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for respiratory disease in 2–3 month-old calves or older animals, but specific vaccines currently are not available for prevention of the respiratory disease (^{Decaro et al., 2008}). Also, some vaccines (i.e., CCoV) have been introduced into the market, used for years and later abandoned, after cost-effectiveness evaluations.⁴ The CCoV vaccines were administered parenterally, induced good systemic but poor mucosal immunity and did not protect pups against infection with virulent virus (^{Pratelli et al., 2003, Pratelli et al., 2004; Decaro et al., 2011}). The only licensed animal CoV vaccines targeted to prevent respiratory CoV infections are IBV vaccines for chickens. These vaccines, administered parenterally, may not protect against the infection but they can reduce the severity of the respiratory signs and prevent involvement of the kidney and reproductive tract (^{Saif, 2020}). One of the main issues of parenteral vaccination against respiratory CoVs in animals is that it does not trigger strong local immunity, usually represented by mucosal immunoglobulin A (IgA). Mucosal immunity, even if not preventing the infection, is able to reduce viral shedding (in terms of duration and extent) and the severity of the respiratory disease. Also this may be the case for SARS-CoV-2, which primarily affects the respiratory tract and, to a lesser extent, the enteric tract, with limited viremia and/or systemic involvement (^{Wong et al., 2020}). Also, the duration of immunity elicited by natural infection with SARS-CoV-2 is not known yet. For animal CoVs, immunity after infection may be of short duration. For instance, feline enteric coronavirus (FECV) may induce short-term immunity that does not confer protection from reinfections. FECV is an avirulent biotype of feline coronavirus (FCoV) and it is the precursor of the hypervirulent biotype FIPV (^{Addie et al., 2020b}). Interestingly, FIP vaccines are paradigmatic of how difficult the development of vaccines against human CoVs may be. FIP is a sporadic but highly lethal disease of cats that originates as a consequence of the switch from FECV to FIPV due to specific mutations in the spike protein gene (^{Chang et al., 2012}). Despite considerable efforts so far, no effective FIPV vaccine has been developed. One of the main issues is that most experimental vaccines triggered an antibody-dependent enhancement (ADE) mechanism, which causes a more severe disease in immunised animals than in control cats after virus challenge (^{German et al., 2004}). ADE is triggered by antibody-mediated virus entry into macrophages via Ig Fc receptors and might represent an obstacle to the development of SARS-CoV-2 specific vaccines (^{Rauch et al., 2018}). An alternative mechanism for ADE has been described recently for MERS-CoV, for which neutralizing antibodies bind to the spike protein, triggering a conformational change of the spike and mediating viral entry into IgG Fc receptor-expressing cells through canonical viral-receptor-dependent pathways (^{Wan et al., 2020}). Analogous to cats affected by FIP, in human patients with severe COVID-19, a cytokine storm syndrome is frequently observed that requires treatment of hyperinflammation to reduce fatality rates. This cytokine storm, which at the same time causes immunosuppression, is characterised by increased interleukin (IL)-2, IL-6, IL-7, granulocyte-colony stimulating factor, interferon-γ inducible protein 10, monocyte chemoattractant protein 1, macrophage inflammatory protein 1-α, and tumour necrosis factor-α (^{Mehta et al., 2020}). Notably, a similar cytokine pattern is observed in cats with FIP (^{Paltrinieri, 2008}). Tocilizumab, an IL-6 receptor blocker monoclonal antibody, seems to be highly effective in reducing the severity of SARS-CoV-2 induced pneumonia (^{Favalli et al., 2020}). A number of antivirals have been tested to control FIP. After several unsuccessful attempts, research efforts have focused on two promising antiviral classes, namely protease inhibitors and nucleoside analogues, which inhibit viral replication either by blocking viral polyprotein cleavage or terminating viral RNA transcription. Treatment of cats with naturally occurring FIP with the 3C-like protease inhibitor GC376 induced a significant remission of disease signs and regression of lesions in 19/20 animals, although only six of these animals remained in remission for a long period (^{Pedersen et al., 2018}). In contrast, long-term and repeated treatment with nucleoside analogue GS-441524 was successful in 25/26 cats with FIP, with only one animal not responding to retreatment (^{Pedersen et al., 2019}). In addition, the same drug was able to stop faecal shedding of FECV in naturally infected cats (^{Addie et al., 2020a}). Interestingly, a similar compound, the adenosine nucleoside monophosphate prodrug GS-5734, is the active molecule of remdesivir, largely employed as a potential antiviral against COVID-19. This drug was shown to be more effective than lopinavir, which, similar to GC376, acts against the viral 3C-like protease (^{Baden and Rubin, 2020}). Considering the long-term experience gained with animal CoVs, veterinary medicine could help to forge a better understanding of the origin and spread of SARS-CoV-2 and drive future research in human medicine towards the development of immunogenic and safe vaccines and effective antiviral drugs. The successes and failures encountered with prophylaxis and treatment of animal CoV diseases, such as FIP, might be useful to address issues related to COVID-19 in a One Health approach. Likewise the atypical pneumonia evident in pigs infected with PRCV, despite mild clinical signs, and the pneumonia in cattle triggered by BCoV in complex with respiratory bacteria and the stress of transport, may provide models to understand factors that precipitate severe pneumonia in COVID-19 patients. Progressive deforestation and anthropization of natural environments have largely compromised some ecological niches where CoVs of wildlife are usually confined. Also, human consumption of endangered wildlife, even if not demonstrated to play a role in the onset of SARS-CoV-2, should be restricted or banned, particularly in the unsanitary conditions prevalent in live animal markets. Considering that animal CoVs spilled over into humans in three different occasions in the short time