1. World Health Organization. Coronavirus disease (COVID-2019) situation reports. 2020. https://www.who.int/emergencies/diseases/novel-coronavirus-2019/situation-reports (accessed Dec 2020).
2. World Health Organization. Global surveillance for COVID-19 caused by human infection with COVID-19 virus: interim guidance. 2020. https://www.who.int/publications-detail/global-surveillance-for-covid-19-caused-by-human-infection-with-covid-19-virus-interim-guidance (accessed 18 May 2020).
3. World Health Organization. WHO COVID-19 Case definition. 2020. https://www.who.int/publications/i/item/WHO-2019-nCoV-Surveillance_Case_Definition-2020.1. (accessed Dec 2020).
4. UK Government. Number of coronavirus (COVID-19) cases and risk in the UK. Number of coronavirus (COVID-19) cases and risk in the UK. 2020. https://www.gov.uk/guidance/coronavirus-covid-19-information-for-the-public (accessed 27 Apr 2020).
5. Ai T, Yang Z, Hou H, et al. Correlation of Chest CT and RT-PCR Testing in Coronavirus Disease 2019 (COVID-19) in China: A Report of 1014 Cases. Radiology 2020;:200642. https://doi.org/10.1148/radiol.2020200642.