Aspergillus spp. is a type of fungus that forms spores. It is normally found in soil, water, and decaying vegetation. In the hospital environment, the spores settle in some part of the ventilation system. Spores are also stirred up from construction and renovation. Additional sources of the fungal spores could be contaminated or wet wood, bird droppings in air ducts, or decaying fireproofing materials. The fungus causes pneumonia in a host with a weak or otherwise compromised immune system. Patients at risk are those undergoing organ tra ....