Opportunistic pathogens enriched in showerhead biofilms

The environments we humans encounter daily are sources of exposure to diverse microbial communities, some of potential concern to human health. In this study, we used culture-independent technology to investigate the microbial composition of biofilms inside showerheads as ecological assemblages in the human indoor environment. Showers are an important interface for human interaction with microbes through inhalation of aerosols, and showerhead waters have been implicated in disease. Although opportunistic pathogens commonly are cultured from shower facilities, there is little knowledge of either their prevalence or the nature of other microorganisms that may be delivered during shower usage. To determine the composition of showerhead biofilms and waters, we analyzed rRNA gene sequences from 45 showerhead sites around the United States. We find that variable and complex, but specific, microbial assemblages occur inside showerheads. Particularly striking was the finding that sequences representative of non-tuberculous mycobacteria (NTM) and other opportunistic human pathogens are enriched to high levels in many showerhead biofilms, >100-fold above background water contents. We conclude that showerheads may present a significant potential exposure to aerosolized microbes, including documented opportunistic pathogens. The health risk associated with showerhead microbiota needs investigation in persons with compromised immune or pulmonary systems.

[1]  D. Kamp,et al.  Infectivity of Legionella pneumophila mip mutant for alveolar epithelial cells , 1995, Current Microbiology.

[2]  N. Pace,et al.  Molecular-phylogenetic characterization of microbial community imbalances in human inflammatory bowel diseases , 2007, Proceedings of the National Academy of Sciences.

[3]  R. Donlan,et al.  Structural Analysis of Biofilm Formation by Rapidly and Slowly Growing Nontuberculous Mycobacteria , 2008, Applied and Environmental Microbiology.

[4]  D. van Soolingen,et al.  Mycobacterium avium in a shower linked to pulmonary disease , 2008 .

[5]  D. G. Boyer,et al.  Aquifer-protection considerations of coalbed methane development in the San Juan Basin , 1993 .

[6]  J. Hacker,et al.  The PPIase Active Site of Legionella pneumophila Mip Protein Is Involved in the Infection of Eukaryotic Host Cells , 2003, Biological chemistry.

[7]  J. Thorn The inflammatory response in humans after inhalation of bacterial endotoxin: a review , 2001, Inflammation Research.

[8]  K. Schleifer,et al.  Microbiological safety of drinking water. , 2000, Annual review of microbiology.

[9]  Marcel A. Behr,et al.  Mycobacterium avium in the Postgenomic Era , 2007, Clinical Microbiology Reviews.

[10]  K. Khan,et al.  Nontuberculous mycobacterial sensitization in the United States: national trends over three decades. , 2007, American journal of respiratory and critical care medicine.

[11]  Philip Hugenholtz,et al.  NAST: a multiple sequence alignment server for comparative analysis of 16S rRNA genes , 2006, Nucleic Acids Res..

[12]  J. Falkinham,et al.  Effect of Growth in Biofilms on Chlorine Susceptibility of Mycobacterium avium and Mycobacterium intracellulare , 2006, Applied and Environmental Microbiology.

[13]  M. Para,et al.  Aerosols containing Legionella pneumophila generated by shower heads and hot-water faucets , 1985, Applied and environmental microbiology.

[14]  A. Chao,et al.  Estimating the Number of Classes via Sample Coverage , 1992 .

[15]  D. van Soolingen,et al.  Mycobacterium avium in a shower linked to pulmonary disease. , 2008, Journal of water and health.

[16]  Yung-Sung Cheng,et al.  Particle Size Distribution and Inhalation Dose of Shower Water Under Selected Operating Conditions , 2007, Inhalation toxicology.

[17]  F. Portaels,et al.  Mycobacteria in drinking water distribution systems: ecology and significance for human health. , 2005, FEMS microbiology reviews.

[18]  E. Myers,et al.  Basic local alignment search tool. , 1990, Journal of molecular biology.

[19]  D. Lane 16S/23S rRNA sequencing , 1991 .

[20]  G. Stelma,et al.  Molecular Comparison of Mycobacterium avium Isolates from Clinical and Environmental Sources , 2008, Applied and Environmental Microbiology.

[21]  J. Falkinham The changing pattern of nontuberculous mycobacterial disease. , 2003, The Canadian journal of infectious diseases = Journal canadien des maladies infectieuses.

[22]  M. Swanson,et al.  Legionella pneumophila pathogesesis: a fateful journey from amoebae to macrophages. , 2000, Annual review of microbiology.

[23]  N. Wellinghausen,et al.  Detection of Legionellae in Hospital Water Samples by Quantitative Real-Time LightCycler PCR , 2001, Applied and Environmental Microbiology.

[24]  M. Lechevallier,et al.  Factors Influencing Numbers of Mycobacterium avium, Mycobacterium intracellulare, and Other Mycobacteria in Drinking Water Distribution Systems , 2001, Applied and Environmental Microbiology.

