Lessons from a Multilaboratorial Task Force for Diagnosis of a Fatal Toxoplasmosis Outbreak in Captive Primates in Brazil.

Toxoplasmosis is an important zoonotic disease caused by the parasite Toxoplasma gondii and is especially fatal for neotropical primates. In Brazil, the Ministry of Health is responsible for national epizootic surveillance, but some diseases are still neglected. Here, we present an integrated investigation of an outbreak that occurred during the first year of the COVID-19 pandemic among eleven neotropical primates housed at a primatology center in Brazil. After presenting non-specific clinical signs, all animals died within four days. A wide range of pathogens were evaluated, and we successfully identified T. gondii as the causative agent within four days after necropsies. The liver was the most affected organ, presenting hemorrhage and hepatocellular necrosis. Tachyzoites and bradyzoite cysts were observed in histological examinations and immunohistochemistry in different organs; in addition, parasitic DNA was detected through PCR in blood samples from all specimens evaluated. A high prevalence of Escherichia coli was also observed, indicating sepsis. This case highlights some of the obstacles faced by the current Brazilian surveillance system. A diagnosis was obtained through the integrated action of researchers since investigation for toxoplasmosis is currently absent in national guidelines. An interdisciplinary investigation could be a possible model for future epizootic investigations in animals.

Persistent SARS-CoV-2 antigen presence in multiple organs of a naturally infected cat from Brazil

Abstract Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the etiological agent of the disease coronavirus 2019 (COVID-19) in humans. SARS-CoV-2 has been identified in cats with or without clinical signs. Case presentation: We describe the pathological and molecular findings in a six-month-old asymptomatic cat with SARS-CoV-2 infection from Brazil, belonging to a human family with COVID-19 cases. The pool of nasopharynx and oropharynx swabs at day zero tested positive by RT-qPCR for SARS-CoV-2. No amplification resulted from molecular testing performed on days 7 and 14. The cat was hit by a car and died 43 days after the molecular diagnosis. Immunohistochemistry at post-mortem examination demonstrated nucleocapsid protein in samples from the lungs, kidneys, nasal conchae, trachea, intestine, brain and spleen. Conclusion: The present study has highlighted the possibility that viral antigens can be detected by immunohistochemistry in multiple organs six weeks after infection, although the same tissues tested negative by RT-PCR.

Persistent SARS-CoV-2 antigen presence in multiple organs of a naturally infected cat from Brazil

Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the etiological agent of the disease coronavirus 2019 (COVID-19) in humans. SARS-CoV-2 has been identified in cats with or without clinical signs. Case presentation: We describe the pathological and molecular findings in a six-month-old asymptomatic cat with SARS-CoV-2 infection from Brazil, belonging to a human family with COVID-19 cases. The pool of nasopharynx and oropharynx swabs at day zero tested positive by RT-qPCR for SARS-CoV-2. No amplification resulted from molecular testing performed on days 7 and 14. The cat was hit by a car and died 43 days after the molecular diagnosis. Immunohistochemistry at post-mortem examination demonstrated nucleocapsid protein in samples from the lungs, kidneys, nasal conchae, trachea, intestine, brain and spleen. Conclusion: The present study has highlighted the possibility that viral antigens can be detected by immunohistochemistry in multiple organs six weeks after infection, although the same tissues tested negative by RT-PCR.(AU)

Toxoplasma gondii induced abortions in a goat herd in Rio de Janeiro, Brazil / Aborto por Toxoplasma gondii em um rebanho de caprinos no estado do Rio de Janeiro, Brasil

ABSTRACT: Although, serological assays for detecting immune response against Toxoplasma gondii in goats and sheep are frequent in Brazil, studies showing lesions and confirmation of infectious causes of abortion in goats in the state of Rio de Janeiro have not been reported. This study aimed to describe an abortion outbreak caused by T. gondii in a goat herd in the state of Rio de Janeiro. At histological examination, necrotizing encephalitis and lymphoplasmacytic myositis were observed in goat fetuses submitted to necropsy. The diagnoses were confirmed by immunohistochemistry, which revealed positive marking structures compatible with T. gondii bradyzoites in the brain and skeletal muscle cysts. T. gondii should be included among the causes of abortion in goats in the Southeast region of Brazil.

RESUMO: Embora sejam frequentes as pesquisas sorológicas da toxoplasmose em caprinos e ovinos no Brasil, os estudos que apresentam as lesões e a confirmação das causas infecciosas de aborto em caprinos no estado do Rio de Janeiro não foram encontrados. Neste trabalho descreve-se Toxoplasma gondii como causa de aborto em uma criação de caprinos no estado do Rio de Janeiro. Ao exame histológico foi observada encefalite necrosante e miosite linfoplasmocítica nos fetos caprinos submetidos à necropsia. A confirmação do diagnóstico foi realizada com o exame de imuno-histoquímica, que revelou marcação positiva de cistos com bradizoítos de T. gondii no encéfalo e em músculo esquelético. T. gondii deve ser incluído entre as causas de aborto em cabras na região sudeste do Brasil.