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Zhang Y, Sun R, Yu C, Li J, Lin H, Huang J, Wang Y, Shen X, Jiang Y, Yang C, Xu B. Spatial Heterogeneity of Nontuberculous Mycobacterial Pulmonary Disease in Shanghai: Insights from a Ten-Year Population-Based Study. Int J Infect Dis 2024; 143:107001. [PMID: 38461931 DOI: 10.1016/j.ijid.2024.107001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2023] [Revised: 03/04/2024] [Accepted: 03/05/2024] [Indexed: 03/12/2024] Open
Abstract
OBJECTIVE To investigate the spatial heterogeneity of nontuberculous mycobacterial pulmonary disease (NTM-PD) in Shanghai. METHODS A population-based retrospective study was conducted using presumptive pulmonary tuberculosis surveillance data of Shanghai between 2010 and 2019. The study described the spatial distribution of NTM-PD notification rates, employing hierarchical Bayesian mapping for high-risk areas and the Getis-Ord Gi* statistic to identify hot spots and explore associated factors. RESULTS Of 1652 NTM-PD cases, the most common species was Mycobacterium kansasii complex (MKC) (41.9%), followed by Mycobacterium avium complex (MAC) (27.1%) and Mycobacterium abscessus complex (MABC) (16.2%). MKC-PD patients were generally younger males with a higher incidence of pulmonary cavities, while MAC-PD patients were more often farmers or had a history of tuberculosis treatment. MKC-PD hot spots were primarily located in the areas alongside the Huangpu River, while MAC-PD hot spots were mainly in the western agricultural areas. Patients with MKC-PD and MAC-PD exhibited a higher risk of spatial clustering compared to those with MABC-PD. CONCLUSIONS Different types of NTM-PD exhibit distinct patterns of spatial clustering and are associated with various factors. These findings underscore the importance of environmental and host factors in the epidemic of NTM-PD.
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Affiliation(s)
- Yangyi Zhang
- Department of Epidemiology, School of Public Health and Key Laboratory of Public Health Safety (Ministry of Education), Fudan University, Shanghai, P. R. China; Division of TB and HIV/AIDS Prevention, Shanghai Municipal Center for Disease Control and Prevention, Shanghai, P. R. China; Shanghai Institutes of Preventive Medicine, Shanghai, P. R. China
| | - Ruoyao Sun
- School of Public Health (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Shenzhen, P. R. China
| | - Chenlei Yu
- Division of TB and HIV/AIDS Prevention, Shanghai Municipal Center for Disease Control and Prevention, Shanghai, P. R. China; Shanghai Institutes of Preventive Medicine, Shanghai, P. R. China
| | - Jing Li
- Division of TB and HIV/AIDS Prevention, Shanghai Municipal Center for Disease Control and Prevention, Shanghai, P. R. China; Shanghai Institutes of Preventive Medicine, Shanghai, P. R. China
| | - Honghua Lin
- School of Public Health (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Shenzhen, P. R. China
| | - Jinrong Huang
- School of Public Health (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Shenzhen, P. R. China; Nanshan District Center for Disease Control and Prevention, Shenzhen, P. R. China
| | - Ying Wang
- Nanshan District Center for Disease Control and Prevention, Shenzhen, P. R. China
| | - Xin Shen
- Division of TB and HIV/AIDS Prevention, Shanghai Municipal Center for Disease Control and Prevention, Shanghai, P. R. China; Shanghai Institutes of Preventive Medicine, Shanghai, P. R. China
| | - Yuan Jiang
- Division of TB and HIV/AIDS Prevention, Shanghai Municipal Center for Disease Control and Prevention, Shanghai, P. R. China; Shanghai Institutes of Preventive Medicine, Shanghai, P. R. China
| | - Chongguang Yang
- School of Public Health (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Shenzhen, P. R. China; Nanshan District Center for Disease Control and Prevention, Shenzhen, P. R. China
| | - Biao Xu
- Department of Epidemiology, School of Public Health and Key Laboratory of Public Health Safety (Ministry of Education), Fudan University, Shanghai, P. R. China.
