1. Environmental Sources of Nontuberculous Mycobacteria
Joseph O. Falkinham, III
Virginia Tech

2. NTM Disease Estimated 30,000 patients in the United States
Increasing prevalence of 5-10 % annually
No cure, recurrence of infection high
Changing pattern of infected:
Pre-1980 older, lung-damaged men (VA Hospitals)
HIV-infected, Mycobacterium avium
2000- Slender, taller, older women and men
Chemotherapy, cancer, immunosuppressed
Cystic Fibrosis
Mycobacterium avium complex dominates

3. NTM as Opportunistic Premise Plumbing Pathogen (OPPP)
Model OPPPs: Mycobacterium avium, Pseudomonas aeruginosa, and Legionella pneumophila
Shared common characteristics lead to survival, persistence, and growth in drinking water systems
Emerging OPPPs:
Acinetobacter baumanii
Aeromonas hydrophila
Methylobacterium spp.
Segnilaparus spp.
Sphingomonas paucimobilis
Stenotrophominas maltophila

4. NTM Players Approximately 150 Mycobacterium species
Mycobacterium avium complex (MAC)
Complex = 4 subspecies & 8 species
Majority of NTM cases in US and Canada
M. avium subsp. hominissuis – water & soil origin
M. intracellulare – soil origin
M. chimaera – described ‘04, water origin
Mycobacterium abscessus – cystic fibrosis
M. abscessus, M. fortuitum, M. chelonae
Hospital-acquired

5. Surrounded by Mycobacteria
Peat-rich Natural and Potting Soils
Natural waters:
Estuaries, Coastal Southeastern U.S. Swamps
Drinking Water:
Showerheads, Sink Taps, and Sink Drains and Traps
Hot Water Heaters (amplifiers)
Humidifiers
Refrigerator Taps and Ice
Medical Equipment:
Catheters, Scopes, Solutions, Ventilators, Heaters/Coolers
Aerosols:
Sinks, Showers, Aerators, Humidifiers

6. Why Surrounded ? Slow-growing Slow-dying Adaptation
Hydrophobic Disinfectant-resistant
Antibiotic-resistant
Biofilm formation
Oligotrophic Grow in drinking water
Microaerobic Stagnation-growth
Heat-resistant Hot water heater
Amoebae-resisting Growth in amoebae

7. Proof
M. avium in shower shares same IS1245 fingerprint as patient isolate
M. avium in household waters same rep-PCR fingerprints as 50 % of isolates from NTM patients
M. avium clone infecting 30 older slender, taller women in Wynnewood, PA with same VNTR as in drinking water
M. intracellulare in potting soil isolates same as patient isolates (rRNA ITS sequence)

8. NTM Questions Why is prevalence of NTM infection increasing?
Demographics?
Physician awareness
Laboratory-diagnosis?
Increase of NTM in environment?
Habitat-driven speciation of M. intracellulare (soil) and M. chimaera (water)
Did the Clean Water Acts lead to M. scrofulaceum disappearance ( )?
Interaction with biofilm microbiome?

9. Methylobacterium and M. avium Do Not Coexist in Biofilms
Mycobacterium spp. Present Absent Total Methylobacterium spp. Present 10 ( 7 %) 32 ( 21 %) 42 ( 27 %) Absent 61 ( 40 %) 50 ( 33 %) 111 ( 73 %) Total 71 ( 46 %) 82 ( 54 %) 153 (100 %)

10. M. avium Adherence Time CFU/cm2 hr Control Normal Methylo 1 Methylo 2
± ± ± ± 1.2
± 5 1,600 ± ± ± 5
± 28 2,050 ± ± ± 1.6
± 33 1,900 ± ± ± 3.2
6 1,100 ± 78 5,600 ± ± ± 8

11. Probiotic Approach
Methylobacterium spp. pink-pigmented, waterborne shower-curtain-loving bacteria
Mycobacteria absent from showerheads with methylobacteria and reverse
Biofilms of methylobacteria reduce adherence of mycobacteria
Methylobacterial viability not required for inhibition of mycobacterial adherence
Methylobacterial inhibition not due to production of extracellular anti-mycobacterial metabolites

12. Remediation Particulate reduction Nutrient reduction
Raise hot water temperature to ≥ 55° C
Clean and disinfection showerheads
Avoid recirculation of hot water
Remove aerators, humidifiers
Point-of-use filters