title: Hunting, swimming, and worshiping: human cultural practices illuminate the blood meal sources of cave dwelling Chagas vectors (Triatoma dimidiata) in Guatemala and Belize.
abstract: BACKGROUND
  Triatoma dimidiata, currently the major Central American vector of Trypanosoma cruzi, the parasite that causes Chagas disease, inhabits caves throughout the region. This research investigates the possibility that cave dwelling T. dimidiata might transmit the parasite to humans and links the blood meal sources of cave vectors to cultural practices that differ among locations.
  
  
  RESULTS
  We determined the blood meal sources of twenty-four T. dimidiata collected from two locations in Guatemala and one in Belize where human interactions with the caves differ. Blood meal sources were determined by cloning and sequencing PCR products amplified from DNA extracted from the vector abdomen using primers specific for the vertebrate 12S mitochondrial gene. The blood meal sources were inferred by ≥ 99% identity with published sequences. We found 70% of cave-collected T. dimidiata positive for human DNA. The vectors had fed on 10 additional vertebrates with a variety of relationships to humans, including companion animal (dog), food animals (pig, sheep/goat), wild animals (duck, two bat, two opossum species) and commensal animals (mouse, rat). Vectors from all locations fed on humans and commensal animals. The blood meal sources differ among locations, as well as the likelihood of feeding on dog and food animals. Vectors from one location were tested for T. cruzi infection, and 30% (3/10) tested positive, including two positive for human blood meals.
  
  
  CONCLUSIONS
  Cave dwelling Chagas disease vectors feed on humans and commensal animals as well as dog, food animals and wild animals. Blood meal sources were related to human uses of the caves. We caution that just as T. dimidiata in caves may pose an epidemiological risk, there may be other situations where risk is thought to be minimal, but is not.
authors.affiliation: Department of Biology, College of Arts and Sciences, University of Vermont, Burlington, Vermont, United States of America.
authors.forename: Lori
authors.initials: L
authors.lastname: Stevens
authors.affiliation: Escuela de Biologia, Universidad de San Carlos de Guatemala, Ciudad de Guatemala, Guatemala.
authors.forename: M Carlota
authors.initials: MC
authors.lastname: Monroy
authors.affiliation: Escuela de Biologia, Universidad de San Carlos de Guatemala, Ciudad de Guatemala, Guatemala.
authors.forename: Antonieta Guadalupe
authors.initials: AG
authors.lastname: Rodas
authors.affiliation: Department of Biological Sciences, Loyola University New Orleans, New Orleans, Louisiana, United States of America.
authors.forename: Patricia L
authors.initials: PL
authors.lastname: Dorn
mesh_terms: D000818:Animals; D001483:Base Sequence; D001531:Belize; D059552:Caves; D014355:Chagas Disease / Q000453:epidemiology / Q000469:parasitology / Q000635:transmission; D003469:Culture; D004247:DNA / Q000235:genetics; D017931:DNA Primers / Q000235:genetics; D004199:Disease Vectors; D006166:Guatemala; D006801:Humans; D007303:Insect Vectors / Q000469:parasitology*; D016133:Polymerase Chain Reaction; D013550:Swimming; D014224:Triatoma / Q000469:parasitology / Q000502:physiology*; D014349:Trypanosoma cruzi / Q000235:genetics
chemical_list: D017931:DNA Primers; D004247:DNA