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Glauser KG, Kelley RE, Leonard WJ, Hendrix J, Petri S, Tong EI, Chan YL, Lipner EM, Dawrs SN, Honda JR. Common Features of Environmental Mycobacterium chelonae from Colorado Using Partial and Whole Genomic Sequence Analyses. Curr Microbiol 2024; 81:69. [PMID: 38238596 PMCID: PMC10796651 DOI: 10.1007/s00284-023-03589-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2023] [Accepted: 12/12/2023] [Indexed: 01/22/2024]
Abstract
Nontuberculous mycobacteria (NTM) are environmentally acquired opportunistic pathogens that cause chronic lung disease in susceptible individuals. While presumed to be ubiquitous in built and natural environments, NTM environmental studies are limited. While environmental sampling campaigns have been performed in geographic areas of high NTM disease burden, NTM species diversity is less defined among areas of lower disease burden like Colorado. In Colorado, metals such as molybdenum have been correlated with increased risk for NTM infection, yet environmental NTM species diversity has not yet been widely studied. Based on prior regression modeling, three areas of predicted high, moderate, and low NTM risk were identified for environmental sampling in Colorado. Ice, plumbing biofilms, and sink tap water samples were collected from publicly accessible freshwater sources. All samples were microbiologically cultured and NTM were identified using partial rpoB gene sequencing. From these samples, areas of moderate risk were more likely to be NTM positive. NTM recovery from ice was more common than recovery from plumbing biofilms or tap water. Overall, nine different NTM species were identified, including clinically important Mycobacterium chelonae. MinION technology was used to whole genome sequence and compare mutational differences between six M. chelonae genomes, representing three environmental isolates from this study and three other M. chelonae isolates from other sources. Drug resistance genes and prophages were common findings among environmentally derived M. chelonae, promoting the need for expanded environmental sampling campaigns to improve our current understanding of NTM species abundance while opening new avenues for improved targeted drug therapies.
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Affiliation(s)
- Kayden G Glauser
- Department of Science, Principles of Experimental Design in Biotechnology, Rock Canyon High School, Littleton, CO, 80124, USA
| | - Reagan E Kelley
- Department of Science, Principles of Experimental Design in Biotechnology, Rock Canyon High School, Littleton, CO, 80124, USA
| | - William J Leonard
- Department of Science, Principles of Experimental Design in Biotechnology, Rock Canyon High School, Littleton, CO, 80124, USA
| | - Jo Hendrix
- Computational Bioscience Program, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - Suzanne Petri
- Department of Science, Principles of Experimental Design in Biotechnology, Rock Canyon High School, Littleton, CO, 80124, USA
| | - Eric I Tong
- Aina Informatics Network, 'Iolani School, Honolulu, HI, 96826, USA
| | - Yvonne L Chan
- Aina Informatics Network, 'Iolani School, Honolulu, HI, 96826, USA
| | - Ettie M Lipner
- National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Stephanie N Dawrs
- Center for Genes, Environment and Health, National Jewish Health, Denver, CO, 80206, USA
| | - Jennifer R Honda
- Department of Cellular and Molecular Biology, School of Medicine, University of Texas at Tyler Health Science Center, Tyler, TX, 75708, USA.
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Dawrs SN, Virdi R, Norton GJ, Elias T, Hasan NA, Robinson S, Matriz J, Epperson LE, Glickman CM, Beagle S, Crooks JL, Nelson ST, Chan ED, Damby DE, Strong M, Honda JR. Hawaiian Volcanic Ash, an Airborne Fomite for Nontuberculous Mycobacteria. GEOHEALTH 2024; 8:e2023GH000889. [PMID: 38161597 PMCID: PMC10757267 DOI: 10.1029/2023gh000889] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Revised: 12/04/2023] [Accepted: 12/07/2023] [Indexed: 01/03/2024]
Abstract
Nontuberculous mycobacteria (NTM) are environmentally acquired opportunistic pathogens that can cause chronic lung disease. Within the U.S., Hawai'i shows the highest prevalence rates of NTM lung infections. Here, we investigated a potential role for active volcanism at the Kīlauea Volcano located on Hawai'i Island in promoting NTM growth and diversity. We recovered NTM that are known to cause lung disease from plumbing biofilms and soils collected from the Kīlauea environment. We also discovered viable Mycobacterium avium, Mycobacterium abscessus, and Mycobacterium intracellulare subsp. chimaera on volcanic ash collected during the 2018 Kīlauea eruption. Analysis of soil samples showed that NTM prevalence is positively associated with bulk content of phosphorus, sulfur, and total organic carbon. In growth assays, we showed that phosphorus utilization is essential for proliferation of Kīlauea-derived NTM, and demonstrate that NTM cultured with volcanic ash adhere to ash surfaces and remain viable. Ambient dust collected on O'ahu concurrent with the 2018 eruption contained abundant fresh volcanic glass, suggestive of inter-island ash transport. Phylogenomic analyses using whole genome sequencing revealed that Kīlauea-derived NTM are genetically similar to respiratory isolates identified on other Hawaiian Islands. Consequently, we posit that volcanic eruptions could redistribute environmental microorganisms over large scales. While additional studies are needed to confirm a direct role of ash in NTM dispersal, our results suggest that volcanic particulates harbor and can redistribute NTM and should therefore be studied as a fomite for these burgeoning, environmentally acquired respiratory infections.
