1. WHO Regional Office for Africa. First case of covid-19 confirmed in ethiopia. WHO. Regional Office for Africa [Internet]. World Health Organization. 2020. Available from: https://www.afro.who.int/news/first-case-covid-19-confirmed-ethiopia.

2. Hauck G, Gelles K, Bravo V, Mitchell Thorson UT Five months in: A timeline of how COVID-19 has unfolded in the US [Internet].New England Journal of Medicine. 2020. Available from: https://www.usatoday.com/in-depth/news/nation/2020/04/21/coronavirus-updates-how-covid-19-unfolded-u-s-timeline/2990956001/?utm_source=feedblitz&utm_medium=FeedBlitzRss&utm_campaign=usatoday-newstopstories.

3. Multnomah County Health Department. COVID19 Cleaning & Sanitizing Guidelines for Restaurants & Food Service [Internet]; 2020. Available from: https://multco.us/covid-19-cleaning-and-sanitizing-guidelines-restaurants-food-service.

4. World Health Organization. Operational considerations for COVID-19 management in the accommodation sector [Internet]; 2020. Available from: https://www.euro.who.int/en/health-topics/health-emergencies/coronavirus-covid-19/technical-guidance/2020/operational-considerations-for-covid-19-management-in-the-accommodation-sector-interim-guidance,-31-march–2020.

5. Public Health Ontario. COVID-19 – what We Know So Far A bout Asymptomatic Infection and Asymptomatic Transmission. Toronto, ON: Queen’s Printer for Ontario; 2020.