Publications by authors named "Valeria Gayo"

We report the genomic analysis from early equine cases of the Western equine encephalitis virus outbreak during 2023-2024 in Uruguay. Sequences are related to a viral isolate from an outbreak in 1958 in Argentina. A viral origin from South America or continuous enzootic circulation with infrequent spillover is possible.

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Here, we describe a spontaneous outbreak of strongyloidiasis (Strongyloides papillosus) in sheep in Uruguay. In a flock of 150 lambs, 60 animals became ill and 12 died within 3 weeks. Affected animals showed weakness, weight loss, enophthalmos and, in some cases, sudden death.

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Fasciola hepatica has a heteroxenous complex life cycle that alternates between an invertebrate intermediate and a mammalian definitive host. The life cycle has five well-defined phases within their hosts and the environment: (1) eggs released from the vertebrate host to the environment and its subsequent development; (2) emergence of miracidia and their search and penetration into an intermediate snail host; (3) development and multiplication of larval stages within the snail; (4) emergence of cercariae and the encystment in metacercariae; and (5) ingestion of infective metacercariae by the definitive host and development to its adult form. Here we describe some protocols to obtain and maintain different developmental stages of F.

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Background: Fasciola hepatica is the main agent of fasciolosis, a zoonotic disease affecting livestock worldwide, and an emerging food-borne disease in humans. Even when effective treatments are available, drugs are costly and can result in tolerance, liver damage and normally they do not prevent reinfection. Drug-resistant strains in livestock have been reported in various countries and, more worryingly, drug resistance in human cases has emerged in South America.

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Background: Fascioliasis is a pathogenic disease transmitted by lymnaeid snails and recently emerging in humans, in part due to effects of climate changes, anthropogenic environment modifications, import/export and movements of livestock. South America is the continent presenting more human fascioliasis hyperendemic areas and the highest prevalences and intensities known. These scenarios appear mainly linked to altitude areas in Andean countries, whereas lowland areas of non-Andean countries, such as Uruguay, only show sporadic human cases or outbreaks.

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Fasciola hepatica M17 leucine aminopeptidase (FhLAP) is thought to play a role in catabolizing peptides generated by the concerted activity of gut-associated endopeptidases on host polypeptides, thus releasing amino acids to be used in protein anabolism. In this study, a recombinant functional form of this homo hexameric metallopeptidase produced in Escherichia coli was used in combination with adjuvants of different types in a vaccination trial in Corriedale sheep against experimental challenge with F. hepatica metacercariae.

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Fascioliasis, the zoonotic disease caused by the trematode Fasciola hepatica, is expanding worldwide, with a 17 million people at risk. Rodents, often recognized as a major source of zoonotic diseases, are affected by F. hepatica, with some species playing important roles in the disease epidemiology.

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