This 'crown-like' appearance gives the family its name. Centre of particle appears amorphous in -ve stained EM preps, the nucleocapsid being in a loosely wound rather disordered state. The genome is associated with a basic phosphoprotein, N . To view a negatively-stained electron micrograph of a coronavirus particle, click here . 6-8h for influenza.
Replication occurs in the cytoplasm .
The exact number of human isolates are not known as many cannot be grown in culture. Greatest incidence in children in winter, less common in adults.