At the tip of an iceberg: citizen science and active surveillance collaborating to broaden the known distribution of Aedes japonicus in Spain

BACKGROUND

Active surveillance aimed at the early detection of invasive mosquito species is usually focused on seaports and airports as points of entry, and along road networks as dispersion paths. In a number of cases, however, the first detections of colonizing populations are made by citizens, either because the species has already moved beyond the implemented active surveillance sites or because there is no surveillance in place. This was the case of the first detection in 2018 of the Asian bush mosquito, Aedes japonicus, in Asturias (northern Spain) by the citizen science platform Mosquito Alert.

METHODS

The collaboration between Mosquito Alert, the Ministry of Health, local authorities and academic researchers resulted in a multi-source surveillance combining active field sampling with broader temporal and spatial citizen-sourced data, resulting in a more flexible and efficient surveillance strategy.

RESULTS

Between 2018 and 2020, the joint efforts of administrative bodies, academic teams and citizen-sourced data led to the discovery of this species in northern regions of Spain such as Cantabria and the Basque Country. This raised the estimated area of occurrence of Ae. japonicus from < 900 km2 in 2018 to > 7000 km2 in 2020.

CONCLUSIONS

This population cluster is geographically isolated from any other population in Europe, which raises questions about its origin, path of introduction and dispersal means, while also highlighting the need to enhance surveillance systems by closely combining crowd-sourced surveillance with public health and mosquito control agencies' efforts, from local to continental scales. This multi-actor approach for surveillance (either passive and active) shows high potential efficiency in the surveillance of other invasive mosquito species, and specifically the major vector Aedes aegypti which is already present in some parts of Europe.

Linking soil variability with plant community composition along a mine-slope topographic gradient: Implications for restoration

Soil heterogeneity generated during the topographic restoration of opencast coalmines determines important differences in vegetation dynamics. The relationship between soil and vegetation along a reclaimed mine slope was assessed. Two vegetation patches (grassland and shrubland) were distinguished and compared with the adjacent forest. Seven sampling transects (3:3:1, grassland:shrubland:forest) were implemented for soil and vegetation characterization. Eleven years after reclamation significant differences between the reference community and the reclaimed communities, and along the reclaimed mine slope, were found. A topographic gradient was observed in the vegetation distribution associated with water and organic matter content: Grassland patches occupy the upper parts of the mine slope to where easily oxidizable-carbon/total-carbon ratio increases and shrubland patches occupy the lower parts towards where water retention capacity increases. The plant species segregation along the mine-slope topographic gradient was related to stages of different maturity of vegetation and soil properties. Novel aspects in plant-soil systems understanding in reclaimed mine slopes were addressed.

Surveillance of Mosquitoes (Diptera, Culicidae) in a Northern Central Region of Spain: Implications for the Medical Community

Mosquitoes are important to public and animal health due to their capacity to transmit diseases. Since the Zika virus was declared a pandemic by the WHO in 2016, and it has been recorded in different regions of Mediterranean Area (included Spain), the Government of La Rioja (Northern Spain) through the Center of Rickettsiosis and Arthropod-Borne Diseases, implemented an entomological surveillance programme of mosquitoes in La Rioja and in a close area of Navarra. This surveillance extended to some of the pathogens that they can transmit. Here we describe the framework of the initial surveillance programme for the detection of mosquitoes and associated human pathogens. We outline the benefits and the limitation of the programme to date, and explore how greater benefits can be achieved, for example using a One Health approach. Entomological surveillance has been carried out with BG-Sentinel traps, human bait technique and other methods such as collecting adults in resting places or immature stages by dipping in several wetlands. Since Aedes albopictus, vector of arbovirus such as Dengue, Chikungunya, and Zika, has not been detected yet in the region, the entomological programme included the surveillance of this exotic species using ovitraps in the most important cities. Morphological identification was supported using the mitochondrial cytochrome C oxidase subunit I and the internal transcribed spacer 2 genes analysis. In 2016 and 2017, more than 6,000 mosquitoes were collected. The mosquito's community included 21 species associated with six genera: Anopheles (n = 4), Aedes (n = 5), Culex (n = 6), Culiseta (n = 4), Uranotaenia (n = 1) and Coquillettidia (n = 1). Eleven species represent new records for La Rioja and Navarra regions. Several species were collected biting humans and a great proportion of the sampled mosquito population are competent vectors of several pathogens, such as West Nile virus. Sequences closely related to mosquito–only flavivirus have been detected in 0.34% of analysed pools. At the same time, the epidemiological surveillance emphasis is placed in the early detection of mosquito-borne diseases in primary health and emergency services. The surveillance programme represents a relevant and necessary assessment of the risk of pathogen transmission in a region, and it allows for the establishment of the appropriate preventive measures.

