ABSTRACT This study was designed to assess whether churches in endemic dengue districts in Merida, Mexico provide suitable breeding habitats for mosquitoes and are potential sites for dengue virus (DENV) transmission. Churches were inspected for immature and adult mosquitoes once every week from November 2015 to October 2016. A total of 10,997 immatures of five species were collected. The most abundant species were Aedes aegypti (6,051) and Culex quinquefasciatus (3,018). The most common source of immature Ae. aegypti were buckets followed by disposable containers. Adult collections yielded 21,226 mosquitoes of nine species. The most common species were Cx. quinquefasciatus (15,215) and Ae. aegypti (3,902). Aedes aegypti were found all year long. Female Ae. aegypti (1,380) were sorted into pools (166) and assayed for flavivirus RNA by RT-PCR and Sanger sequencing. Two pools were positive for DENV (DENV-1 and 2). In conclusion, we demonstrated that some churches in Merida are infested with mosquitoes all year long and they potentially serve as sites for DENV transmission and should therefore be considered for inclusion in mosquito and arboviruses control and surveillance efforts.

ABSTRACT Aedes aegypti is the vector of the arboviruses causing dengue, chikungunya and zika infections in Mexico. However, its presence in public places has not been fully evaluated. In a cemetery from Merida, Yucatan, Mexico, the productivity of Ae. aegypti, the gonotrophic cycle, and the presence of Ae. aegypti females infected with arboviruses were evaluated. Immature and adult mosquitoes were inspected every two months between April 2016 to June 2017. For the gonotrophic cycle length, the daily pattern of total and parous female ratio was registered and was analyzed using time series analysis. Ae. aegypti females were sorted into pools and assayed for flavivirus RNA by RT-PCR and Sanger sequencing. Aedes aegypti immatures represented 82.86% (8,627/10,411) of the collection. In total, 1,648 Ae. aegypti females were sorted into 166 pools. Two pools were positive; one for dengue virus (DENV-1) and the other for zika virus (ZIKV). The phylogenetic analysis revealed that the DENV-1 is more closely related to isolates from Brazil. While ZIKV is more closely related to the Asian lineage, which were isolates from Guatemala and Mexico. We report some evidence of vertical transmission of DENV-1 in nulliparous females of Ae. aegypti. The gonotrophic cycle was four and three days in the rainy and dry season, respectively. The cemetery of Merida is an important focus of Ae. aegypti proliferation, and these environments may play a role in arboviruses transmission; probably limiting the efficacy of attempts to suppress the presence of mosquitoes in domestic environments.

OBJECTIVE: Novel, inexpensive solutions are needed for improved management of vector-borne and other diseases in resource-poor environments. Emerging free software providing access to satellite imagery and simple editing tools (e.g. Google EarthTM) complement existing geographic information system (GIS) software and provide new opportunities for: (i) strengthening overall public health capacity through development of information for city infrastructures; and (ii) display of public health data directly on an image of the physical environment. METHODS: We used freely accessible satellite imagery and a set of feature-making tools included in the software (allowing for production of polygons, lines and points) to generate information for city infrastructure and to display disease data in a dengue decision support system (DDSS) framework. FINDINGS: Two cities in Mexico (Chetumal and Merida) were used to demonstrate that a basic representation of city infrastructure useful as a spatial backbone in a DDSS can be rapidly developed at minimal cost. Data layers generated included labelled polygons representing city blocks, lines representing streets, and points showing the locations of schools and health clinics. City blocks were colour-coded to show presence of dengue cases. The data layers were successfully imported in a format known as shapefile into a GIS software. CONCLUSION: The combination of Google EarthTM and free GIS software (e.g. HealthMapper, developed by WHO, and SIGEpi, developed by PAHO) has tremendous potential to strengthen overall public health capacity and facilitate decision support system approaches to prevention and control of vector-borne diseases in resource-poor environments.

