Publications by authors named "Francisco Llorente"

Background: West Nile virus (WNV) is the most widely distributed mosquito-borne flavivirus. Over the past decade, its spread across Europe has raised significant concerns for both public and animal health. Although WNV exposure has been evidenced in various wild mammal species in Spain, no seroepidemiological studies have been conducted on this flavivirus in wild lagomorphs so far.

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West Nile virus (WNV) is a re-emerging flavivirus, primarily circulating among avian hosts and mosquito vectors, causing periodic outbreaks in humans and horses, often leading to neuroinvasive disease and mortality. Spain has reported several outbreaks, most notably in 2020 with seventy-seven human cases and eight fatalities. WNV has been serologically detected in horses in the Community of Madrid, but to our knowledge, it has never been reported from wild birds in this region.

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West Nile virus (WNV) is the most widely distributed mosquito-borne flavivirus in the world. This flavivirus can infect humans causing in some cases a fatal neurological disease and birds are the main reservoir hosts. WNV is endemic in Spain, and human cases have been reported since 2004.

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Background: Vector-borne diseases like West Nile virus (WNV) pose a global health challenge, with rising incidence and distribution. mosquitoes are crucial WNV vectors. Avian species composition and bird community diversity, along with vector communities, influence WNV transmission patterns.

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A barn owl (Tyto alba) died with neurological signs compatible with a viral infection. After discarding other possible infections caused by circulating viruses in the area, analysis of the central nervous system using a pan-viral microarray revealed hybridization to canary bornavirus 2 (CnBV-2). Subsequent sequence analysis confirmed the presence of a virus sharing more than 83% identity with CnBV-2.

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West Nile virus (WNV) is a re-emerging zoonotic pathogen with increasing incidence in Europe, producing a recent outbreak in 2020 in Spain with 77 human cases and eight fatalities. However, the factors explaining the observed changes in the incidence of WNV in Europe are not completely understood. Longitudinal monitoring of WNV in wild animals across Europe is a useful approach to understand the eco-epidemiology of WNV in the wild and the risk of spillover into humans.

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Introduction: West Nile virus (WNV) and Usutu virus (USUV) are emerging zoonotic arboviruses sharing the same life cycle with mosquitoes as vectors and wild birds as reservoir hosts. The main objective of this study was to characterize the pathogenicity and course of infection of two viral strains (WNV/08 and USUV/09) co-circulating in Southern Spain in a natural host, the red-legged partridge (), and to compare the results with those obtained with the reference strain WNV/NY99.

Methods: WNV inoculated birds were monitored for clinical and analytical parameters (viral load, viremia, and antibodies) for 15 days post-inoculation.

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West Nile virus (WNV) is a mosquito-borne pathogen that belongs to the genus (family ) [...

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West Nile virus (WNV) transmission rate is shaped by the interaction between virus reservoirs and vectors, which may be maximized in farm environments. Based on this hypothesis, we screened for WNV in wild birds in three scenarios with decreasing gradient of interaction with horses: (i) the farm (A); (ii) the neighborhood (A); and (iii) a wild area (A). We captured wild birds and analyzed their sera for WNV antibodies by blocking ELISA and micro-virus neutralization test.

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Article Synopsis
  • - Reports of West Nile virus (WNV) disease in humans were rare in Spain until the summer of 2020, when 77 cases were confirmed, eight of which were fatal, primarily occurring near the Guadalquivir River in two Sevillian villages.
  • - The emergence of human cases coincided with a significant rise in WNV-infected mosquitoes, with the first detections of infected mosquitoes occurring about a month prior to the first reported human infections.
  • - Evidence from wild bird serology indicated the circulation of WNV in the affected areas and highlighted that blackbirds may have played a crucial role in amplifying the virus, while ongoing surveillance of mosquitoes could help detect WNV before human outbreaks occur.
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Better understanding on interactions between SARS-CoV-2 and host cells should help to identify host factors that may be targetable to combat infection and COVID-19 pathology. To this end, we have conducted a genome-wide CRISPR/Cas9-based loss-of-function screen in human lung cancer cells infected with SARS-CoV-2-pseudotyped lentiviruses. Our results recapitulate many findings from previous screens that used full SARS-CoV-2 viruses, but also unveil two novel critical host factors: the lysosomal efflux transporter SPNS1 and the plasma and lysosomal membrane protein PLAC8.

