Ключевые слова: 19, airport, app, application, businessman, care, certificate, code, corona, coronavirus, covid, covid19, digital, disease, electronic, health, healthcare, illness, immune, immunity, indoors, infection, infectious, international, internet, journey, man, mandatory, medical, medicine, mobile, online, pandemic, passenger, passport, people, person, phone, qr, smart, smartphone, technology, telecommunications, telephone, text, transmission, transmitted, travel, vertical, virus,