Features of clinical and pathomorphological picture in spontaneous infection of a domestic cat (lat. Félis cátus) with SARS-CoV-2 coronavirus

Abstract

Today, cases of infection of various animal species with the new SARS-CoV-2 coronavirus have become increasingly common. This virus has been isolated from numerous representatives of the feline family, European mink, ferret, raccoon dog, domestic dog, a number of primates and a number of other animals. In most susceptible animals, infection with this virus is manifested by certain clinical symptoms, the intensity of which depends on the type and age of the animals, on the presence of concomitant diseases. The pathological process can end in death with the development of characteristic pathoanatomical and histological changes. According to the results of preliminary studies conducted in the Republic of Belarus, the circulation of SARS-CoV-2 was detected in domestic cats. All the animals had a history of contact with COVID-19-infected owners. The aim of this work was to determine the features of clinical and pathoanatomical manifestations, histological changes in domestic cats infected with SARS-CoV-2. The studies were conducted among various sex and age groups of domestic cats. In total, we conducted a study of 300 flushes from various sexes and ages and pedigreed, autopsy of 10 corpses. The work was carried out in the Vitebsk State Academy of Veterinary Medicine, the Vitebsk Regional Veterinary Laboratory, the RSPC "Epidemiology and Microbiology" in Minsk, in the Belarusian State Veterinary Center. The circulation of SARS-CoV-2 in animals was determined by polymerase chain reaction (RT - PCR). When dissecting the corpses of animals, the nature and severity of pathomorphological changes were taken into account, a pathoanatomical diagnosis was made, and macrophotography was performed in natural light. The main clinical symptoms of the disease in adult animals are depression, refusal to feed, cough, shortness of breath; in young animals, rhinitis, conjunctivitis, diarrhea are often observed. When dissecting dead animals, macro-changes and micro-changes in organs and tissues are noted, indicating the development of pathological processes, both in the acute course of the disease and in the chronic one. Thus, the conducted studies and the results obtained confirmed and supplemented the data of world researchers, made it possible to determine the leading clinical symptoms of the disease and pathoanatomical changes in the domestic cat when infected with SARS-CoV-2. The obtained data of histological changes allowed a deeper and more detailed assessment and study of the pathogenesis of the disease, which will contribute to a rational approach in choosing the means of therapy of this disease. Key words: cats, coronavirus, SARS-CoV-2, clinical symptoms, pathoanatomical changes, histological examination.

Cats and SARS-CoV-2: A Scoping Review

“…The duration of clinical symptoms reported in the different studies varied greatly from a few days to a few weeks. The longest duration of symptoms was recorded by Natale et al [ 32 ], who reported 2 weeks of symptoms in one case and Subotsina et al Subotsina, Gromov and Kupryianav [ 38 ], who found an average symptom duration of 2–3 weeks in 15 examined cases.…”

“…Brandão et al [ 19 ], Fritz et al [ 50 ], and Gargliany et al [ 47 ] generically reported respiratory symptoms, while Neira et al [ 33 ], Pagani et al [ 34 ], and Zoccola et al [ 42 ] reported mild respiratory symptoms. Other studies more specifically described sneezing, coughing, and/or shortness of breath [ 27 , 28 , 38 , 44 ]. Some cats developed symptoms of pneumonia.…”

“…Non-respiratory symptoms that were reported in different case studies included: Gastrointestinal symptoms [ 32 , 38 , 47 ], cardiac abnormalities [ 22 ], inappetence and apathy [ 28 , 38 ], ocular discharge [ 27 , 38 ], and fever [ 26 , 38 ]. …”

“…Chiba et al [ 45 ] also found mild bronchiolitis in infected cats and while infectious virus cleared from lungs within six days after initial infection, lung lesions persisted at least until a month after infection. Next to these experimental studies, there was also a big case series investigating the clinical and pathomorphological picture in 15 symptomatic cats with natural SARS-CoV-2 infection in Belarus [ 38 ]. The main pathoanatomical changes found here were membranogenic pulmonary edema, pronounced blood clotting in medium-sized blood vessels, and the expansion of the heart chambers and pulmonary vein system, while the main histological features were lymphoid-macrophage peribronchitis and perivasculitis.…”

“…A second relation commonly researched was the relation between humans and cats with regard to SARS-CoV-2. Most of the studies included in this review were case studies that reported different cases of the natural human-to-cat transmission of SARS-CoV-2 [ 11 , 18 , 21 , 22 , 27 , 28 , 33 , 34 , 35 , 38 , 42 , 44 , 48 , 50 ]. In many of these studies, the hypothesis of owner-to-cat transmission was underlined through sequencing of the viral genome from both the owner and cat.…”