The Doñana Biological Station studies the circulation of the West Nile Virus in the Guadalquivir

The Spanish National Research Council (CSIC) launches a research project to monitor mosquito populations and the presence of virus West Nile in real time in several locations in the lower Guadalquivir during 2021 and 2022. It is planned to carry out weekly captures of the díptera in the Sevillian municipalities of Coria del Río, Puebla del Río and Palomares del Río, the three localities of the area being most affected by the West Nile Virus last year. Researchers will carry out a monitoring work through molecular analysis to detect the presence of the virus in insects. The project is promoted by the CSIC Global Health PTI and is funded by the European Union recovery plan for the Covid-19 crisis.  

The outbreak of the West Nile Virus in the provinces of Seville, Cádiz and Badajoz caused 77 cases of serious illness and 7 deaths. Although most human infections are asymptomatic, the disease can lead to meningitis, encephalitis and acute flaccid paralysis. Experts highlight the importance of entomological surveillance programs to prevent new outbreaks. For decades, the CSIC has collaborated with institutions such as the Mosquito Control Service of the Huelva Provincial Council, the Animal Health Research Centre (CISA-INIA-CSIC), the Center for Biomedical Research in the Epidemiology and Public Health Network (CIBER ISCIII) and the Carlos III Health Institute. 

"With this project we hope that the search for viruses in mosquitoes will allow us to detect the moments of greatest risk of virus transmission in the area in advance", explains Jordi Figuerola, CSIC researcher at the Doñana Biological Station (EBD-CSIC). "We are confident –he adds- in being able to identify the diversity of viruses transmitted by mosquitoes in the area and to understand the mechanisms by which they remain in circulation. It is necessary to better understand how climatic and ecological conditions affect the transmission of the West Nile virus to predict the risk of transmission each season based on environmental conditions and to understand how climate change can affect the transmission of these viruses ".

The scientist hope that results will have an impact in both the short and medium term. "In the first place, during the duration of the project, it will allow us to warn the health authorities if there is a high incidence of the West Nile virus in the area. In the medium term, we hope to be able to predict changes in mosquito populations and the risk of virus transmission weeks in advance"says Figuerola.

Experiencia en la detección

The research team participating in the project has been working with mosquito populations in the area for years to determine how they affect the climate and the environment in their distribution and abundance, as well as the diseases they can transmit. In 2020, as a consequence of the outbreak detected in Andalusia and Extremadura, they focused on determining whether the virus was transmitted in urban areas and finding out what species of mosquitoes and birds were involved.

The data confirmed that the virus had been transmitted within the towns of Coria del Río, Puebla del Río and Palomares del Río and that the main transmitters were two indigenous species of mosquitoes: Culex perexiguus and Culex pipiens. The study, developed with funds from the CSIC, also pointed out that the virus multiplied in birds such as blackbirds and sparrows, which live in urban areas, and was transmitted to people through mosquitoes in urban areas. 

The EBD-CSIC offers updated information every week on the abundance of mosquitoes in the Lower Guadalquivir through the website http://mosquitos.ebd.csic.es . 


www.csic.es/es/actualidad-del-csic/cientificos-del-csic-investigan-la-circulacion-del-virus-del-nilo-en-el

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The use of roads in protected areas and its effects on avian scavenger guild

The use of roads in protected areas and its effects on avian scavenger guild

The expansion of road networks and the increase in traffic have emerged in recent years as key threats to the conservation of biodiversity. This is particularly concerning in many protected areas because the increase of recreational activities requiring the use of vehicles. Effects of roads and traffic within guild scenarios and ecological processes remain however poorly known. This study examined how road proximity and traffic intensity influence patterns of resource use in an Old-World avian scavenger guild living in a protected natural park in northern Spain. 130 carcasses were experimentally placed at different distances from a scenic road in the centre of the park. Vehicles were recorded by means of traffic counters which revealed that maximum numbers were reached during weekends and holidays and during the middle hours of the day. Avian scavenger attendance at carcasses was recorded by means of camera-traps. Obligated scavengers, Eurasian griffon and Egyptian vultures were frequently observed (59.4% and 37.7% of the consumed carcasses) together with five other facultative scavenger species. It was found that the richness (number of species) and the probability of consumption of the resource were reduced the smaller the distance to the road and in days with higher traffic intensity. The same factors affected the probability of presence of all the scavenger species. Moreover, some of them, notably griffon vultures, showed hourly patterns of carcass attendance suggesting avoidance of maximum traffic levels. These results highlight that roads and traffic would trigger consequences on the structure and functioning of scavenger food webs, which may be particularly concerning in protected areas with remarkable levels of biodiversity. Future regulations at protected areas should couple both traffic and tourist affluence with wildlife conservation. In this way important ecological processes would be preserved while maintaining a good dissemination of natural values. informacion[at]ebd.csic.es Donazar et al (2018) Tourism in protected areas: Disentangling road and traffic effects on intra-guild scavenging processes. Sci Total Environ https://doi.org/10.1016/j.scitotenv.2018.02.186


https://www.sciencedirect.com/science/article/pii/S0048969718305850?via%3Dihub