INTRODUCTION

peplomers, surrounding a core structure with a helical nucleocapsid. These peplomers confer the viruses with a crown-like appearance, and the name ‘coronavirus’ was derived from corona in Latin, meaning ‘crown’.

The Coronaviridae contain numerous pathogens of a wide range of mammals and birds and cause a variety of diseases, although many infections are subclinical. In animals, coronaviruses generally cause respiratory or intes­tinal infections, but they have also been associated with a wide spectrum of other clinical symptoms, including hepatic, renal, reproductive and neurological dysfunctions. The remarkable diversity of coronaviruses results from their large genome together with their high mutation and recombination abilities. This causes emergence of new virus species and adaptation to new hosts and ecological niches, sometimes causing major zoonotic outbreaks®.