title: A history of chagas disease transmission, control, and re-emergence in peri-rural La Joya, Peru.
abstract: BACKGROUND
  The history of Chagas disease control in Peru and many other nations is marked by scattered and poorly documented vector control campaigns. The complexities of human migration and sporadic control campaigns complicate evaluation of the burden of Chagas disease and dynamics of Trypanosoma cruzi transmission.
  
  
  RESULTS
  We conducted a cross-sectional serological and entomological study to evaluate temporal and spatial patterns of T. cruzi transmission in a peri-rural region of La Joya, Peru. We use a multivariate catalytic model and Bayesian methods to estimate incidence of infection over time and thereby elucidate the complex history of transmission in the area. Of 1,333 study participants, 101 (7.6%; 95% CI: 6.2-9.0%) were confirmed T. cruzi seropositive. Spatial clustering of parasitic infection was found in vector insects, but not in human cases. Expanded catalytic models suggest that transmission was interrupted in the study area in 1996 (95% credible interval: 1991-2000), with a resultant decline in the average annual incidence of infection from 0.9% (95% credible interval: 0.6-1.3%) to 0.1% (95% credible interval: 0.005-0.3%). Through a search of archival newspaper reports, we uncovered documentation of a 1995 vector control campaign, and thereby independently validated the model estimates.
  
  
  CONCLUSIONS
  High levels of T. cruzi transmission had been ongoing in peri-rural La Joya prior to interruption of parasite transmission through a little-documented vector control campaign in 1995. Despite the efficacy of the 1995 control campaign, T. cruzi was rapidly reemerging in vector populations in La Joya, emphasizing the need for continuing surveillance and control at the rural-urban interface.
authors.affiliation: School of Geography and Development, University of Arizona, Tucson, Arizona, USA.
authors.forename: Stephen
authors.initials: S
authors.lastname: Delgado
authors.forename: Ricardo
authors.initials: R
authors.lastname: Castillo Neyra
authors.forename: Víctor R
authors.initials: VR
authors.lastname: Quispe Machaca
authors.forename: Jenny
authors.initials: J
authors.lastname: Ancca Juárez
authors.forename: Lily
authors.initials: L
authors.lastname: Chou Chu
authors.forename: Manuela Renee
authors.initials: MR
authors.lastname: Verastegui
authors.forename: Giovanna M
authors.initials: GM
authors.lastname: Moscoso Apaza
authors.forename: César D
authors.initials: CD
authors.lastname: Bocángel
authors.forename: Aaron W
authors.initials: AW
authors.lastname: Tustin
authors.forename: Charles R
authors.initials: CR
authors.lastname: Sterling
authors.forename: Andrew C
authors.initials: AC
authors.lastname: Comrie
authors.forename: César
authors.initials: C
authors.lastname: Náquira
authors.forename: Juan G
authors.initials: JG
authors.lastname: Cornejo del Carpio
authors.forename: Robert H
authors.initials: RH
authors.lastname: Gilman
authors.forename: Caryn
authors.initials: C
authors.lastname: Bern
authors.forename: Michael Z
authors.initials: MZ
authors.lastname: Levy
mesh_terms: D000293:Adolescent; D000328:Adult; D000913:Antibodies, Protozoan / Q000097:blood; D014355:Chagas Disease / Q000188:drug therapy / Q000453:epidemiology* / Q000635:transmission*; D002648:Child; D003140:Communicable Disease Control / Q000266:history* / Q000379:methods*; D003430:Cross-Sectional Studies; D005260:Female; D049673:History, 20th Century; D049674:History, 21st Century; D006801:Humans; D007300:Insect Control / Q000266:history; D008297:Male; D008875:Middle Aged; D010568:Peru / Q000453:epidemiology; D012008:Recurrence; D012424:Rural Population; D016036:Seroepidemiologic Studies; D013997:Time Factors; D019371:Topography, Medical; D014349:Trypanosoma cruzi / Q000276:immunology; D055815:Young Adult
chemical_list: D000913:Antibodies, Protozoan