Empirical evidence shows that NTM infection may occur by exposure to organisms in the environment such as our water or soil.

In a substantial percentage of cases, patients with NTM have some subtle underlying vulnerability that is either genetic or structural in nature. These underlying conditions can include cystic fibrosis, deficiency of a blood protein called alpha-1 antitrypsin, prior lung infection (including TB or histoplasmosis,a fungus common in the Midwest), prior inhalation of inorganic dust including silica, spillage of material from the mouth or stomach into the lungs, or cigarette-induced lung injury.

Other underlying conditions that may increase vulnerability to NTM infection include bronchiectasis, COPD, emphysema and Primary Ciliary Dyskinesia (PCD).

Doctors believe that some patients with these underlying lung conditions may become infected with NTM from inhalation of mycobacteria that become aerosolized when the patient showers in an enclosed shower stall or sits in an indoor hot tub.

For this reason, if you have an underlying condition that might make you susceptible to NTM infection, you may wish to speak to your doctor about the advisability of bathing in a tub rather than showering.