Positive deviance study to inform a Chagas disease control program in southern Ecuador

Abstract

Chagas disease is caused by Trypanosoma cruzi, which is mainly transmitted by the faeces of triatomine insects that find favourable environments in poorly constructed houses. Previous studies have documented persistent triatomine infestation in houses in the province of Loja in southern Ecuador despite repeated insecticide and educational interventions. We aim to develop a sustainable strategy for the interruption of Chagas disease transmission by promoting living environments that are designed to prevent colonisation of rural houses by triatomines. This study used positive deviance to inform the design of an anti-triatomine prototype house by identifying knowledge, attitudes and practices used by families that have remained triatomine-free (2010-2012). Positive deviants reported practices that included maintenance of structural elements of the house, fumigation of dwellings and animal shelters, sweeping with "insect repellent" plants and relocation of domestic animals away from the house, among others. Participants favoured construction materials that do not drastically differ from those currently used (adobe walls and tile roofs). They also expressed their belief in a clear connection between a clean house and health. The family's economic dynamics affect space use and must be considered in the prototype's design. Overall, the results indicate a positive climate for the introduction of housing improvements as a protective measure against Chagas disease in this region.

Ten years (2004–2014) of Chagas disease surveillance and vector control in Ecuador: successes and challenges

“…ecuadoriensis with insecticide spraying in southern Ecuador has been met with mixed success , possibly due to a rather intrusive behaviour. Similarly, limited house infestation has been observed in the Amazon region, but several opportunistic sylvatic vector species can invade houses to feed on humans, and will require alternative strategies to be implemented for their control . Combining information from entomological and epidemiological surveillance is also key to better identify risk areas.…”

Effectiveness of Large-Scale Chagas Disease Vector Control Program in Nicaragua by Residual Insecticide Spraying Against Triatoma dimidiata

“…28 In addition, encouraging certain behaviors among community members, such as selffumigation of dwellings or relocation of domestic animals away from the house, could offer easy anti-triatomine solutions. 36 At the strategic level, the classical three-phase vector control strategy, that is, preparation, attack, and surveillance, 5 is no longer appropriate in scenarios where T. dimidiata is distributed widely at low levels of infestation. The attack phase of this strategy (i.e., large-scale insecticide spraying) is not cost-effective or affordable for Central American settings.…”

Positive deviance, big data, and development: A systematic literature review

“…A total of 68% of those studies use mixed methods, 21% use quantitative methods, and 11% used qualitative methods. The normal PD approach covered studies that tackled issues including health care–associated infections (de Macedo et al, ; Marra et al, ), enhancing health outcomes of women in disadvantaged circumstances (Long et al, ), cancer prevention (Vossenaar et al, ; Vossenaar, Bermúdez, Anderson, & Solomons, ), child marriage (Lackovich‐Van Gorp, ), child rearing (Aruna, Vazir, & Vidyasagar, ), infectious disease control (Babalola, ; Babalola et al, ; Nieto‐Sanchez, Baus, Guerrero, & Grijalva, ), improving pregnancy outcomes (Ahrari et al, ), counselling for family planning (Kim, Heerey, & Kols, ), child malnutrition (Aday, Hyden, Osking, & Tomedi, ; Bolles, Speraw, Berggren, & Lafontant, ; Guldan et al, ; Kanani & Popat, ; Merchant & Udipi, ; Merita, Sari, & Hesty, ; Roche et al, ; Sethi, Kashyap, Seth, & Agarwal, ; Shekar, Habicht, & Latham, ; Shekar, Habicht, & Latham, ; Wishik & Van Der Vynckt, ), neonatal mortality (Marsh et al, ), and managing medico‐social problems through self‐care (Gidado, Obasanya, Adesigbe, Huji, & Tahir, ).…”