Heavy metals in atmospheric deposition in Málaga (SE Spain) and the influence of African dust intrusions

This study reports information on deposition samples collected weekly at a coastal sampling site (Málaga, SE Spain) as part of a research project focused on the impact of atmospheric deposition on the Alborán Sea (W-Mediterranean). This semi-enclosed basin is a transitional area between the Atlantic Ocean and the Mediterranean. Moreover, due to its geographical location the area is frequently affected by intrusions of air masses loaded with high concentrations of atmospheric particulate matter. Major and trace metal analysis of filters and filtrates were aiming at finding the dissolved and non-dissolved fractions of the deposited material. The origin of the air masses reaching the study region was interpreted based on back-trajectories and principal component analysis was performed to find out the groups of elements with similar behaviour. Deposition fluxes at this site were marked by meteorological conditions and the external influence of other sources on a regional scale and the frequency and magnitude of African dust intrusions.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

Antibodies to West Nile virus and related flaviviruses in wild boar, red foxes and other mesomammals from Spain

Red foxes (Vulpes vulpes), wild boar (Sus scrofa) and Iberian pigs (Sus scrofa domestica) that are raised extensively outdoors, as well as other wild mesomammals from south central Spain and wild boar from Doñana National Park (DNP), were tested for antibodies against related flaviviruses by ELISA and for antibodies against WNV by VNT. Mean flavivirus seroprevalence according to ELISA was 20.4 ± 7.8% (21 out of 103) in red foxes, 12.6 ± 2.8% (69 out of 545) in wild boars, and 3.3 ± 2.7% (6 out of 177) in Iberian pigs. A stone marten (Martes foina) also tested positive. Flavivirus seroprevalence in wild boar was significantly higher in DNP, and increased with age. Haemolysis of the serum samples limited interpretation of VNT to 28 samples, confirming WNV seroprevalence in one red fox, four Iberian pigs and nine wild boars. ELISA positive, microVNT negative samples suggest presence of non-neutralizing antibodies against WNV or antibodies to other antigenically related flaviviruses. Despite the importance of wetlands for flavivirus maintenance and amplification, WNV/flavivirus seroprevalence in wild boar and red foxes was not associated to wetland habitats. This is the first report of exposure of red foxes to WNV. With view to use of the tested species as sentinels for flavivirus activity, limited exposure of Iberian pigs that would be available for regular sampling, low numbers of foxes collected and concentration of wild boar harvest in the winter season are major drawbacks.This study has been supported by projects PAC08-0296-7771 (JCCM), and AG2008-02504GAN. A.V. Gutierrez-Guzman is a JCCM fellow (PAC08-029).Peer Reviewe

The Role of Birds of Prey in West Nile Virus Epidemiology

Reported human cases of West Nile virus (WNV) in Europe increased dramatically in 2018. Lineage 1 strains had been circulating in Euro-Mediterranean countries since the early 1990s. The subsequent introduction of WNV lineage 2 has been responsible for the remarkable upsurge of European WNV outbreaks since 2004, including the dramatic increase in human cases observed since 2018. The virus exists in a natural cycle between mosquitoes and wild birds, with humans and horses acting as dead-end hosts. As the key vertebrate hosts in the transmission cycle of WNV, avian species have been the focus of surveillance across many countries. Raptors appear particularly susceptible to WNV infection, resulting in higher prevalence, and in some cases exhibiting neurological signs that lead to the death of the animal. In addition, birds of prey are known to play an important role as WNV reservoir and potentially amplifying hosts of infection. Importantly, raptor higher susceptibility/prevalence may indicate infection through predation of infected prey. Consequently, they are considered important target species when designing cost-effective surveillance for monitoring both seasonal WNV circulation in endemic countries and its emergence into new areas, where migrating raptors may play a critical role in virus introduction. This review summarizes the different aspects of the current knowledge of WNV infection in birds of prey and evaluates their role in the evolution of the epizootic that is spreading throughout Europe

Spatial distribution of radionuclides in marine sediments from Djibouti seamounts (Alboran Sea, Western Mediterranean).

Sediment samples from two seamounts of the Djibouti Banks area – Avempace and Herradura - located at the Motril Marginal Plateau (northern Alboran Sea) were investigated to determine the radioactivity of natural and artificial radionuclides. Changes in the elemental composition of sediment from seamounts may be related to sources and oceanographic conditions in the water column, but also biogeochemical and geochemical processes can be involved during the vertical deposition of particles and in the sediment surface once particles are settled. The particular interest of this area is that the influence of fluvial supplies is scarce and therefore the contribution of aeolian dust inputs to sediments is expected to be high and largely responsible for the sediment’s composition. In this setting, the Sahara and northernmost part of North Africa or Sahel regions are the most likely areas providing dust particles to the Mediterranean Sea. The tops of the Avempace and Herradura seamounts are relatively flat and shallow, with minimum depths of 260–275 m, respectively. In general, both seamounts presented similar average radiological load and the results showed that the spatial distribution of radionuclides was relatively uniform in surface sediments from these two banks. For the anthropogenic 137Cs, the radioactivity ranges from 1.8-6.9 Bq/Kg and can be mainly attributed to the significant supply of aeolian dust from North Africa to the Alboran Sea.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