OBJETIVO: Se necesitan soluciones novedosas y de bajo costo para mejorar la gestión de las enfermedades de transmisión vectorial y de otro tipo en los entornos con recursos escasos. Las nuevas opciones de software gratuito que dan acceso a imágenes por satélite y a instrumentos de edición sencillos (por ejemplo Google EarthTM) complementan el software del sistema de información geográfica (SIG) existente y brindan nuevas oportunidades para: (i) reforzar la capacidad global de salud pública mediante la elaboración de información para infraestructuras urbanas; y (ii) mostrar los datos de salud pública directamente en una imagen del entorno físico. MÉTODOS: Se utilizaron imágenes por satélite de libre acceso y una serie de prestaciones de generación de detalles incluidas en el software (que permiten crear polígonos, líneas y puntos) para añadir información sobre las infraestructuras urbanas y representar datos sobre las enfermedades en el marco de un sistema de apoyo decisional para el dengue (DDSS). RESULTADOS: Se utilizaron dos ciudades de México (Chetumal y Mérida) para demostrar que es posible desarrollar rápidamente y con un costo mínimo una representación básica de la infraestructura urbana que revista utilidad como urdimbre espacial en un DDSS. Las capas de información generadas comprendían polígonos etiquetados que representaban cuadras, líneas que reproducían las calles, y puntos que indicaban la localización de las escuelas y los dispensarios. Las cuadras se codificaron mediante colores en función de los casos de dengue. Las capas de información se pudieron importar satisfactoriamente a un software SIG en el formato conocido como shapefiles. CONCLUSIÓN: La combinación de Google EarthTM y software SIG gratuito (por ejemplo, HealthMapper, desarrollado por la OMS, y SIGEpi, desarrollado por la OPS) brinda enormes posibilidades para reforzar la capacidad general de salud pública y facilitar la aplicación de sistemas de apoyo decisional a la prevención y el control de enfermedades de transmisión vectorial en los entornos con recursos escasos.

OBJECTIF: Des solutions innovantes et peu onéreuses sont nécessaires pour améliorer la prise en charge des maladies à transmission vectorielle et autres dans les environnements pauvres en ressources. Les logiciels émergents gratuits qui fournissent un accès à l'imagerie satellitaire et à des outils d'édition simples (Google EarthTM) complètent les logiciels de système d'information géographique (GIS) et offrent de nouvelles possibilités : (i) de renforcer les capacités globales de la santé publique par la génération d'informations concernant les infrastructures urbaines ; et (ii) d'afficher directement des données de santé publique sur une image de l'environnement physique. MÉTHODES: Nous avons utilisé l'imagerie satellitaire en accès libre et une série d'outils de traçage appartenant au logiciel (permettant de produire des polygones, des lignes et des points) pour générer des informations sur l'infrastructure urbaine et pour afficher des données de morbidité dans le cadre d'un système d'aide à la décision concernant la dengue (DDSS). RÉSULTATS: Nous nous sommes servis de deux villes du Mexique (Chetumal et Merida) pour démontrer qu'il était possible de développer rapidement et à un coût minimal une représentation rudimentaire des infrastructures urbaines, utilisable comme épine dorsale spatiale d'un DDSS. Les couches de données générées comprenaient des polygones étiquetés représentant des pâtés de maisons, des lignes figurant des rues et des points indiquant l'emplacement d'écoles et de centres de santé. Les pâtés de maisons ont été colorés selon un code de manière à signaler la présence de cas de dengue. Ces couches de données ont été importées avec succès sous un format appelé fichier de formes dans un logiciel GIS. CONCLUSION: La combinaison associant Google EarthTM et un logiciel GIS libre et gratuit (par exemple HealthMapper, développé par l'OMS, ou SIGEpi, développé par l'OPS) offre un énorme potentiel pour renforcer les capacités générales de la santé publique et faciliter l'utilisation de systèmes d'aide à la décision pour prévenir et combattre les maladies à transmission vectorielle dans les environnements pauvres en ressources.