Introduction to SARS-COV 2

• Coronavirus are unsegmented single-stranded positive-strand RNA viruses.
• They belong to the order Nidovirales, the family Coronaviridae, and the subfamily Ortho Coronaviridae, which is divided into α (alpha or one), β (beta or two), γ (gamma or three), and δ (delta or four) genera according to their serotype and genomic characteristics.
• Coronaviruses belong to the genus Coronavirus of the family Coronaviridae.
• Coronaviruses have an envelope encasing the RNA genome.
• The virions (the whole viruses) are round or oval, often polymorphic, with a diameter of 50 to 200 nm.
• The novel coronavirus is 60 to 140 nm in diameter.
• The spike protein is located on the surface of the virus and forms a rod-like structure.
• As one of the main antigenic proteins of the virus, the spike protein is the main structure used for typing.  
• The nucleocapsid protein encapsulates the viral genome and can be used as a diagnostic antigen.