Ecological factors driving avian influenza virus dynamics in Spanish wetland ecosystems

This is an open-access article distributed under the terms of the Creative Commons Attribution License.-- et al.Studies exploring the ecological interactions between avian influenza viruses (AIV), natural hosts and the environment are scarce. Most work has focused on viral survival and transmission under laboratory conditions and through mathematical modelling. However, more integrated studies performed under field conditions are required to validate these results. In this study, we combined information on bird community, environmental factors and viral epidemiology to assess the contribution of biotic and abiotic factors in the occurrence of low pathogenic AIV in Spanish wetlands. For that purpose, seven locations in five different wetlands were studied during two years (2007-2009), including seven sampling visits by location. In each survey, fresh faeces (n = 4578) of wild birds and water samples were collected for viral detection. Also, the vegetation structure, water physical properties of wetlands, climatic conditions and wild bird community composition were determined. An overall AIV prevalence of 1.7%±0.4 was detected in faecal samples with important fluctuations among seasons and locations. Twenty-six AIV were isolated from the 78 RRT-PCR positive samples and eight different haemagglutinines and five neuraminidases were identified, being the combination H3N8 the most frequent. Variation partitioning procedures identified the combination of space and time variables as the most important pure factor - independently to other factors - explaining the variation in AIV prevalence (36.8%), followed by meteorological factor (21.5%) and wild bird community composition/vegetation structure (21.1%). These results contribute to the understanding of AIV ecological drivers in Spanish ecosystems and provide useful guidelines for AIV risk assessment identifying potential hotspots of AIV activity.This work was financially supported by INIA (Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria), project FAU2006-00019-C03-00 and by Department of Environment, Territorial Planning, Agriculture and Fisheries of the Basque Government. P. Acevedo was supported by a Beatriu de Pinós fellowship funded by Comissionat per a Universitats i Recerca del Departament d'Innovació, Universitats i Empresa, of the Generalitat de Catalunya and the COFUND Programme-Marie Curie Actions under 7th Marc Programme of the European Community.Peer Reviewe

The Detection of SARS-CoV-2 Antibodies in an Exposed Human Population Is Biased by the Immunoassay Used: Implications in Serosurveillance

The presence of SARS-CoV-2 antibodies was examined over 7 months in a population of essential service workers exposed during the first epidemic wave in Madrid (Spain). Results obtained with different serological assays were compared. Firstly, serum samples obtained in April 2020 were analyzed using eleven SARS-CoV-2 antibody detection methods, including seven ELISAs, two CLIAs and two LFAs. While all of the ELISA tests and the Roche eCLIA method showed good performance, it was poorer for the Abbott CLIA and LFA tests. Sera from 115 workers with serologically positive results in April were collected 2 and 7 months after the first sampling and were analyzed using five of the tests previously assessed. The results showed that while some ELISA tests consistently detected the presence of anti-SARS-CoV-2 antibodies even 7 months after first detection, other methods, such as the Abbott CLIA test, showed an important reduction in sensitivity for these mature antibodies. The sensitivity increased after establishing new cut-off values, calculated taking into account both recent and old infections, suggesting that an adjustment of assay parameters may improve the detection of individuals exposed to the infection.This research was funded by the Madrid City Council (Specific epidemiological and health studies of COVID-19 to know the prevalence of the disease in essential operational sectors).S

Pathogenicity of two recent Western Mediterranean West Nile virus isolates in a wild bird species indigenous to Southern Europe: the red-legged partridge

West Nile virus (WNV) is an emerging zoonotic pathogen whose geographic spread and incidence in humans, horses and birds has increased significantly in recent years. WNV has long been considered a mild pathogen causing self-limiting outbreaks. This notion has changed as WNV is causing large epidemics with a high impact on human and animal health. This has been particularly noteworthy since its introduction into North America in 1999. There, native bird species have been shown to be highly susceptible to WNV infection and disease with high mortalities. For this reason, the effect of WNV infection in North American bird species has been thoroughly studied by means of experimental inoculations in controlled trials. To a lesser extent, European wild birds have been shown to be affected clinically by WNV infection. Yet experimental studies on European wild bird species are lacking. The red-legged partridge (Alectoris rufa) is a gallinaceous bird indigenous to the Iberian Peninsula, widely distributed in South Western Europe. It plays a key role in the Mediterranean ecosystem and constitutes an economically important game species. As such it is raised intensively in outdoor facilities. In this work, red-legged partridges were experimentally infected with two recent WNV isolates from the Western Mediterranean area: Morocco/2003 and Spain/2007. All inoculated birds became viremic and showed clinical disease, with mortality rates of 70% and 30%, respectively. These results show that Western Mediterranean WNV variants can be pathogenic for some European bird species, such as the red-legged partridge

