The objectives of the present work were to screen topsoil samples collected from public squares in two cities within the Argentine Patagonia for the presence of infective forms of intestinal parasites and to examine the possible relationship between positive findings and the environmental, socioeconomic, and cultural conditions of that region. For this purpose we studied 13 public squares, their 13 custodians, and 44 family groups within their respective surrounding areas. Of the 226 topsoil samples analyzed, 44.3% proved positive for infective forms of intestinal parasites, with 17.3% of these containing more than one species. The frequency of appearance of positive samples was dependent on the season of the year (p < 0.001), while presence of the parasites was related to the soil pH (p < 0.05) but independent of the soil relative humidity (p > 0.05). Some of the organisms detected are associated with zoonoses. We observed the presence of Capillaria spp. and Spirocerca spp. under cool desert climatic conditions. Within the group of custodians we detected hematologic alterations one positive serology for toxoplasmosis and documented behavior conducive to risk of infection with the parasites found in those squares. Within the family group an acquaintance with parasitic zoonoses and their prevention was an inconsistent finding, with toxocarosis and toxoplasmosis being the diseases associated with the greatest degree of ignorance. Furthermore, we consider the failure to de-parasitize pets and the practice of feeding them with raw meat, as typically found in our family survey, to be factors contributing to a greater likelihood of public square contamination. From the results obtained here, we propose a spatial organization approach for the purpose of detecting zones at risk of contracting zoonotic parasitoses within urban environments.

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A longitudinal study to determine the presence of intestinal parasites in canine faeces

Cystic echinococcosis caused by Echinococcus granulosus is a major zoonosis of public health significance in the Patagonian region of Argentina. This investigation sought to test the hypothesis that the persistence and dispersion of the parasite eggs can be explained by physical and meteorological parameters along with final host infection and behaviour. This observational study was carried out over a five-year period within an enclosure where two dogs harbouring a worm burden ranging from 100 to 1000 mature adult E. granulosus, as well as two uninfected dogs, had previously been kept for six months. Environmental canine faeces, topsoil, pond water, and sediment samples were examined to control for the presence of eggs and coproantigens of the parasite using microscope-based techniques and copro-ELISA plus copro-Western Blot tests. The parasite eggs were detected up to 41 months later in faeces from infected dogs, soil and sediment, and coproantigen tests remained positive for up to 70 months in faeces. Overall, parasite eggs were found within a maximum distance of 115 m from the contaminated dog faeces deposition site. Our findings indicate that under Patagonian environmental conditions, egg persistence and dispersion seem to be related to the worm burden and habits of the infected dog, to prevailing wind direction and to the existence of low bushes as well as natural bodies of water. The present study is the first to provide direct evidence of interaction between bioclimatic conditions and E. granulosus egg dispersion under Patagonian field conditions. https://www.cambridge.org/core/terms. https://doi.

Blue mussels (Mytilus edulis) are among the most consumed fishery products globally. Foodborne outbreaks of mussel-associated infections by viral, bacterial, and parasitic pathogens have been reported in the last years. In this study, we investigated the occurrence, genetic diversity, and zoonotic potential of the diarrhea-causing enteric protozoan Giardia duodenalis in blue mussels from Caleta Co ´rdova in Chubut Province, southeast Patagonia, Argentina. A total of 344 free-living blue mussels were collected and distributed in 53 aliquots of pooled mussel tissue (each containing 5-7 specimens) during the period 2015-2018. Conventional optical microscopy was used as screening method for the detection of G. duodenalis cysts in pooled, homogenized tissues. Samples with a positive result were assessed by a multilocus sequence genotyping scheme based on the amplification of partial fragments of the glutamate dehydrogenase and b-giardin genes of the parasite. G. duodenalis cysts were found in 30.2% (16/53) of the aliquots of pooled mussel tissue tested. PCR and sequencing analyses revealed the presence of G. duodenalis subassemblage BIV in selected aliquots. To the best of our knowledge, this is the first description of zoonotic subassemblage BIV from blue mussels in Argentina.