Molecular detection of Eastern Equine Encephalitis virus in mosquitoes from La Pintada (Antioquia)

ABSTRACT Objective. The detection of emerging and re-emerging arboviruses in mosquitoes from urban and rural areas, is fundamental for predict possible epidemic outbreaks in human populations. The Municipality of La Pintada (Antioquia), is characterized by the presence of dry tropical forest relicts, fishing, tourism, farms and mining. An entomological research was performed for explore the possible circulation of arboviruses of public health importance. Materials and methods. Mosquitoes were captured in urban and rural sites in February-April of 2012. The specimens were stored in liquid nitrogens tanks and were grouped using taxonomic keys for genera. RNA extraction from pools and generic/nested RT-PCR was performed for Flavivirus, Alphavirus, Orthobunyavirus (Group Bunyamwera) and Phlebovirus. Results. 1274 mosquitoes were collected, mainly belonging to Culex and Aedes genera. RNA extracts of 64 pools were tested by RT-PCR and one pool was positive for Alphavirus. Sequencing of the RT- PCR product and the analysis with sequences storage in GenBank designate the presence of Eastern equine encephalitis virus (EEEV). Conclusions. This is the first record of natural infection from EEEV in mosquitoes from La Pintada (Antioquia), an area with ecological elements that favor the emergence of emerging and re-emerging arboviruses of medical and veterinarian importance

Molecular characterization of mosquitoes (Diptera: Culicidae) from the Colombian rainforest

A few studies have carried out the taxonomic and molecular characterization of sylvatic mosquito species in Latin America, where some species have been incriminated as vectors for arboviruses and parasites transmission. The present study reports the molecular characterization of mosquito species in the Sierra Nevada de Santa Marta, a natural ecosystem in the Northern coast of Colombia. Manual capture methods were used to collect mosquitoes, and the specimens were identified via classical taxonomy. The COI marker was used for species confirmation, and phylogenetic analysis was performed using the neighbor-joining method, with the Kimura-2-Parameters model. Aedes serratus , Psorophora ferox , Johnbelkinia ulopus , Sabethes chloropterus , Sabethes cyaneus , Wyeomyia aporonoma , Wyeomyia pseudopecten , Wyeomyia ulocoma and Wyeomyia luteoventralis were identified. We assessed the genetic variability of mosquitoes in this area and phylogenetic reconstructions allowed the identification at the species level. Classical and molecular taxonomy demonstrated to be useful and complementary when morphological characteristics are not well preserved, or the taxonomic group is not represented in public molecular databases

Genomic characterization and seroprevalence studies on alphaviruses in Uruguay

Alphaviruses (Togaviridae) are arboviruses frequently associated with emerging infectious diseases. In this study, we aimed to investigate the presence of alphaviruses in Uruguay by detecting the viral genome in mosquitoes and neutralizing antibodies in equines. A total of 3,575 mosquitoes were analyzed for alphavirus genome detection. Serologic studies were performed on 425 horse sera by plaque reduction neutralization test (PRNT80) against Venezuelan equine encephalitis virus (VEEV) subtype IAB, Pixuna virus (PIXV), Rio Negro virus (RNV), western equine encephalitis virus (WEEV), and Madariaga virus (MADV). Mosquitoes belonging to six genera were captured and 82.9% were identified as Culex pipiens. Two Cx. pipiens pools collected in Fray Bentos and Las Toscas localities were alphavirus positive, and phylogenetic analyses showed that the sequences grouped into two different clusters: the lineage I of eastern equine encephalitis virus and RNV (VEEV complex), respectively. Plaque reduction neutralization test assays showed antibodies against strains of the VEEV complex, MADV, and WEEV. Rio Negro virus was the most geographically widespread virus, showing higher seroprevalences (up to 20%). Seroprevalences against VEEV IAB ranged between 4.6% and 13%; antibodies against PIXV, WEEV, and MADV were less frequent (3–4%). In conclusion, RNV exhibited the highest seroprevalence in horses, a wide geographical distribution, and viral genome was detected in Cx. pipiens mosquitoes. Madariaga virus had a low seroprevalence in equines, but an epizootic lineage typical of North America was detected in Cx. pipiens mosquitoes. Taken together, our results show that alphaviruses are present in Uruguay with variable occurrence and geographical distribution being a potential threat for human and equine health

