Colour enhanced negative-stained transmission electron micrograph (TEM) revealing the presence of numerous coronavirus virions (many highlighted in blue) in this tissue sample. Coronavirus is a member of the virus family,Coronaviridae,which at their core contain a positive-sense single-stranded RNA genome ((+) ssRNA). Under electronmicrographic examination,the envelope surrounding each virion is studded with a corona of points,hence the derivation of its name,which are actually proteinaceous in nature,and are outcroppings of its envelope's molecular structure. Coronaviruses infect mammals and birds with upper respiratory and gastrointestinal illnesses. The most well-known member of this virus family is the human coronavirus responsible for causing severe acute respiratory syndrome (SARS). The SARS corona virus,or SARS-CoV,was first reported in Asia in February 2003. Over the next few months,the illness spread to more than two dozen |