Nocardiosis OVERVIEW What Is Nocardiosis? Nocardiosis is a rare infection caused by the Nocardia asteroides bacterium. This type of bacteria can be found in the soil and water of regions around the world. People may become infected with this bacteria when they inhale it or when the bacteria enter an open wound. The infection can’t be spread from one person to another. Nocardiosis most commonly occurs in the lungs, but it may spread to other areas of the body, such as the: *skin *digestive system *brain *kidneys *heart *eyes *bones Though nocardiosis can develop in anyone, the condition is much more likely to affect people with very weak immune systems. An immune system may become compromised as a result of: *cancer *diabetes *lung disease *HIV *AIDS *a bone marrow or organ transplant *the long-term use of steroid medications In the United States, it’s estimated that 500 to 1,000Trusted Source cases of nocardiosis occur each year. In about 60 percent of these cases, the infection i...