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

Background The 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. Methodology Between 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. Key results We 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. Discussion Knowledge 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. Author summary Dengue, 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. The 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. The 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. Between 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. Public 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.


Introduction
viruses were addressed, in order to improve capacities and informed decision-making about 140 arbovirosis management and prevention. In addition to the active participation in the Asamblea ejidal 141 meetings, a cycle of activities (talks, participatory workshops, community theater) for specific groups 142 (women, children, adolescents) was designed.
143 Study design 144 We conducted a mixed methods study, structured in two complementary phases. Phase I: in June  In 2017, through a structured, standardized and precoded questionnaire (S1.A File), we first obtained 156 information about the sociodemographic characteristics of the household residents. Then we focused in the S1.A File). The interviews were conducted using the head of family as the informant. 164 In 2017 and 2018, through the application of a structured, standardized and pre-coded household 165 observational checklist (S1.A File), we collected information about risk factors for vector 166 proliferation at the domestic level i.e., unprotected water deposits (vases, flowerpots, cans, tires, in S1).

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In 2018, through precoded and semi-structured questions (S1.B File) to household residents and key 176 informants, respectively, we assessed the presence of risk factors for Aedes breeding in the 177 community. The questions focused on the sanitation and hygiene services i.e. the existing facilities 178 for waste collection, the source and frequency of water supply.

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The semi-structured questions were used to triangulate the information recorded in the domiciliary 180 visits, undertaking interviews with six key informants from each community (nursing staff of the 181 local health center, Presidente del Comisariado Ejidal, ejidal committee of health). During the 182 interview, we also collected qualitative data to explore risk perceptions and community's expectations 183 about arboviral diseases and their prevention.

Data management and analysis
The fieldwork of data collection was realized by trained staff and internal students from ECOSUR, services; perceptions about arboviral disease risk factors and its prevention). Data was described and 195 analyzed in order to identify common or recurrent patterns among the explored themes.

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Knowledge, referred and observed practice score system development 197 In order to evaluate each section of the proposed surveys, we created indices (S1.A File) to score the 198 knowledge and practices in question, as was already designed in several previous studies [26][27][28][29][30].

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Questions related to knowledge only allowed a correct answer. Each correct answer was rated 1 point.

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Questions related to practices, allowed several correct answers, so that each interviewee had up to 201 five possible options. Each correct answer was rated with 0.5 points. In any case, the wrong answers,

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or lack of answer, were rated with 0 points. Direct observations, made in the interior and exterior 203 spaces of dwelling unit, focused on two aspects: presence of unprotected water deposits and detection 204 of organic or inorganic solid waste. 1 point was assigned when these elements were absent (observed 205 practices adequate), 0 points if not. A knowledge or practice was considered appropriate when the 206 "overall score" obtained was equal or greater than 60% of the maximum expected score.

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With the data collected, we describe the results with mean and proportions for continuous and

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Sociodemographic characteristics 229 Table 1 shows the study sample sociodemographic characteristics by locality of residence. In the 230 majority of households the average number of inhabitants was of three of more people (82,5%).

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Overall, the most common type of family was "young", represented by a mean age for the household composition members of less than 35 years old (55%). There were no significant differences in 233 education level, sex and age distribution between the localities of the two municipalities. Villahermosa. We also found important problems in the water supply services, completely absent in 240 Tapachula and mostly irregular (80.6%) in Villahermosa, as well as a complete absence of a public drainage system in both sites.

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Both in Villahermosa and in Tapachula, the wells (private or communal) were indicated by all the 243 informants as the main solution to solve the lack of piped water. In Ejido Hidalgo, the lack of a 244 functioning community well, even forced those families without other resources to store rainwater.  reported.    personal support to advance in this work. 363 We also acknowledge the staff of the ECOSUR Health Department of San Cristóbal de Las Casas emergence-of-zika-virus-in-the-americas&Itemid=41711&lang=en