The Upper Respiratory Tract of Felids Is Highly Susceptible to SARS-CoV-2 Infection

Abstract

Natural or experimental infection of domestic cats and virus transmission from humans to captive predatory cats suggest that felids are highly susceptible to SARS-CoV-2 infection. However, it is unclear which cells and compartments of the respiratory tract are infected. To address this question, primary cell cultures derived from the nose, trachea, and lungs of cat and lion were inoculated with SARS-CoV-2. Strong viral replication was observed for nasal mucosa explants and tracheal air–liquid interface cultures, whereas replication in lung slices was less efficient. Infection was mainly restricted to epithelial cells and did not cause major pathological changes. Detection of high ACE2 levels in the nose and trachea but not lung further suggests that susceptibility of feline tissues to SARS-CoV-2 correlates with ACE2 expression. Collectively, this study demonstrates that SARS-CoV-2 can efficiently replicate in the feline upper respiratory tract ex vivo and thus highlights the risk of SARS-CoV-2 spillover from humans to felids.

An Overview of Epithelial-to-Mesenchymal Transition and Mesenchymal-to-Epithelial Transition in Canine Tumors: How Far Have We Come?

“…Another study suggested that the SARS-CoV-2 M protein induces motility, proliferation, stemness, and in vivo metastasis of triple-negative breast cancer [ 111 ]. Despite studies reporting that SARS-CoV-2 could also infect felids [ 113 ], dogs [ 114 ], and many other domestic species [ 115 ], reports on dogs or other pets exhibiting a SARS-CoV-2-induced EMT process are still lacking.…”

Elevated angiotensin-converting enzyme 2 (ACE2) expression in cats with hypertrophic cardiomyopathy

“…Most of these cases do not present clinical signs or only display with mild upper respiratory clinical signs (Barroso-Arévalo et al, 2022;Hosie et al, 2021;Klaus et al, 2021). Generally, the susceptibility of cats to SARS-CoV-2 infection is thought to be related to the expression of cognate viral receptor ACE2 in the upper respiratory tract (Färber et al, 2022;Gerhards et al, 2021;Krüger et al, 2021;Lean et al, 2021). Similar observations have also been made from in vivo modelling of SARS-CoV-2 infection in cats (Bosco-Lauth et al, 2020;Gaudreault et al, 2020).…”

SARS-CoV-2 Infection in Captive Hippos (Hippopotamus amphibius), Belgium

“…Why only nasal discharge was present without other signs of respiratory infection could be due to the difference in the receptor ACE2 expression across tissues, as in lion, cheetah and lynx [28]. While recognition of the receptor ACE2 is a key determining factor for cross-species infection of SARS-CoV-2, the transmembrane serine protease 2 (TMPRSS2) is also important to cleave the spike protein and facilitate viral-host membrane fusion.…”