COVID-19 Vaccines/immunology; COVID-19/immunology; COVID-19/prevention & control; Immunization Programs; Internationality; Research Personnel; SARS-CoV-2/immunology; Vaccinology; Adolescent; Aged; Aged, 80 and over; Aging/immunology; COVID-19/mortality; COVID-19/virology; COVID-19 Vaccines/administration & dosage; COVID-19 Vaccines/adverse effects; COVID-19 Vaccines/supply & distribution; Carrier State/immunology; Carrier State/prevention & control; Child; Disease Transmission, Infectious/prevention & control; Female; Healthcare Disparities/statistics & numerical data; Humans; Immunity, Herd/immunology; Immunization, Secondary; Middle Aged; Patient Safety; Qatar/epidemiology; Reinfection/immunology; Reinfection/prevention & control; Reinfection/virology; Research Personnel/education; Seychelles/epidemiology; South Africa/epidemiology; Time Factors; United Kingdom/epidemiology; United States/epidemiology; Vaccinology/education; Vaccinology/trends; Viral Load; Virus Shedding/immunology; World Health Organization/organization & administration

Epidemiology; Infection; SARS-CoV-2; Vaccines