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Article Synopsis
  • - The study aimed to compare the effectiveness of oral saliva swab (OSS) RT-PCR testing for SARS-CoV-2 against traditional nasopharyngeal swabs (NPS) and rapid antigen tests in children showing COVID-19 symptoms.
  • - Conducted across 10 hospitals in Spain, the research involved 1,174 children aged 0 to 18, with results indicating that OSS RT-PCR has a sensitivity of 72.1% and a specificity of 99.6%, making it a reliable testing method.
  • - The findings suggest that using OSS for COVID-19 testing in children could be a less invasive and therefore more acceptable method, potentially leading to increased testing rates among younger patients.
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Article Synopsis
  • West Nile virus lineage 2 (WNV-L2) emerged in Europe in 2004 and has spread widely, causing outbreaks in humans and animals, notably detected in northern goshawks in Catalonia, Spain.
  • Researchers conducted genome sequencing and phylogenetic analyses, revealing that Spanish WNV-L2 isolates are related to a cluster that originated in Italy and have shown moderate to high virulence in laboratory studies.
  • These findings indicate that WNV-L2 can overwinter and circulate in the region, highlighting the need for increased surveillance due to rising cases in both humans and animals across Europe.
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  • Crimean-Congo haemorrhagic fever (CCHF) is a tick-borne virus found in over 57 countries, with a focus on identifying its presence in livestock for human health risks.
  • A study in Bosnia and Herzegovina tested 176 sheep for CCHFV antibodies, revealing that 17 (9.66%) showed positive results.
  • This marks the first detection of CCHFV antibodies in sheep in B&H, suggesting the virus may be circulating in the area and potentially spreading beyond its known endemic regions in the Balkans.
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The surveillance for West Nile virus (WNV) in Catalonia (northeastern Spain) has consistently detected flaviviruses not identified as WNV. With the aim of characterizing the flaviviruses circulating in Catalonia, serum samples from birds and horses collected between 2010 and 2019 and positive by panflavivirus competition ELISA (cELISA) were analyzed by microneutralization test (MNT) against different flaviviruses. A third of the samples tested were inconclusive by MNT, highlighting the limitations of current diagnostic techniques.

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Background: The fight against the current coronavirus disease 2019 (COVID-19) pandemic has created a huge demand of biotechnological, pharmaceutical, research and sanitary materials at unprecedented scales. One of the most urgent demands affects the diagnostic tests. The growing need for rapid and accurate laboratory diagnostic tests requires the development of biotechnological processes aimed at producing reagents able to cope with this demand in a scalable, cost-effective manner, with rapid turnaround times.

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West Nile virus (WNV) is the most widespread flavivirus in the world with a wide vertebrate host range. Its geographic expansion and activity continue to increase with important human and equine outbreaks and local bird mortality. In a previous experiment, we demonstrated the susceptibility of 7-week-old red-legged partridges () to Mediterranean WNV isolates Morocco/2003 and Spain/2007, which varied in virulence for this gallinaceous species.

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The Dilution Effect Hypothesis (DEH) argues that greater biodiversity lowers the risk of disease and reduces the rates of pathogen transmission since more diverse communities harbour fewer competent hosts for any given pathogen, thereby reducing host exposure to the pathogen. DEH is expected to operate most intensely in vector-borne pathogens and when species-rich communities are not associated with increased host density. Overall, dilution will occur if greater species diversity leads to a lower contact rate between infected vectors and susceptible hosts, and between infected hosts and susceptible vectors.

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Before this report, 7 autochthonous human cases of Crimean-Congo hemorrhagic fever had been reported in Spain, all occurring since 2016. We describe the retrospective identification of an eighth case dating back to 2013. This study highlights that the earliest cases of an emerging disease are often difficult to recognize.

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West Nile virus (WNV) is an emerging flavivirus transmitted generally by mosquitoes of Culex genus. It is maintained in an enzootic life cycle where birds act as reservoir hosts. Humans and horses are also susceptible to infection, and occasionally, they suffer from neurological complications.

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The increasing incidence of West Nile virus (WNV) in the Euro-Mediterranean area warrants the implementation of effective surveillance programs in animals. A crucial step in the fight against the disease is the evaluation of the capacity of the veterinary labs to accurately detect the infection in animal populations. In this context, the animal virology network of the MediLabSecure project organized an external quality assessment (EQA) to evaluate the WNV molecular and serological diagnostic capacities of beneficiary veterinary labs.

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Rift Valley fever (RVF) is an arboviral zoonosis that primarily affects ruminants but can also cause illness in humans. The increasing impact of RVF in Africa and Middle East and the risk of expansion to other areas such as Europe, where competent mosquitos are already established, require the implementation of efficient surveillance programs in animal populations. For that, it is pivotal to regularly assess the performance of existing diagnostic tests and to evaluate the capacity of veterinary labs of endemic and non-endemic countries to detect the infection in an accurate and timely manner.

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West Nile virus (WNV) is a mosquito-borne emerging virus in Europe with capacity to cause neurological complications such as encephalitis or meningoencephalitis in humans, birds or equids. In Spain, WNV is actively circulating in mosquitoes, birds and horses in different regions, but never has been deeply studied in Extremadura. Therefore, the aim of this study was to evaluate the seroprevalence of WNV in equids of those areas and to analyse the risk factors associated with exposure to the virus.

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Vector-borne diseases, especially those transmitted by mosquitoes, have severe impacts on public health and economy. West Nile virus (WNV) and avian malaria parasites of the genus Plasmodium are mosquito-borne pathogens that may produce severe disease and illness in humans and birds, respectively, and circulate in an endemic form in southern Europe. Here, we used field-collected data to identify the impact of Culex pipiens, Cx.

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