Mendella's Medical Update: Illness Caused by Pneumonia is encouraging news after that health scare for nelson mandela. The icon now spending a fourth night in the hospital there rushed because of pneumonia. This evening we're learning more about his condition. Abc's ron claiborne is in south africa tonight, ron. Reporter: David, nelson mandela we believe is being treated at a private clinic in pretoria and tonight signs that his precarious health is improving. At first the south african government said that mandela was suffering from a lung infection, oday saying he actually had fluid around his lungs, a common symptom of pneumonia. Officials say the fluid has been cleared, which has, quote, resulted in him now being able to breathe without difficulty. This is the third time since december that mandela has been hospalized for lung problems, which could be related to the tuberculosis he contracted during his 27 years in prison. Of course, there is concern whenever nelson mandela is hospitalized but the government is saying he is comfortable and is responding,