02833nas a2200241   4500000000100000008004100001260002500042653001300067653002400080653001700104100001600121700001700137700002100154700001600175700002000191700001200211700001500223245010900238856007500347490000700422520213700429022002502566       2022                            d  bMary Ann Liebert Inc10aVirology10aInfectious Diseases10aMicrobiology1 aGrijalva MJ1 aVillacís AG1 aOcaña-Mayorga S1 aYumiseva CA1 aNieto-Sanchez C1 aBaus EG1 aMoncayo AL00aEvaluation of the Effectiveness of Chemical Control for Chagas Disease Vectors in Loja Province, Ecuador  uhttps://www.liebertpub.com/doi/pdf/10.1089/vbz.2021.0089?download=true0 v223 a<p>The objective of this study was to evaluate the effectiveness of selective and community-wide house insecticide spraying in controlling triatomines in the subtropical areas of Loja Province, Ecuador. We designed a quasiexperimental pre–post-test without a control group to compare entomological levels before and after spraying. The baseline study was conducted in 2008. Second, third, and fourth visits were conducted in 2010, 2011, and 2012 in three rural communities. Out of the 130 domestic units (DU) visited, 41 domestic units were examined in each of the four visits. Selective and community-wide insecticide interventions included spraying with 5% deltamethrin at 25 mg/m2 active ingredient. At each visit, a questionnaire was administered to identify the characteristics of households, and DUs were searched for triatomine bugs. In addition, parasitological analysis was carried out in life triatomines. One and two rounds of selective insecticide spraying decreased the probability of infestation by 62% (pairwise odds ratios [POR] 0.38, 95% confidence interval [CI] 0.17–0.89, p = 0.024) and 51% (POR 0.49, 95% CI 0.23–1.01, p = 0.054), respectively. A similar effect was observed after one round of community-wide insecticide application in Chaquizhca and Guara (POR 0.55, CI 0.24–1.25, p = 0.155) and Bellamaria (POR 0.62, CI 0.22–1.79, p = 0.379); however, it was not statistically significant. Trypanosoma cruzi infection in triatomines (n = 483) increased overtime, from 2008 (42.9% and 8.5% for Rhodnius ecuadoriensis and Panstrongylus chinai, respectively) to 2012 (79.5% and 100%). Neither of the two spraying methodologies was effective for triatomine control in this area and our results point to a high likelihood of reinfestation after insecticide application. This underscores the importance of the implementation of physical barriers that prevent invasion and colonization of triatomines in households, such as home improvement initiatives, accompanied by a concerted effort to address the underlying socioeconomic issues that keep this population at risk of developing Chagas disease.</p>
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