LAUSR

Background By the end of 2021, the SARS-CoV-2 Variant of Concern (VOC) Delta was predominant in most of the world. At the end of November, the Omicron variant was first detected in South Africa. This variant was immediately classified as VOC, due to the explosive increase of cases in South Africa, and the great number of mutations exhibited by this new lineage. Since then, Omicron VOC displaced Delta one in almost every country. Venezuela implemented in May 2021 molecular testing of all the passengers arriving at Venezuelan airports. Methods In this study, we analyzed the presence of variants of SARS-CoV-2 in those positive samples, by sequencing a small fragment of the Spike genomic region. Results The Omicron variant was found in passengers arriving to Venezuela from the beginning of December. Complete genome analysis confirmed the presence of the Omicron VOC. The detection of this VOC coincided with an unprecedented increase in the frequency of passengers with positive nucleic acid testing. Conclusions Genomic surveillance of samples for international travelers returning to Venezuela allowed us to rapidly detect the introduction of the Omicron variant in the country.