omicron, 2019-ncov, 3d omicron, africa, ban, biology, cell, classification, coronavirus, covid-19, covid-19 variant, dangerous, disease, doctor, epidemic, evolution, graphic, health, health care, humans, illness, india, infection, limit, lock down, microscopic, mutation, new, new cases, omicron variant, one person, organism, outbreak, pandemic, red, reinfection, research, restrict, south, south africa, vaccine, variant, vial, virology, virus, virus background, who, world health organization