title: Geographic correlation between tapeworm carriers and heavily infected cysticercotic pigs.
abstract: BACKGROUND
  Neurocysticercosis is a leading cause of preventable epilepsy in the developing world. Sustainable community-based interventions are urgently needed to control transmission of the causative parasite, Taenia solium. We examined the geospatial relationship between live pigs with visible cysticercotic cysts on their tongues and humans with adult intestinal tapeworm infection (taeniasis) in a rural village in northern Peru. The objective was to determine whether tongue-positive pigs could indicate high-risk geographic foci for taeniasis to guide targeted screening efforts. This approach could offer significant benefit compared to mass intervention.
  
  
  METHODS
  We recorded geographic coordinates of all village houses, collected stool samples from all consenting villagers, and collected blood and examined tongues of all village pigs. Stool samples were processed by enzyme-linked immunosorbent assay (ELISA) for presence of Taenia sp. coproantigens indicative of active taeniasis; serum was processed by enzyme-linked immunoelectrotransfer blot for antibodies against T. solium cysticercosis (EITB LLGP) and T. solium taeniasis (EITB rES33).
  
  
  RESULTS
  Of 548 pigs, 256 (46.7%) were positive for antibodies against cysticercosis on EITB LLGP. Of 402 fecal samples, 6 (1.5%) were positive for the presence of Taenia sp. coproantigens. The proportion of coproantigen-positive individuals differed significantly between residents living within 100-meters of a tongue-positive pig (4/79, 5.1%) and residents living >100 meters from a tongue-positive pig (2/323, 0.6%) (p = 0.02). The prevalence of taeniasis was >8 times higher among residents living within 100 meters of a tongue-positive pig compared to residents living outside this range (adjusted PR 8.1, 95% CI 1.4-47.0).
  
  
  CONCLUSIONS
  Tongue-positive pigs in endemic communities can indicate geospatial foci in which the risk for taeniasis is increased. Targeted screening or presumptive treatment for taeniasis within these high-risk foci may be an effective and practical control intervention for rural endemic areas.
authors.affiliation: Department of Public Health and Preventive Medicine, Oregon Health and Science University, Portland, Oregon, United States of America. oneals@ohsu.edu
authors.forename: Seth E
authors.initials: SE
authors.lastname: O'Neal
authors.forename: Luz M
authors.initials: LM
authors.lastname: Moyano
authors.forename: Viterbo
authors.initials: V
authors.lastname: Ayvar
authors.forename: Guillermo
authors.initials: G
authors.lastname: Gonzalvez
authors.forename: Andre
authors.initials: A
authors.lastname: Diaz
authors.forename: Silvia
authors.initials: S
authors.lastname: Rodriguez
authors.forename: Patricia P
authors.initials: PP
authors.lastname: Wilkins
authors.forename: Victor C W
authors.initials: VC
authors.lastname: Tsang
authors.forename: Robert H
authors.initials: RH
authors.lastname: Gilman
authors.forename: Hector H
authors.initials: HH
authors.lastname: Garcia
authors.forename: Armando E
authors.initials: AE
authors.lastname: Gonzalez
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D000909:Antibodies, Helminth / Q000097:blood; D002590:Cestode Infections / Q000453:epidemiology* / Q000662:veterinary*; D002648:Child; D002675:Child, Preschool; D005243:Feces / Q000469:parasitology; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D010568:Peru / Q000453:epidemiology; D012424:Rural Population; D013552:Swine; D013553:Swine Diseases / Q000453:epidemiology* / Q000469:parasitology*; D041201:Taenia solium / Q000302:isolation & purification*; D014059:Tongue / Q000473:pathology; D019371:Topography, Medical; D055815:Young Adult
chemical_list: D000909:Antibodies, Helminth