Director of Rafik Hariri Hospital Firas Abyad tweeted on Friday the following: "A study published in the prestigious journal, The Lancet, concluded that the first dose of Pfizer's COVID vaccine is up to 85 percent effective on the 15th day after receiving it, in preventing infection that accompanies symptoms, including severe infection, while infections among asymptomatic patients were reduced by 75 percent. Researchers saw that these results support the option adopted by some countries to postpone the second dose of the vaccine due to the early and high effectiveness of the first dose. Therefore if the second dose is postponed, it will allow coverage of a greater number of the most vulnerable people, especially with limited supplies of vaccines in these countries."