Case report: Urbanized non-human primates as sentinels for human zoonotic diseases: a case of acute fatal toxoplasmosis in a free-ranging marmoset in coinfection with yellow fever virus.

Free-ranging non-human primates (NHP) can live in anthropized areas or urban environments in close contact with human populations. This condition can enable the emergence and transmission of high-impact zoonotic pathogens. For the first time, we detected a coinfection of the yellow fever (YF) virus with Toxoplasma gondii in a free-ranging NHP in a highly urbanized area of a metropolis in Brazil. Specifically, we observed this coinfection in a black-tufted marmoset found dead and taken for a necropsy by the local health surveillance service. After conducting an epidemiological investigation, characterizing the pathological features, and performing molecular assays, we confirmed that the marmoset developed an acute fatal infection caused by T. gondii in coinfection with a new YF virus South American-1 sub-lineage. As a result, we have raised concerns about the public health implications of these findings and discussed the importance of diagnosis and surveillance of zoonotic agents in urbanized NHPs. As competent hosts of zoonotic diseases such as YF and environmental sentinels for toxoplasmosis, NHPs play a crucial role in the One Health framework to predict and prevent the emergence of dangerous human pathogens.

Fatal traumatic injuries in free-living wild Passeriformes and Psittaciformes birds in Central Brazil, 2006-2018 / Injúrias traumáticas fatais em aves Passeriformes e Psittaciformes no Brasil Central, 2006-2018

Traumatic injuries are a significant cause of death for birds worldwide, as they are at an increased risk of collisions and other injuries due to man-made environments. This study examined the frequency and morphological characteristics of fatal traumatic injuries in endemic and migratory Passeriformes and Psittaciformes from the Cerrado Biome, a biodiverse but threatened area in Brazil. Results showed that fatal traumatic injuries were found in 21.8% of birds (285/1305), mainly in spring and summer, during the birds' reproductive period. The yellow-chevroned parakeet (Brotogeris chiriri) and Passeriformes from the Thraupidae family were the most affected. Nearly 70% of the fatal injuries observed were to the thoracic, pelvic limbs, and skull, and types of fractures and affected bones were thoroughly evaluated. Blunt traumas were one of the most frequent causes of injuries. Injuries affecting the appendicular skeleton and head represented significant causes of traumatic death for Passeriformes and Psittaciformes. The frequency of these fatal injuries has been increasing in recent years, which may be related to the remarkable environmental changes in the Cerrado Biome and jeopardize the survival of many bird species.

As lesões traumáticas são uma causa significativa de morte nas aves em todo o mundo, pois apresentam um risco maior de colisões e outras lesões devido aos ambientes degradados e criados pelo homem. Este estudo examinou a frequência e as características morfológicas das lesões traumáticas fatais em Passeriformes e Psittaciformes endêmicos e migratórios do Bioma Cerrado, uma área com rica biodiversidade, mas ameaçada no Brasil. Os resultados demostraram que as lesões traumáticas fatais foram observadas em 21,8% das aves (285/1305), principalmente na primavera e verão, durante a época reprodutiva das aves. O periquito-do-encontro-amarelo (Brotogeris chiriri) e Passeriformes da família Thraupidae foram as aves mais frequentemente acometidas. Por volta de 70% das lesões fatais observadas foram nos membros torácicos e pélvicos, e crânio, e os tipos de fraturas e ossos afetados foram minuciosamente avaliados. Os traumas contudentes foram as principais causas das lesões. As injúrias que afetaram o esqueleto apendicular e a cabeça representaram as mais importantes causas de morte traumática para Passeriformes e Psittaciformes. A frequência dessas lesões fatais vem aumentando nos últimos anos, o que pode estar relacionado às mudanças ambientais marcantes no Bioma Cerrado e colocar em risco a sobrevivência de muitas espécies de aves.

Hepato-pathological hallmarks for the surveillance of Yellow Fever in South American non-human primates.

The early detection and diagnosis of deaths in free-ranging non-human primates (NHPs) are key points for the surveillance of Yellow Fever (YF) in Brazil. The histopathological identification of infectious diseases remains very useful and reliable in the screening and detection of emerging zoonotic diseases such as YF. We surveyed data records and liver slides stained with hematoxylin and eosin from the Epizootics Surveillance Network to control YF, Ministry of Health of Brazil, to evaluate histopathological hallmarks for the diagnosis of the YF virus infection. We selected natural fatal cases in NHPs from the genera Alouatta spp., Callithrix spp., and Sapajus spp. with a positive immunohistochemical assay for YF in liver samples. Our findings showed the full-spectrum YF-associated hepatic lesions in all NHPs, but some histopathological findings differed in the distribution and intensity between the three genera. In our study, South American NHPs showed significant differences in the YF-associated hepatic histopathological features compared to fatal cases reported in humans.

