FILE PHOTO: A healthcare worker collects a swab from a

FILE PHOTO: A healthcare worker collects a swab from a passenger for a PCR test against the coronavirus disease (COVID-19) before traveling to Uganda, amidst the spread of the new SARS-CoV-2 variant Omicron, at O.R. Tambo International Airport in Johannesburg, South Africa, November 28, 2021. REUTERS/ Sumaya Hisham/File Photo