El virus Madariaga le sigue los pasos a los virus Chikungunya y Zika

Los virus transmitidos por artrópodos son causa de importantes encefalitis. Varios virus de las encefalitis equinas pertenecen a la familia Togaviridae género Alphavirus, además de Chikungunya y Mayaro, están los virus de la encefalitis del oeste (WEEV), encefalitis equina venezolana (VEEV) y encefalitis equina del este (EEEV). La EEEV se clasificó previamente en cuatro linajes / subtipos distintos (I - IV) (1, 2). Las cepas sudamericanas (SA) (linajes II-IV), que incluyen los aislamientos de América del Sur y Central, son genéticamente diferentes en contraste con las cepas de América del Norte (NA) que pertenecen al linaje I (3). Debido a la divergencia genética y a las diferencias significativas en la ecología y la patogénesis, los aislamientos de América del Sur de EEEV se clasificaron recientemente como una especie distinta la que se denominó virus Madariaga (MADV)(1)

Molecular detection of Eastern Equine Encephalitis virus in mosquitoes from La Pintada (Antioquia)

Objective. The detection of emerging and re-emerging arboviruses in mosquitoes from urban and rural areas, is fundamental for predict possible epidemic outbreaks in human populations. The Municipality of La Pintada (Antioquia), is characterized by the presence of dry tropical forest relicts, fishing, tourism, farms and mining. An entomological research was performed for explore the possible circulation of arboviruses of public health importance. Materials and methods. Mosquitoes were captured in urban and rural sites in February-April of 2012. The specimens were stored in liquid nitrogens tanks and were grouped using taxonomic keys for genera. RNA extraction from pools and generic/nested RT-PCR was performed for Flavivirus, Alphavirus, Orthobunyavirus (Group Bunyamwera) and Phlebovirus. Results. 1274 mosquitoes were collected, mainly belonging to Culex and Aedes genera. RNA extracts of 64 pools were tested by RT-PCR and one pool was positive for Alphavirus. Sequencing of the RT-PCR product and the analysis with sequences storage in GenBank designate the presence of Eastern equine encephalitis virus (EEEV). Conclusions. This is the first record of natural infection from EEEV in mosquitoes from La Pintada (Antioquia), an area with ecological elements that favor the emergence of emerging and re-emerging arboviruses of medical and veterinarian importance.Objetivo. La detección de arbovirus emergentes y re-emergentes a partir de mosquitos provenientes de áreas semi-urbanas y rurales es fundamental para predecir posibles eventos epidémicos en poblaciones humanas. En el municipio de La Pintada (Departamento de Antioquia), caracterizado por la presencia de remanentes de bosque seco tropical, actividades de pesca, turismo, explotación agropecuaria y minera, se realizó un estudio entomológico para explorar la posible presencia y circulación de arbovirus de importancia en salud pública. Materiales y Métodos. Los mosquitos adultos fueron recolectados en sitios urbanos y rurales en febrero-abril del año 2012. Los especímenes colectados fueron almacenados en tanques de nitrógeno líquido, y luego separados en grupos utilizando claves taxonómicas para género. Para la detección de los virus se realizó extracción de RNA y RT-PCR genérica/anidada para los géneros Flavivirus, Alphavirus, Orthobunyavirus (Grupo Bunyamwera) y Phlebovirus. Resultados. 1274 mosquitos adultos e inmaduros fueron colectados, pertenecientes en su mayoría a los géneros Culex y Aedes. Los extractos de RNA de 64 pools fueron evaluados por RT-PCR. Se encontró un pool positivo para Alphavirus. La secuenciación de los productos de RT-PCR y el análisis con secuencias depositadas en GenBank indica la presencia del virus de Encefalitis Equina del Este (EEEV). Conclusiones. Este es el primer registro de infección natural del virus de encefalitis equina del este (EEEV) en mosquitos de La Pintada (Antioquia, Colombia), un área con factores ecológicos aptos para la emergencia y re-emergencia de arbovirus de importancia veterinaria y médica