Toxoplasma gondii infection in European brown hares (Lepus europaeus) in Brazil.

Toxoplasmosis is a worldwide zoonosis that affects warm-blooded animals, including humans. Wild animals can act as intermediate hosts of this pathogen; thus, this study aims to detect Toxoplasma gondii infection in invasive European brown hares in Brazil. For this, 72 wild European brown hares were captured from July 2020 to June 2022 in three Brazilian states: São Paulo, Paraná, and Rio Grande do Sul. The diagnostic of Toxoplasma gondii infection was performed by bioassay in mouse, histopathology in Hematoxylin-Eosin-stained tissue sections (brain, liver, lungs, kidneys, and small intestine), serology by IFAT, and molecular techniques by conventional PCR and qPCR. The combined prevalence of the different diagnostic methods was 51.4% (37/72, CI= 40.1 - 62.6 %), and there was no statistical difference between sexes, age range, or geographical region of the hosts. Mouse bioassay was the technique that detected more positive hares. To our knowledge, this is the first confirmation of Toxoplasma gondii infection in invasive European brown hares in Brazil. These animals act as reservoirs and potential infection source for carnivores and other wild and domestic animals, including humans, thus contributing to perpetuate the disease cycle in São Paulo, Paraná, and Rio Grande do Sul States. Research such as the present study is necessary to raise awareness about the role of animals in the disease cycle.

The Brazilian Toxoplasma gondii strain BRI caused greater inflammation and impairment in anxiogenic behavior in mice, which was reverted by rosuvastatin treatment.

This study aimed to investigate the effect of rosuvastatin treatment on anxiety-related behavior and short- and long-term memory impairment in mice infected with acute RH and BRI strains of Toxoplasma gondii. Balb/C mice were infected intraperitoneally and after 2 h, oral treatment with rosuvastatin (40 mg/kg/day) was initiated for 4 days. Behaviors related to anxiety and locomotion were evaluated in the open field (OF), and short- and long-term memory through the novel object recognition test (NOR). At the end of the experiments, peritoneal fluid, brain, liver, and lung were collected for T. gondii DNA quantification and histopathological analysis. Infection with BRI strain reduced the dwell time and central locomotion in the OF (p < 0.05), indicating anxiogenic type behavior, while treatment with rosuvastatin reversed this response (p < 0.05). RH strain infection did not alter any behavior in the OF (p > 0.05) and both strains impaired short- and long-term memory (NOR test), but with no significant treatment effect (p > 0.05). The BRI strain was shown to be more damaging in relation to anxiogenic type behavior when compared to the RH strain (p < 0.05), whereas rosuvastatin reduced this damaging effect in BRI. The treatment reduced the parasite load in the peritoneal lavage, liver, and lung of animals infected with both acute strains; however, it significantly (p < 0.05) attenuated the inflammatory process only in BRI-infected and treated animals, showing that non-archetypal genotypes are more damaging in rodents. This suggests that rosuvastatin may be a drug with great therapeutic potential against T. gondii mainly to reduce damage from virulent strains.

High occurrence of viable forms of Cryptosporidium and Giardia in domestic sewage from an agricultural region of Brazil.

Cryptosporidium and Giardia are the main etiologies of waterborne outbreaks caused by protozoa. These parasites are commonly detected in wastewater; however, there is little knowledge about the concentration of viable forms in treated sewage, mainly in small communities. To understand more about the presence of viable oocysts and cysts in domestic sewage, we monitored the affluent and effluent of a wastewater treatment plant (WWTP) in inner-city Brazil. Ten samplings and seven follow-ups were performed in 2020. Samples were concentrated by centrifugation, filtration and purified by fluctuation. Viability was accessed by propidium-monoazide (PMA) associated with nPCR and qPCR. Both viable protozoa were detected in all raw sewage samples (average: 438.5 viable oocysts/L). Regarding treated sewage, Cryptosporidium was detected in all of the samples (average: 92.8 viable oocysts/L) and Giardia was detected in 70% with viable cysts in 30%. Considering the follow-ups, 31.17% of Cryptosporidium viable oocysts remained in the effluent after the treatment. High amounts of Cryptosporidium and a high frequency of Giardia were detected, therefore both arrived at WWTP and were discharged into the river. These alert the presence of agro-industrial effluents into domestic sewage and demonstrated the effectiveness of the concentration technique for monitoring protozoa in wastewater.