title: Implementing a vector surveillance-response system for chagas disease control: a 4-year field trial in Nicaragua.
abstract: BACKGROUND
  Chagas disease is one of the neglected tropical diseases (NTDs). International goals for its control involve elimination of vector-borne transmission. Central American countries face challenges in establishing sustainable vector control programmes, since the main vector, Triatoma dimidiata, cannot be eliminated. In 2012, the Ministry of Health in Nicaragua started a field test of a vector surveillance-response system to control domestic vector infestation. This paper reports the main findings from this pilot study.
  
  
  METHODS
  This study was carried out from 2012 to 2015 in the Municipality of Totogalpa. The Japan International Cooperation Agency provided technical cooperation in designing and monitoring the surveillance-response system until 2014. This system involved 1) vector reports by householders to health facilities, 2) data analysis and planning of responses at the municipal health centre and 3) house visits or insecticide spraying by health personnel as a response. We registered all vector reports and responses in a digital database. The collected data were used to describe and analyse the system performance in terms of amount of vector reports as well as rates and timeliness of responses.
  
  
  RESULTS
  During the study period, T. dimidiata was reported 396 times. Spatiotemporal analysis identified some high-risk clusters. All houses reported to be infested were visited by health personnel in 2013 and this response rate dropped to 39% in 2015. Rates of insecticide spraying rose above 80% in 2013 but no spraying was carried out in the following 2 years. The timeliness of house visits improved significantly after the responsibility was transferred from a vector control technician to primary health care staff.
  
  
  CONCLUSIONS
  We argue that the proposed vector surveillance-response system is workable within the resource-constrained health system in Nicaragua. Integration to the primary health care services was a key to improve the system performance. Continual efforts are necessary to keep adapting the surveillance-response system to the dynamic health systems. We also discuss that the goal of eliminating vector-borne transmission remains unachievable. This paper provides lessons not only for Chagas disease control in Central America, but also for control efforts for other NTDs that need a sustainable surveillance-response system to support elimination.
authors.affiliation: Doctor of Public Health Program, Harvard T.H. Chan School of Public Health, Boston, USA. yoshiokakota@gmail.com.|School of Tropical Medicine and Global Health, Nagasaki University, Nagasaki, Japan. yoshiokakota@gmail.com.|Former Chagas Disease Control Project, Japan International Cooperation Agency, Managua, Nicaragua. yoshiokakota@gmail.com.
authors.forename: Kota
authors.identifier: http://orcid.org/0000-0001-8463-4913
authors.initials: K
authors.lastname: Yoshioka
authors.affiliation: Former Chagas Disease Control Project, Japan International Cooperation Agency, Managua, Nicaragua.
authors.forename: Doribel
authors.initials: D
authors.lastname: Tercero
authors.affiliation: Former Chagas Disease Control Project, Japan International Cooperation Agency, Managua, Nicaragua.
authors.forename: Byron
authors.initials: B
authors.lastname: Pérez
authors.affiliation: Former Chagas Disease Control Project, Japan International Cooperation Agency, Managua, Nicaragua.
authors.forename: Jiro
authors.initials: J
authors.lastname: Nakamura
authors.affiliation: Former Chagas Disease Control Project, Japan International Cooperation Agency, Managua, Nicaragua.|Department of Disease Prevention, Ministry of Health in Nicaragua, Managua, Nicaragua.
authors.forename: Lenin
authors.initials: L
authors.lastname: Pérez
mesh_terms: D000818:Animals; D014355:Chagas Disease / Q000453:epidemiology / Q000517:prevention & control*; D006801:Humans; D007300:Insect Control / Q000379:methods*; D007303:Insect Vectors / Q000187:drug effects / Q000469:parasitology; D058069:Neglected Diseases / Q000453:epidemiology / Q000517:prevention & control; D009527:Nicaragua / Q000453:epidemiology; D010865:Pilot Projects; D011159:Population Surveillance / Q000379:methods*; D015397:Program Evaluation; D014224:Triatoma / Q000187:drug effects / Q000469:parasitology
keywords: Chagas disease; Nicaragua; Programme integration; Surveillance-response system; Triatoma dimidiata; Vector control