Fatal Nontuberculosis Mycobacteria Are Not Contagious, But Still Infectious

Rare yet fatal lung infection-causing bacteria come from the same family as tuberculosis, but are not contagious.

Caucasian patients aged 55 or older have the greatest risk for nontuberculous mycobacteria (NTM) infection, according to a study published in PLOS ONE.

Researchers from the University of Illinois at Chicago College of Medicine say the bacteria, which are in the same family as the bacteria that cause tuberculosis and are found in water and soil, can infect the lungs when inhaled, but are not contagious or spread from person to person. While infection from the bacteria is treatable, it can take up to 2 years.

Although the condition is rare, the investigators desired to identify which patients are at the highest risk for becoming infected. Between 1999 and 2010, NTM was listed as the cause of death for 2,990 people. Nearly all (87%) were 55 or older, 85% were white, and 52% were female. Residents of Hawaii were 9 times more likely to die from NTM than residents of Michigan, where the lowest mortality rate was found. Other states with high NTM mortality rates included Louisiana, Arizona, South Carolina, North Carolina, and Florida, but thus far, researchers have been unable to pinpoint a cause for the variation.

The study authors noted the strongest correlation for NTM deaths was older age; however, smoking status, cancer, HIV infection, and chronic obstructive pulmonary disease (COPD) were also significant factors.

“People and physicians need to be aware of NTM, especially as we see more of it, and because it can look like a lot of other pulmonary diseases,” lead study author Mehdi Mirsaeidi, MD, MPH, said in a statement. He noted NTM patients usually present with a cough, and it can take years to make a correct diagnosis.