1. World Health Organization. Coronavirus disease (COVID-2019) situation reports. Available from: https://www.who.int/emergencies/diseases/novel-coronavirus-2019/situation-reports. Accessed May 30, 2020.
2. Current perspective on pandemic of COVID-19 in the United States
3. EMERGING INFECTIOUS DISEASES AND TRAVEL MEDICINE
4. Zimmer C. Most New York coronavirus cases came from Europe, genomes show. The New York Times. Available from: https://www.nytimes.com/2020/04/08/science/new-york-coronavirus-cases-europe-genomes.html. Accessed June 25, 2020.
5. The traveller and emerging infections: sentinel, courier, transmitter