453:epidemiology; D005243:Feces / Q000469:parasitology; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D010270:Parasite Egg Count; D044382:Population Groups; D011159:Population Surveillance; D012737:Sex Factors; D014257:Trichuriasis / Q000453:epidemiology* / Q000469:parasitology; D014258:Trichuris; D055815:Young Adult
keywords: Indigenous health; Lifestyle change; Parasite infection