Pope Francis met on Wednesday (April 16) at the Vatican with members of the medical team who saved his life during a five-week hospital stay for a serious case of double pneumonia, thanking them for their care.

The 88-year-old pontiff is gradually making more public appearances as he recovers from the most severe health crisis of his 12-year papacy.

During the audience, he met with about 70 doctors and staffers at Rome's Gemelli hospital, where he was treated for 38 days.

"Thank you for all that you have done," Francis said, speaking in a soft, raspy voice.

As during his last public appearance on Sunday (April 13), the pope did not receive oxygen during the meeting but breathed on his own.

"Thank you for your service in the hospital," the pope said. "It is very good. Keep going like this."

The pope's medical team have urged him to take two months' rest after leaving hospital to allow his ageing body to fully heal. Francis initially remained out of view after returning home but has now made several brief public appearances.

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The Vatican on Thursday (April 17) will start its busiest holiday season, with at least six religious celebrations in the four days leading to Easter, the most important Christian holiday, on Sunday (April 20).

It is still not known how much the pope will participate in the events. The Vatican has delegated senior cardinals to lead each of the celebrations in the pope's place.

(Production: Cristiano Corvino, Fabiano Franchitti)