Infect. dis. poverty; 6 (18), 2017
Publication year: 2017
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 resourceconstrained 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.