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Coronaviruses (CoVs) are enveloped, single-stranded, positive-sense RNA viruses displaying an exceptional genetic plasticity driven by accumulation of point mutations and recombination events. This genetic variation is responsible for continuous emergence of viral strains with increased virulence, different tissue tropism and/or expanded host range (^{Buonavoglia et al., 2006}). CoVs are currently classified within four genera, Alphacoronavirus, Betacoronavirus, Gammacoronavirus and Deltacoronavirus, that recognise bats, birds and likely rodents as natural reservoirs. In December 2019, cases of undiagnosed pneumonia started being reported in Wuhan, Hubei, China. On January 9 2020, the Chinese authorities indicated that a novel CoV was associated with the severe respiratory disease. The first patient with unexplained pneumonia, identified in December 8 2019, came from Wuhan South China Seafood Market. Initially, other patients were linked to the same seafood and live animal market, suggesting an animal origin for the initial spread to humans. Subsequent investigations revealed that the crowded seafood market only boosted circulation of the novel CoV and spread it to the whole city in early December 2019, whereas based on the genome data the virus likely began spreading from person to person in early December or even as early as late November. The first documented human case has been dated back to November 17 2019. The novel human CoV (HCoV) is a betacoronavirus genetically related to Severe acute respiratory syndrome (SARS) CoV and only distantly related to Middle East respiratory syndrome CoV (MERS-CoV) and it was designated as SARS type 2 CoV (SARS-CoV-2). Similar to the other hypervirulent HCoVs, SARS-CoV-2 has a putative animal origin, likely descended from a related bat CoV that spilled over to humans either directly or after adaptation in another animal species, such as the Malayan pangolin (^{Lam et al., 2020}). SARS-CoV-2 is highly related genetically (96% nt) to a SARS-like bat CoV (^{Zhou et al., 2020}) The SARS-CoV-2 induced disease, referred to as CoronaVirus Disease 2019 (COVID-19), affects the respiratory tract, with a number of patients displaying severe pneumonia and requiring hospitalisation and admission to intermediate or intensive care units. Unlike SARS and MERS, COVID-19 is characterised by low lethality rates and high frequency of asymptomatic or paucisymptomatic infections that likely favoured the spread of this new pandemic (^{Lai et al., 2020}). As SARS-CoV-2 started spreading globally, between February and March 2020, potential spill over exposure (viral RNA) was noted in companion animals, likely due to their strict social interactions with humans. SARS-CoV-2 RNA was detected in two dogs and a cat without clinical signs in Hong Kong and in a cat with gastroenteric and respiratory signs in Bruxelles, all which lived in close contact with infected COVID-19 human patients.^{1 , 2} This noted analogous findings observed during the 2002–2003 spread of SARS-CoV.³ 2. Animal coronaviruses: the experience of veterinary medicine Before the emergence of SARS-CoV, the first highly pathogenic HCoV, information was very scarce about HCoVs, whereas there was extensive knowledge in veterinary medicine about animal CoVs, their evolution and pathobiology. Infectious bronchitis virus (IBV) of poultry and feline infectious peritonitis virus (FIPV) have been known since the early 1900, representing animal examples on how CoVs can evolve, changing their tissue tropism and virulence (^{Decaro and Lorusso, in press}). In addition, swine CoVs are paradigmatic on how CoVs may cross the species barriers infecting new hosts. Transmissible gastroenteritis virus of swine (TGEV, alphacoronavirus), likely originated from the closely related canine coronavirus (CCoV) (^{Lorusso et al., 2008}) and in turn TGEV gave rise to the less virulent porcine respiratory CoV (PRCoV). Also, a TGEV-like CCoV was generated by recombination in the N terminal end of the S gene (^{Decaro et al., 2009}). Two additional swine alphacoronaviruses emerged more recently, the porcine epidemic diarrhoea virus (PEDV) and the severe acute diarrhoea syndrome CoV (SADS-CoV), both derived from CoVs circulating in bats. The betacoronavirus porcine haemagglutinating encephalomyelitis virus (PHEV) was a derivative of bovine CoV, which in turn is believed to have descended from a bat virus through adaptation in a rodent species. More recently, porcine deltacoronavirus (PDCoV), the causative agent of severe diarrhoea outbreaks in North America and Asia, emerged from avian deltacoroviruses (^{Wang et al., 2019}). The observed repeated events of inter-species transmission by animal CoVs rely on the exceptional ability of CoVs to expand their host range. This strongly supports the natural origin of SARS-CoV-2, confuting conspiracy theories of a laboratory origin (^{Liu et al., 2020}). Animal CoVs may also represent excellent host models for development of SARS-CoV-2 vaccines, which could require much more time than initially anticipated. The majority of vaccines licensed for the veterinary market have been developed for CoVs causing enteric infections, such as BCoV and the swine CoVs TGEV and PEDV. These vaccines are intended for parenteral use in pregnant cows/sows or oral use in sows (TGEV, PEDV) to transfer maternal immunity to their offspring and protect them in the first weeks of life, when they are more susceptible to severe of disease. These vaccines take advantage of different technologies, since BCoV/TGEV vaccines are inactivated or modified-live virus (MLV) formulations that are produced according to traditional protocols. For PEDV prophylaxis, in addition to killed and MLV preparations, vector-based vaccines expressing the spike protein are commercially available (^{Gerdts and Zakhartchouk, 2017; Saif, 2020}). BCoV is also responsible