Fatal Human Alphaherpesvirus 1 Infection in Free-Ranging Black-Tufted Marmosets in Anthropized Environments, Brazil, 2012-2019.

Human alphaherpesvirus 1 (HuAHV1) causes fatal neurologic infections in captive New World primates. To determine risks for interspecies transmission, we examined data for 13 free-ranging, black-tufted marmosets (Callithrix penicillata) that died of HuAHV1 infection and had been in close contact with humans in anthropized areas in Brazil during 2012-2019. We evaluated pathologic changes in the marmosets, localized virus and antigen, and assessed epidemiologic features. The main clinical findings were neurologic signs, necrotizing meningoencephalitis, and ulcerative glossitis; 1 animal had necrotizing hepatitis. Transmission electron microscopy revealed intranuclear herpetic inclusions, and immunostaining revealed HuAHV1 and herpesvirus particles in neurons, glial cells, tongue mucosal epithelium, and hepatocytes. PCR confirmed HuAHV1 infection. These findings illustrate how disruption of the One Health equilibrium in anthropized environments poses risks for interspecies virus transmission with potential spillover not only from animals to humans but also from humans to free-ranging nonhuman primates or other animals.

Pathology in Practice.

In collaboration with the American College of Veterinary Pathologists.

Endemic Xanthium strumarium poisoning in cattle in flooded areas of the Araguari River, Minas Gerais, Brazil.

In this paper, we describe poisoning outbreaks of Xanthium strumarium in cattle on the borders of the Araguari River, Southeastern Brazil. In this region, several hydroelectric plants promote transient flooding, which creates a favorable environment for the invasion of X. strumarium in extensive areas, often as the predominant species in those areas. The outbreaks occurred between July and September (dry season). Bovines of all ages were affected, including suckling animals. Mortality varied from 2% to 5.5%. The animals exhibited ataxia, weakness, loss of balance, recumbency, and the majority were found dead. Laboratory results showed a marked increase in the serum activities of alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and gamma-glutamyltransferase. Histological and ultrastructural changes in the liver consisted of centrilobular necrosis and hemorrhage. On toxicological evaluation, the dicotyledons contained 0.30 µg/mg of atractyloside and 0.37 µg/mg of carboxyatractyloside. Considerable economic loss has occurred in this region due to the lack of knowledge regarding X. strumarium as a toxic plant and its adaptation to the environmental and climatic conditions of the region, which have made the condition endemic.

Uraemic Encephalopathy in a Persian Cat with Chronic Kidney Disease.

Uraemic encephalopathy (UE) is rarely associated with acute kidney injury or chronic kidney disease in domestic animals, and we now report the first case in a cat. The animal presented with hypothermia, apathy, lethargy, depression, severe dehydration, uraemic breath, elevated serum urea nitrogen and creatine concentrations, and eventual seizures and coma prior to death. Gross necropsy findings included severe bilateral renal scarring, ulcerative stomatitis and glossitis, and uraemic gastropathy. Microscopic lesions of diffuse interstitial fibrosis, multifocal mineralization and lymphoplasmacytic interstitial nephritis were seen in the kidneys. There was symmetrical, bilateral spongy vacuolation of the white matter of the basal nuclei and cerebellum and Alzheimer type II astrocytes in the cerebral cortex and hippocampus. Glial fibrillary acid protein immunolabelling was absent or faint in astrocytes of the cerebral grey matter. UE should be included in the differential diagnosis in animals with chronic kidney disease and neurological signs.

Pulmonary actinomycosis in a free-living black-tufted marmoset (Callithrix penicillata).

Actinomycosis is a very rare infection in wild animals with a few reports in captive non-human primates. Herein we report a case of pulmonary actinomycosis in a free-living black-tufted marmoset in the urban area of the Federal District, Brazil. The animal presented severe dyspnea and died in the garden of a residence. At necropsy, the left-pulmonary lobes showed multiple nodules filled with purulent content. A myriad of beaded, branching, filamentous Gram-positive and modified Ziehl-Neelsen-negative bacilli arranged in aggregates or star-like colonies, surrounded by macrophages, neutrophils, and Splendori-Hoepli phenomenon were observed in histological sections of the lungs. According to the pathological findings and characteristic morphotintorial pattern of the infectious agent, pulmonary actinomycosis was diagnosed. Until now, fatal pulmonary actinomycosis had never been reported in free-living Simiiformes. Knowledge about the diseases that affect commensal free-range simians in urban areas forms the basis for actions aimed at conservation of the species.