NELSON Mandela is comfortable and breathing without difficulty on his third day in hospital after the anti-apartheid hero was treated for pneumonia, South Africa's presidency says. Messages of concern for the ailing 94-year-old, one of the towering figures of modern history, have poured in since his admission late Wednesday for what was confirmed as "a recurrence of pneumonia." Mandela had a build-up of fluid that had developed from a lung infection, known as a pleural effusion or "water on the lungs," drained from his chest. "This has resulted in him now being able to breathe without difficulty," said President Jacob Zuma's office said in a statement on Saturday. He continues to respond to treatment and is comfortable. On Friday, Mandela was said to be in good spirits and making steady progress. "He sat up and had his breakfast in bed," Zuma's spokesman Mac Maharaj, who was jailed with Mandela during apartheid, told AFP. There were no details on Saturday on how long he would remain at an undisclosed hospital. The former president is idolised in his home nation, where he is seen as the architect of South Africa's peaceful transition from white minority-ruled police state to hope-filled democracy. Nearly 20 years after he came to power in 1994, the first black president remains a unifying symbol in a country still riven by racial tensions and deep inequality. It is the second time this month that Mandela has been admitted to hospital, after spending a night for check-ups on March 9. That followed a nearly three-week hospital stay in December, when he was treated for another lung infection and underwent gallstone surgery. Keertan Dheda, professor of respiratory diseases at the University of Cape Town medical department, said a pleural effusion was the accumulation of water between the lining covering the lung and that of the chest wall. Having the fluid tapped was a minor procedure, he said. "One can drain the fluid with a needle and a catheter and in some cases that's all that's needed," he said. Other cases required the fluid to be chemically broken down if it had formed pockets or a small operation if infected. "The older you are, the longer pneumonia takes to get better," said Dheda, adding that mortality was also higher. It takes a bit longer, everything is a bit slower and a bit more complicated the older you get. While Mandela's legacy continues to loom large over South African politics, he has long since exited the political stage and for the large young population he is a figure from another era, serving as president for just one term. He has not appeared in public since South Africa's football World Cup final in 2010. Labour unrest, high-profile crimes, grinding poverty and corruption scandals have effectively ended the honeymoon enjoyed after Mandela ushered in the "Rainbow Nation," but his decades-long struggle against apartheid still resonates. The whole country is not happy about the old man's health. He is not so well, but we wish him a speedy recovery," Soweto handicraft seller Nhlanhla Ngobese told AFP on Saturday. We want him back, even though he's an old man, he's an icon to us, a hero to us, we still want his diplomacy.