The Rising Cousins: Non-tuberculous Mycobacteria (NTM)

The incidence and number of deaths from NTM disease have been steadily increasing globally. These lesser-studied "cousins" of Mtb were once thought to be harmless habitants. However, it is now clear that NTM infections are commonly affecting seemingly immune-competent individuals at increasing rates through pulmonary infection. While several competing scenarios have been proposed as causes for the rise of NTMs, the reasons behind this NTM increase are only beginning to be elucidated.

NTM infections are extremely difficult to treat. For instance, the cure rates for M. abscessus infection are below 50% even after using a combination of 4-5 drugs for many months. The fact that NTMs are resistant to most available antibiotics has left us with very few treatment options for these infections. Additionally, it is evident that NTMs are developing acquired resistance during treatment. While the current understanding suggests that patients acquire NTM infections from the environment independently, the rapid international dispersal of NTMs suggests transmission through person-to-person contact.

In this lab, we are interested in addressing the following questions: What are the ecological driving factors underlying the recent rapid expansion of NTMs? How much heterogeneity exists in the pathogenicity of different strains, and what are the genetic determinants? Why are NTMs intrinsically resistant to so many different antibiotics, and can we reverse their resistance? How do NTMs evolve de novo drug resistance, and what role does horizontal gene transfer play in this evolution? Finally, what bacterial factors are associated with treatment failure in NTM patients?