Drip water electrical conductivity as an indicator of cave ventilation at the event scale

The use of speleothems to reconstruct past climatic and environmental change through chemical proxies is becoming increasingly common. Speleothem chemistry is controlled by hydrological and atmospheric processes which vary over seasonal time scales. However, as many reconstructions using speleothem carbonate are now endeavouring to acquire information about precipitation and temperature dynamics at a scale that can capture short term hydrological events, our understanding of within cave processes must match this resolution. Monitoring within Cueva de Asiul (N. Spain) has identified rapid (hourly resolution) changes in drip water electrical conductivity (EC), which is regulated by the pCO2 in the cave air. Drip water EC is therefore controlled by different modes of cave ventilation. In Cueva de Asiul a combination of density differences, and external pressure changes control ventilation patterns. Density driven changes in cave ventilation occur on a diurnal scale at this site irrespective of season, driven by fluctuations in external temperature across the cave internal temperature threshold. As external temperatures drop below those within the cave low pCO2 external air enters the void, facilitating the deposition of speleothem carbonate and causing a reduction in measured drip water EC. Additionally, decreases in external pressure related to storm activity act as a secondary ventilation mechanism. Reductions in external air pressure cause a drop in cave air pressure, enhancing karst air draw down, increasing the pCO2 of the cave and therefore the EC measured within drip waters. EC thereby serves as a first order indicator of cave ventilation, regardless of changes in speleothem drip rates and karst hydrological conditions. High resolution monitoring of cave drip water electrical conductivity reveals the highly sensitive nature of ventilation dynamics within cave environments, and highlights the importance of this for understanding trace element incorporation into speleothem carbonate at the event scale.

Multiple ecosystem services landscape index: a tool for multifunctional landscapes conservation

The contribution of ecosystems to human well-being has been widely recognised. Taking into account existing trade-offs between ecosystem services (ES) at the farm scale and the dependence of multiple ES on processes that take place at the landscape scale, long-term preservation of multifunctional landscapes must be a priority. Studies carried out from such perspective, and those that develop appropriate indicators, could provide useful tools for integrating ES in landscape planning. In this study we propose a new integrative environmental indicator based on the ES provided by the landscape and named "multiple ecosystem services landscape index" (MESLI). Because synergies and trade-offs between ES are produced at regional or local levels, being different from those perceived at larger scales, MESLI was developed at municipality level. Furthermore, in order to identify main drivers of change in ES provision at the landscape scale an analysis of the relationship between the environmental and the socioeconomic characteristics of the municipalities was carried out. The study was located in the Basque Country and the results demonstrated that the MESLI index is a good tool to measure landscape multifunctionality at local scales. It is effective evaluating landscapes, distinguishing between municipalities based on ES provision, and identifying the drivers of change and their effects. This information about ES provisioning at the local level is usually lacking; therefore, MESLI would be very useful for policy-makers and land managers because it provides relevant information to local scale decision-making.

infantum periendemic northern Spain

Leishmania spp. infection was investigated in tissue samples of wild carnivores from the Spanish Basque Country (BC), by PCR and DNA sequencing. The region is at the northern periphery of Leishmania infantum endemic Iberian Peninsula and infection in the dog (reservoir) or other species has not been previously reported. Leishmania kinetoplast DNA was detected by real-time PCR (rtPCR) in 28% (44/156) of animals. Specifically, in 26% of Eurasian badgers (n=53), 29% of foxes (n=48), 29% of stone martens (n=21) and in 25-50% of less numerous species including genets, wild cats, pole cats, European mink and weasels. Infected animals particularly badgers, were most prevalent in the southernmost province of the BC (Araba) in areas dominated by arable land. Subsequent amplification and sequencing of a fragment of the rRNA internal transcribed spacer 2 (ITS2) from a subset of rtPCR positives samples confirmed the species as L. infantum, showing a high sequence homogeneity with ITS2 sequences of L. infantum from dogs and humans from southern Spain. In summary, this study reports for the first time L. infantum infection in wild carnivores from the BC including in stone martens, pole cats and minks in which infection has not been previously described. It supports the need to study infection in dogs and people in this region and is an example of the value of infection surveillance in wildlife to assess potential risks in the domestic environment and their role in spreading infections in non-endemic areas.