JOHANNESBURG -- After a second night in a hospital being treated for a recurrent lung infection, former President Nelson Mandela of South Africa was in good spirits on Friday, enjoying breakfast and making steady progress, according to the office of President Jacob Zuma, who had earlier urged his compatriots not to panic.
But the statement from Mr. Zuma gave no clue about when Mr. Mandela, 94, might be discharged. He was admitted to the hospital late Wednesday night for the third time in four months. The authorities delayed an initial announcement for several hours, and the episode has rekindled worries about his frailty.
In its latest statement on Friday Mr. Zuma's office said: "The presidency wishes to advise that former President Nelson Mandela is in good spirits and enjoyed a full breakfast this morning, 29 March 2013. The doctors report that he is making steady progress. He remains under treatment and observation in hospital."
The brief bulletin, which did not explain the details of Mr. Mandela's condition, came hours after Mr. Zuma seemed to be seeking to steady South African public opinion, urging his compatriots to "slow down the anxiety" but counseling them to think about the former president's advancing years.
"Of course I have been saying to people, you should bear in mind Madiba is no longer that young and if he goes for checkups every now and again, I don't think people must be alarmed about it," Mr. Zuma told the BBC, referring to Mr. Mandela by his clan name. "I would like to really say the country must not panic."
Asked in the interview if people should prepare for "the inevitable," Mr. Zuma said: "In Zulu, when someone passes away who is very old, people say he or she has gone home. I think those are some of the things we should be thinking about."
But, he said, "We would want Madiba to be with us for a long time."
As South Africa's first black president and a former leader of the dominant African National Congress, who spent 27 years in prison for his beliefs, Mr. Mandela is seen as a living embodiment of the long struggle against apartheid.
His incarceration became a potent symbol in South Africa and around the world of the struggle to throw off a system of racial domination devised by the country's white rulers. But the prison years took a toll on his health when he contracted tuberculosis, foreshadowing a long battle with pulmonary problems.
Mr. Mandela spent 19 days in December hospitalized for a lung infection and what government officials described as the surgical removal of gallstones. He returned earlier this month for what was termed a scheduled checkup.
"We appeal to the people of South Africa and the world to pray for our beloved Madiba and his family and to keep them in their thoughts," Mr. Zuma's initial statement said on Thursday. "We have full confidence in the medical team and know that they will do everything possible to ensure recovery."
Later on Thursday, the president's office issued another statement saying that Mr. Mandela's doctors said he was "responding positively to the treatment he is undergoing."
Mr. Mandela led the A.N.C. through the negotiations that led to the first fully democratic elections in 1994 and the end of white minority rule. His name still resonates as an emblem of his effort to transcend decades of racial division and create what South Africans called a rainbow nation.
Mr. Mandela retired from public life in 2004 and was last seen publicly in 2010, when he briefly appeared at the World Cup soccer tournament, which South Africa hosted. But he receives frequent visits from old friends. When Mr. Mandela was discharged from the hospital in December, Mac Maharaj, a spokesman for Mr. Zuma, said Mr. Mandela would be staying at home in a suburb of Johannesburg and receiving high-level care there.
His recurrent bouts of illness have added to a sense of foreboding after a year in which South Africa has faced perhaps the most serious unease and unrest since the end of apartheid. It has been provoked by a leadership struggle within the A.N.C. and a wave of strikes by mine workers.
Additionally, Mr. Zuma has come under public scrutiny in recent months, particularly in relation to how $27 million of government money has been spent on upgrades to a private homestead and compound in Zululand. The questions highlight a broader perception that Mr. Mandela's near saintly legacy from the years of struggle has been eroded by a scramble for self-enrichment among a newer elite.
Lydia Polgreen reported from Johannesburg and Alan Cowell from London.
This article originally appeared in The New York Times.