Although the incubation period of Pneumocystis pneumonia is not definitely known, it is believed to be between four and eight weeks.
The major symptoms of the disease are fever, a non productive cough and shortness of breath. Lesser known symptoms include production of sputum, blood in sputum, chest pain and difficulty breathing.
Most patients experience symptoms for a week or two before they consult the physician. The disease occasionally spreads outside of the lungs and infects other organs like the spleen, lymph nodes, bone marrow or liver.