The first phase From 9 December 2020 to 31 March 2021 Health care personnel most at risk of infection (workers in facilities designated for COVID-19 patients, intensive care units, etc) Key personnel and first responders (ambulance teams, Ministry of Interior, Ministry of Defense, oil and gas sector, Hamad International Airport and Qatar Airways) Long-term care and home care patients and people who are aged 70 and up Adults with severe or multiple conditions are most at risk of developing COVID-19 All people aged between 50 to 69 More health care cadres and essential workers and 50% of teachers. The second phase From April 1 to June 30, 2021 All health care personnel not included in the first stage. The essential workers in the ministries and industries necessary for the continuation of work in society and are most at risk of exposure to or transmitting the disease.