Ключевые слова: analysis, arm, assay, background, blood, care, closeup, covid19, crown, doctor, enzyme linked immunosorbent assay, epidemic, equipment, global, hand, health, holding company, hospital, human, illness, immunity, immunological memory, infection, kit, laboratory, liquid, male, man, medic, medical, medicine, nasal, oral, pandemic, person, polymerase chain reaction, quarantine, reinfection, sarscov2, second wave, serological, serum, sharp, sputum, test, tube, virus, white,