Pope John Paul's fragile health has stabilised today after urgent medical treatment overnight for severe breathing difficulties, but he will have to remain in hospital for the time being, the Vatican said.
Chief spokesman Mr Joaquin Navarro-Valls said the 84-year-old Pope, who was rushed to Rome's Gemelli hospital last night, had needed help with his breathing and was running a slight fever today.
He added that the Pontiff would remain hospitalised "for a few more days", but stressed that he had never lost conciousness during the latest in a long line of health scares.
"I think everyone has to be calm because there is no reason for alarm today," said Mr Navarro-Valls, himself a doctor. The Vatican issued its first full health bulletin as Catholics around the world - from the Pope's native Poland to Manhattan to the Philippines - attended special church services to pray for his recovery.
Italian health minister, Mr Girolamo Sirchia visited the Gemelli hospital later in the day and said the Pope was recovering. "He is improving, the doctors are optimistic," Mr Sirchia told reporters as he left the institute on the outskirts of Rome.
The sudden illness of a Pontiff once known as "God's Athlete" because of his fitness raised speculation that one of the longest, most remarkable and most controversial papacies in history might be fading.
The Pope, who also suffers from debilitating Parkinson's disease, came down with influenza on Sunday, forcing him to cancel all public engagements at the start of the week.
Vatican spokesman, Mr Joaquin Navarro-Valls
His condition deteriorated rapidly yesterday with an acute attack of laryngospasm, a blockage of air to the lungs.
Medical experts said the ailment was very rarely fatal, but cautioned that the Pope's age and frailty complicated matters.
Mr Navarro-Valls said that during the night the Pope had received "respiratory assistance therapy" that had "stabilised his clinical framework". He did not elaborate.
The Pope had rested "for several hours" and was able to participate in a mass from his hospital bed that was celebrated by his long-time Polish secretary.
While the Pope is in hospital, ordinary Vatican business will be taken care of by his top aides, such as the Secretary of State. But they have no power to alter Church teachings on issues of faith and morals.
As news of his illness spread, the world's media and well-wishers set up camp outside the Gemelli, the hospital where the Pope has received treatment on at least six occasions during his 26-year papacy, including when he was shot in an assassination attempt in 1981.