1. World Health Organization (WHO). Tracking SARS-CoV-2 variants. Geneva: WHO. [Accessed: 30 Dec 2021]. Available from: https://www.who.int/en/activities/tracking-SARS-CoV-2-variants
2. European Centre for Disease Prevention and Control (ECDC). Epidemiological update: Omicron variant of concern (VOC) – data as of 16 December 2021 (12:00). Stockholm: ECDC; 2021. Available from: https://www.ecdc.europa.eu/en/news-events/epidemiological-update-omicron-data-16-december
3. Barnard RC, Davies N, Pearson CAB, Jit M, Edmunds J. Modelling the potential consequences of the Omicron SARS-CoV-2 variant in England | Centre for Mathematical Modelling of Infectious Diseases Repository. London: London School of Hygiene & Tropical Medicine; 2021. Preprint. Available from: https://cmmid.github.io/topics/covid19/omicron-england.html
4. European Centre for Disease Prevention and Control (ECDC). Weekly epidemiological update: Omicron variant of concern (VOC) – week 2 (data as of 20 January 2022) EU/EEA. Stockholm: ECDC; 2022. Available from: https://www.ecdc.europa.eu/en/news-events/weekly-epidemiological-update-omicron-variant-concern-voc-week-2-data-20-january-2022
5. Omicron extensively but incompletely escapes Pfizer BNT162b2 neutralization.;Cele;Nature,2021