[25]  W. Ludwig,et al.  Differentiation of Phylogenetically Related Slowly Growing Mycobacteria Based on 16S-23S rRNA Gene Internal Transcribed Spacer Sequences , 1998, Journal of Clinical Microbiology.

[26]  M. Alary,et al.  Risk factors for contamination of domestic hot water systems by legionellae , 1991, Applied and environmental microbiology.

[27]  Haruo Watanabe,et al.  Specific Detection of Viable Legionella Cells by Combined Use of Photoactivated Ethidium Monoazide and PCR/Real-Time PCR , 2008, Applied and Environmental Microbiology.

[28]  Erko Stackebrandt,et al.  Taxonomic Note: A Place for DNA-DNA Reassociation and 16S rRNA Sequence Analysis in the Present Species Definition in Bacteriology , 1994 .

[29]  J. Falkinham Mycobacterial Aerosols and Respiratory Disease , 2003, Emerging infectious diseases.

[30]  S. Yoshida,et al.  Development of a new seminested PCR method for detection of Legionella species and its application to surveillance of legionellae in hospital cooling tower water , 1997, Applied and environmental microbiology.

[31]  Eugene W. Myers,et al.  Basic local alignment search tool. Journal of Molecular Biology , 1990 .

[32]  Thomas E Hanson,et al.  Methanotrophic bacteria. , 1996, Microbiological reviews.

[33]  N. Cianciotto,et al.  Legionella pneumophila mip gene potentiates intracellular infection of protozoa and human macrophages. , 1992, Proceedings of the National Academy of Sciences of the United States of America.

[34]  S. Field,et al.  Mycobacterium avium complex pulmonary disease in patients without HIV infection. , 2004, Chest.

[35]  P. Suffys,et al.  Detection of mixed infections with Mycobacterium lentiflavum and Mycobacterium avium by molecular genotyping methods. , 2006, Journal of medical microbiology.

[36]  L. Heifets Mycobacterial infections caused by nontuberculous mycobacteria. , 2004, Seminars in respiratory and critical care medicine.

[37]  V. Yu,et al.  Legionnaires' Disease Contracted from Patient Homes: The Coming of the Third Plague? , 2002, European Journal of Clinical Microbiology and Infectious Diseases.

[38]  K. Schleifer,et al.  ARB: a software environment for sequence data. , 2004, Nucleic acids research.

[39]  P. Martikainen,et al.  Survival of Mycobacterium avium, Legionella pneumophila, Escherichia coli, and Caliciviruses in Drinking Water-Associated Biofilms Grown under High-Shear Turbulent Flow , 2007, Applied and Environmental Microbiology.

[40]  G. Stelma,et al.  Persistence of Nontuberculous Mycobacteria in a Drinking Water System after Addition of Filtration Treatment , 2006, Applied and Environmental Microbiology.

[41]  H. Jannasch,et al.  Bacterial Populations in Sea Water as Determined by Different Methods of Enumeration1 , 1959 .

[42]  B. Currie,et al.  Nontuberculous mycobacterial disease in northern Australia: a case series and review of the literature. , 2000, Clinical infectious diseases : an official publication of the Infectious Diseases Society of America.

[43]  R. Wallace,,et al.  Hypersensitivity pneumonitis reaction to Mycobacterium avium in household water. , 2005, Chest.

[44]  L. T. Angenent,et al.  Molecular identification of potential pathogens in water and air of a hospital therapy pool. , 2005, Proceedings of the National Academy of Sciences of the United States of America.

[45]  M. Lechevallier,et al.  Survival of Mycobacterium avium in a model distribution system. , 2004, Water research.

[46]  Eun Jung Lee,et al.  Prevalence of non-tuberculous mycobacteria in a hospital environment. , 2007, The Journal of hospital infection.

[47]  S. Giovannoni,et al.  Bias caused by template annealing in the amplification of mixtures of 16S rRNA genes by PCR , 1996, Applied and environmental microbiology.

[48]  M. Exner,et al.  Prevention and control of health care-associated waterborne infections in health care facilities. , 2005, American journal of infection control.

[49]  C. Mody,et al.  A Legionella pneumophila gene encoding a species-specific surface protein potentiates initiation of intracellular infection , 1989, Infection and immunity.

[50]  N. Pace A molecular view of microbial diversity and the biosphere. , 1997, Science.

[51]  N. Pace,et al.  Culture-Independent Analysis of Indomethacin-Induced Alterations in the Rat Gastrointestinal Microbiota , 2006, Applied and Environmental Microbiology.

[52]  Daniel N. Frank,et al.  XplorSeq: A software environment for integrated management and phylogenetic analysis of metagenomic sequence data , 2008, BMC Bioinformatics.

[53]  Y. Nishiuchi,et al.  The recovery of Mycobacterium avium-intracellulare complex (MAC) from the residential bathrooms of patients with pulmonary MAC. , 2007, Clinical infectious diseases : an official publication of the Infectious Diseases Society of America.

[54]  A. Montiel,et al.  Occurrence of Mycobacteria in Water Treatment Lines and in Water Distribution Systems , 2002, Applied and Environmental Microbiology.