The World Health Organization has stated that people should get two doses of the Pfizer and BioNTech COVID-19 vaccine within 21-28 days, as many countries struggled to administer the shots.

Several countries are facing increasing pressure on their health services owing to rising coronavirus cases and the emergence of new variants. Amid limited supply of the vaccine doses, the WHO has been evaluating how they can be used most effectively, and came out with the recommendation that two doses of this (Pfizer) vaccine should be given within 21-28 days. A WHO panel said that countries should have the scope to spread out the vaccine shots over six weeks so that more people at higher risk of illness can receive the vaccine. WHO’s Strategic Advisory Group of Experts on Immunization (SAGE) has introduced a provision for countries in exceptional circumstances of (Pfizer) vaccine supply constraints to delay the second dose for a few weeks to augment the number of individuals that can benefit from a first dose…(Reuters, January 5, 2021)