A Vatican source said its first coronavirus patient had participated in an international conference hosted by the Pontifical Academy of Life last week in a packed theatre several blocks from the Vatican.
Participants at the three-day conference on Artificial Intelligence included top executives of U.S. tech giants Microsoft and IBM.
The academy issued a separate statement saying it was informing all other participants of the development by email but did not say it was the same person whose case was announced earlier by Vatican spokesman Matteo Bruni.
The discovery worsened the prospects of the virus having already spread further in the capital of Italy, since most Vatican employees live in Rome and those who live in the Vatican frequently enter and leave the city state.
The death toll in Italy, the worst-hit European country, stood at 197 on Friday. The north of the country has been the most heavily hit.
Bruni said the case was diagnosed on Thursday and that services in its clinics had been suspended to sanitize the areas.
Most Vatican employees who use its health services live in Italy on the other side of the border with the 108-acre city state.
Bruni gave no details on whether the person who tested positive was such an employee or among the relatively few clergy or guards who live inside its walls.
Italian health authorities said that, as of Friday, 49 people had tested positive for coronavirus in Rome province.
Pope Francis cancels appearances and Lent retreat
Pope Francis has cancelled his regular appearances in public to avoid crowds gathering to see him and will stream them on the internet from inside the Vatican because of the coronavirus outbreak in Italy.
The Vatican said that on Sunday the pontiff will not address crowds from a window overlooking St. Peter’s Square, and will also not hold his general audience from there this Wednesday.
Both will be held without general public participation from inside the official papal library in the Vatican’s Apostolic Palace and will be viewable on the internet or television, the Vatican said in a statement on Saturday.
The participation of the faithful at the pope’s morning Mass in his residence has been suspended until March 15.
Pope Francis cancelled a Lent retreat for the first time in his papacy, but the Vatican has said he is suffering only from a cold that is “without symptoms related to other pathologies”.
Reporting by Philip Pullella