Methylobacterium spp. as an indicator for the presence or absence of Mycobacterium spp.

Objective/BackgroundA published survey of bacteria in showerhead biofilm samples revealed that Methylobacterium spp. and Mycobacterium spp. seldom coexisted in biofilms.MethodsTo confirm that information, biofilm samples were collected from household plumbing of Mycobacterium avium patients and Methylobacterium spp. and M. avium numbers were measured by direct colony counts.ResultsThe results demonstrated that if Methylobacterium spp. were present, Mycobacterium spp. were absent, and the opposite.ConclusionThe data demonstrate that microbial populations in biofilms can influence the presence or absence of opportunistic premise plumbing pathogens and, thereby, increase the range of strategies to reduce exposure to waterborne pathogens. Finally, by assessing for the visual presence of methylobacteria as pink pigmentation on showers and shower curtains, homeowners and managers of hospitals and other buildings can quickly determine whether a premise plumbing biofilm sample has mycobacteria with a high degree of assurance.