Catholic spiritual leader and his predecessor Pope Benedict have received their first vaccination against COVID-19, the Vatican said on Thursday.
Francis, who is 84, had part of a lung removed due to an illness in his 20s, so he would be a high-risk patient if he were to contract the virus, the Nation reports.
The Vatican began its vaccine roll-out on Wednesday.
It said health-care workers, security personnel and the elderly would be first in line, as well as personnel who have frequent contact with the public.
In recent months, there have been several Coronavirus outbreaks in the Vatican, including among members of the Swiss Guard.