Pope Francis is sick and skipped a planned Mass with Rome clergy across town on Thursday, officials said.

The Vatican said the 83-year-old pontiff had a “slight indisposition" and would proceed with the rest of his planned work on Thursday. But Francis “preferred to stay near Santa Marta," the Vatican hotel where he lives.

There was no word from the Vatican about the nature of his illness, but the pope was seen coughing and blowing his nose during the Ash Wednesday Mass. It comes amid an outbreak of the coronavirus in Italy that has sickened more than 400 people, almost all of them in the north. Rome had three cases, but all three were cured.

Francis had been scheduled to go to the St. John Lateran basilica across town to meet with Rome clergy and celebrate a penitential Mass at the start of Lent. Francis is bishop of Rome, but delegates the day-to-day running of the archdiocese to a vicar.

The Argentine pope has generally enjoyed good health. He lost part of one lung as a young man because of a respiratory illness, and suffers from sciatica, which makes walking difficult.

Francis has had a busy schedule lately, including his public general audience on Wednesday and the Ash Wednesday service later in the day in a Roman basilica, where he spoke about the coronavirus, saying , "I wish, again, to express my closeness to those who are ill with coronavirus and to health-care workers who are caring for them."

During the audience, Francis made a point to shake hands with the faithful in the front row, kissed a baby during his popemobile spin through St. Peter's Square and greeted visiting bishops at the end. The prelates, however, appeared to be refraining from kissing his ring or embracing him, as they normally would do.