1. Analysis of outbreak and global impacts of the COVID-19;Priyadarshini;Healthcare (Basel),2020
2. WHO Declares COVID-19 a Pandemic;Cucinotta;Acta Biomed,2020
3. World Health Organization (WHO). Coronavirus disease (COVID-19) pandemic. [cited 4 March 2021]. Available from: https://www.who.int/emergencies/diseases/novel-coronavirus-2019?gclid=Cj0KCQiA6Or_BRC_ARIsAPzuer_EFDouGeVvsxjB6pinzNQNyd6kLUjTkw7gAuA9ak-1cbBRtY-bCqwaAh6IEALw_wcB
4. COVID-19 strategy up date;World Heal Organ,2020
5. CDC COVID-19 Response Team. Severe Outcomes Among Patients with Coronavirus Disease 2019 (COVID-19) - United States, February 12-March 16, 2020. MMWR Morb Mortal Wkly Rep. 2020;69(12):343-346. Published 2020 Mar 27. 10.15585/mmwr.mm6912e2