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bioRxiv · 10.1101/581603

Emerging arbovirosis (Dengue, Chikungunya, Zika) in the Southeastern Mexico: influence of social and environmental determinants on knowledge and practices. A mixed method study

Abstract

BackgroundThe incidence and geographical distribution of arboviruses is constantly increasing. The epidemiological patterns of the proliferation of viruses and their vectors (Aedes aegypti and Aedes albopictus) are associated with socio-environmental determinants, and are closely related to human habits, especially at the household level. The aim of this work is to analyze the influence of socio-environmental determinants on the knowledge and practices related to arboviruses and their transmission, among the residents of three communities on the southern border of Mexico.\n\nMethodologyBetween June 2017 and August 2018, our investigation covered a set of 149 households from three communities of Tapachula (Chiapas) and Villahermosa (Tabasco). We first conducted household surveys about knowledge and practices on arbovirosis. Then, we carried out direct observations of risk factors for vector proliferation at the domestic level, before and after exposing a part of the population to a cycle of community engagement prevention activities. Through semi-structured interviews, we also focused on the detection of environmental risk situations for vector breeding at the community level.\n\nKey resultsWe found that most dwellings had an adequate knowledge about the origin and transmission of arboviruses, but only a minority of them also implemented appropriate practices. Higher education levels were associated with better prevention scores. The observations made after the cycle of community activities in Chiapas revealed a decrease in the accumulation of unprotected water deposits. A higher percentage of domestic risk practices were detected in association with significant deficiencies in sanitation and water supply services. Furthermore, the perception of greater risk and difficulty in complying with preventive measures was detected among the population.\n\nDiscussionKnowledge does not necessarily lead to adequate prevention practices. A better understanding of all these dimensions and their interactions is required. In addition to the educational level, intermediate social determinants (such as water supply and environmental sanitation) influence the persistence of behaviors that are risk factors for the proliferation of arbovirosis. The achievement of an effective and sustainable vector management is required to address these related aspects.\n\nAuthor summaryDengue, Chikungunya and Zika are arboviral diseases, transmitted by Aedes mosquitoes. As a result of a continuous increase in the geographical spread and burden of disease, arbovirosis have become a priority issue for global health.\n\nThe proliferation of viruses and their vectors are influenced by a complex interaction of environmental and social determinants. Thus, the design of effective and sustainable prevention and control measures requires an understanding of all these different aspects.\n\nThe aim of our work is to explore the effects of social and environmental factors on the knowledge and practices related to Dengue, Chikungunya and Zika and their transmission, among the residents of three communities on the southern border of Mexico, currently an endemic area. Our study draws on the application of a program combining the implementation of new technologies for vector management with a participatory and holistic multidisciplinary approach.\n\nBetween June 2017 and August 2018, we used different surveys and methodological approaches to explore knowledge and practices on arbovirosis, as well as to identify risk factors for vector proliferation. We found that intermediate social determinants (such as occasional water supply and infrequent waste collections) influence the persistence of behaviors that are risk factors for the proliferation of arbovirosis.\n\nPublic health interventions for arbovirosis prevention must be accompanied by intersectoral work that includes the improvement of these related aspects, according to the multifactorial etiology of arboviruses.

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Causa, R., Luque-Fernandez, M. A., Ochoa, H., Dor, A., Rodriguez, F., Solis, R., Pacheco, A. L.. 2019-03-18. Emerging arbovirosis (Dengue, Chikungunya, Zika) in the Southeastern Mexico: influence of social and environmental determinants on knowledge and practices. A mixed method study. https://doi.org/10.1101/581603

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