Pathogenesis and transmissibility of highly (H7N1) and low (H7N9) pathogenic avian influenza virus infection in red-legged partridge (Alectoris rufa)

An experimental infection with highly pathogenic avian influenza virus (HPAIV) and low pathogenic avian influenza virus (LPAIV) was carried out in red-legged partridges (Alectoris rufa) in order to study clinical signs, gross and microscopic lesions, and viral distribution in tissues and viral shedding. Birds were infected with a HPAIV subtype H7N1 (A/Chicken/Italy/5093/1999) and a LPAIV subtype H7N9 (A/Anas crecca/Spain/1460/2008). Uninoculated birds were included as contacts in both groups. In HPAIV infected birds, the first clinical signs were observed at 3 dpi, and mortality started at 4 dpi, reaching 100% at 8 dpi. The presence of viral antigen in tissues and viral shedding were confirmed by immunohistochemistry and quantitative real time RT-PCR (qRRT-PCR), respectively, in all birds infected with HPAIV. However, neither clinical signs nor histopathological findings were observed in LPAIV infected partridges. In addition, only short-term viral shedding together with seroconversion was detected in some LPAIV inoculated animals. The present study demonstrates that the red-legged partridge is highly susceptible to the H7N1 HPAIV strain, causing severe disease, mortality and abundant viral shedding and thus contributing to the spread of a potential local outbreak of this virus. In contrast, our results concerning H7N9 LPAIV suggest that the red-legged partridge is not a reservoir species for this virus

Ecological Factors Driving Avian Influenza Virus Dynamics in Spanish Wetland Ecosystems

Studies exploring the ecological interactions between avian influenza viruses (AIV), natural hosts and the environment are scarce. Most work has focused on viral survival and transmission under laboratory conditions and through mathematical modelling. However, more integrated studies performed under field conditions are required to validate these results. In this study, we combined information on bird community, environmental factors and viral epidemiology to assess the contribution of biotic and abiotic factors in the occurrence of low pathogenic AIV in Spanish wetlands. For that purpose, seven locations in five different wetlands were studied during two years (2007-2009), including seven sampling visits by location. In each survey, fresh faeces (n = 4578) of wild birds and water samples were collected for viral detection. Also, the vegetation structure, water physical properties of wetlands, climatic conditions and wild bird community composition were determined. An overall AIV prevalence of 1.7%±0.4 was detected in faecal samples with important fluctuations among seasons and locations. Twenty-six AIV were isolated from the 78 RRT-PCR positive samples and eight different haemagglutinines and five neuraminidases were identified, being the combination H3N8 the most frequent. Variation partitioning procedures identified the combination of space and time variables as the most important pure factor - independently to other factors - explaining the variation in AIV prevalence (36.8%), followed by meteorological factor (21.5%) and wild bird community composition/vegetation structure (21.1%). These results contribute to the understanding of AIV ecological drivers in Spanish ecosystems and provide useful guidelines for AIV risk assessment identifying potential hotspots of AIV activity

Empleo del Vitrofural en la esterilización química del endospermo artificial de los embriones somáticos encapsulados de Saccharum spp. híbrido var Cuba 87- 51

The effect of the Vitrofural in the control of pollutants in the capsule study was carried out, as well as its toxic effect on the somatic embryos of sugar cane. Different dose of this compound was used (20, 25, 30, 35 and 40 mg l-1), these they were applied to the cultivation medium with nudes somatic embryos, which was used previously autoclaved and without autoclaved, later these same doses were added to the synthetic endosperm. The Vitrofural can be employed in the chemical sterilization of the cultivation medium for the germination in vitro of the somatic embryos, as well as in the chemical protection of the synthetic endosperm, that which allowed to eliminate the autoclaved of the encapsulation medium, as well as to reduce the concentration of the agents gelificantes in 33% and to carry out all the operations under non sterile conditions.Key words: Encapsulation, sugarcane, synthetic seedLa contaminación microbiana del endospermo sintético es uno de los principales problemas que enfrenta la tecnología de la semilla artificial. En el presente trabajo se realizó un estudio sobre el efecto del Vitrofural en el control de contaminantes en la cápsula, así como el efecto tóxico de este producto sobre los embriones somáticos de caña de azúcar. Se emplearon concentraciones de 20, 25, 30, 35 y 40 mg.l-1, estas fueron aplicadas al medio de cultivo con embriones somáticos desnudos. Este medio de cultivo fue empleado autoclaveado y sin autoclavear, posteriormente se añadieron estas mismas concentraciones al endospermo sintético de los embriones encapsulados de caña de azúcar. Se comprobó que el Vitrofural puede ser empleado en la esterilización química de los medios de cultivo para la germinación in vitro de los embriones somáticos, así como en la protección química del endospermo sintético, lo cual permitió eliminar el autoclaveo del medio de cultivo de encapsulación, así como reducir la concentración de los agentes gelificantes en un 33% y realizar todas las operaciones en condiciones no estériles.Palabras clave: Encapsulación, caña de azúcar, semilla sintétic