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Affiliation(s)
| | - Ravleen Virdi
- Center for GenesEnvironmentand HealthNational Jewish HealthDenverCOUSA
- Now at Corgenix Medical CorporationBroomfieldCOUSA
| | - Grant J. Norton
- Center for GenesEnvironmentand HealthNational Jewish HealthDenverCOUSA
- Now at University of CaliforniaSan DiegoCAUSA
| | - Tamar Elias
- U.S. Geological SurveyVolcano Science CenterHawaiian Volcano ObservatoryHiloHawai'iUSA
| | - Nabeeh A. Hasan
- Center for GenesEnvironmentand HealthNational Jewish HealthDenverCOUSA
| | - Schuyler Robinson
- Department of Geological SciencesBrigham Young UniversityProvoUTUSA
- Now at GSI EnvironmentalHoustonTXUSA
| | - Jobel Matriz
- Department of MicrobiologyUniversity of Hawai'i ManoaHonoluluHawai'iUSA
- Now at National Institutes of HealthBethesdaMDUSA
| | | | - Cody M. Glickman
- Center for GenesEnvironmentand HealthNational Jewish HealthDenverCOUSA
- Now at EndolytixBeverlyMEUSA
| | - Sean Beagle
- Center for GenesEnvironmentand HealthNational Jewish HealthDenverCOUSA
- Now at Lockheed MartinKing of PrussiaPAUSA
| | - James L. Crooks
- Division of Biostatistics and BioinformaticsNational Jewish HealthDenverCOUSA
- Department of EpidemiologyColorado School of Public HealthAuroraCOUSA
| | | | - Edward D. Chan
- Medicine and Academic AffairsNational Jewish HealthDenverCOUSA
- Division of Pulmonary Sciences and Critical Care MedicineUniversity of Colorado Anschutz Medical CampusAuroraCOUSA
- Department of MedicineRocky Mountain Regional Veterans Affairs Medical CenterAuroraCOUSA
| | - David E. Damby
- U.S. Geological SurveyVolcano Science CenterMenlo ParkCAUSA
| | - Michael Strong
- Center for GenesEnvironmentand HealthNational Jewish HealthDenverCOUSA
| | - Jennifer R. Honda
- Center for GenesEnvironmentand HealthNational Jewish HealthDenverCOUSA
- Department of Cellular and Molecular BiologySchool of MedicineUniversity of Texas Health Science Center at TylerTylerTXUSA
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Honda JR. Environmental Sources and Transmission of Nontuberculous Mycobacteria. Clin Chest Med 2023; 44:661-674. [PMID: 37890909 DOI: 10.1016/j.ccm.2023.07.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/29/2023]
Abstract
The field of environmental nontuberculous mycobacteria (NTM) is benefiting from a new era of genomics that has catapulted our understanding of preferred niches, transmission, and outbreak investigations. The ability to forecast environmental features that promote or reduce environmental NTM prevalence will greatly improve with coordinated environmental sampling and by elevating the necessity for uniform disease notifications. Studies that synergize environmental biology, isolate notifications, and comparative genomics in prospective, longitudinal studies, particularly during climate changes and weather events, will be useful to solve longstanding NTM public health quandaries.
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Affiliation(s)
- Jennifer R Honda
- Department of Cellular and Molecular Biology, University of Texas Health Science Center at Tyler, 11937 US Hwy 271, BMR Building, Tyler, TX 75708, USA.
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Hendrix J, Epperson LE, Tong EI, Chan YL, Hasan NA, Dawrs SN, Norton GJ, Virdi R, Crooks JL, Chan ED, Honda JR, Strong M. Complete genome assembly of Hawai'i environmental nontuberculous mycobacteria reveals unexpected co-isolation with methylobacteria. PLoS One 2023; 18:e0291072. [PMID: 37703253 PMCID: PMC10499228 DOI: 10.1371/journal.pone.0291072] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Accepted: 08/22/2023] [Indexed: 09/15/2023] Open
Abstract
Nontuberculous mycobacteria (NTM) are ubiquitous environmental opportunistic pathogens that can cause chronic lung disease. Within the United States, Hawai'i has the highest incidence of NTM lung disease, though the precise reasons are yet to be fully elucidated. One possibility is the high prevalence of NTM in the Hawai'i environment acting as a potential reservoir for opportunistic NTM infections. Through our previous initiatives to collect and characterize NTM in Hawai'i, community scientists of Hawai'i have collected thousands of environmental samples for sequencing. Here, these community scientists were invited for the first time into a high school lab in O'ahu for a genomic sequencing workshop, where participants sequenced four of the collected isolate genomic samples using the Oxford Nanopore Technologies MinION sequencer. Participants generated high quality long read data that when combined with short read Illumina data yielded complete bacterial genomic assemblies suitable for in-depth analysis. The gene annotation analysis identified a suite of genes that might help NTM thrive in the Hawai'i environment. Further, we found evidence of co-occurring methylobacteria, revealed from the sequencing data, suggesting that in some cases methylobacteria and NTM may coexist in the same niche, challenging previously accepted paradigms. The sequencing efforts presented here generated novel insights regarding the potential survival strategies and microbial interactions of NTM in the geographic hot spot of Hawai'i. We highlight the contributions of community scientists and present an activity that can be reimplemented as a workshop or classroom activity by other research groups to engage their local communities.
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Affiliation(s)
- Jo Hendrix
- Center for Genes, Environment, and Health, National Jewish Health, Denver, CO, United States of America
- Computational Bioscience Program, University of Colorado, Anschutz Medical Campus, Aurora, CO, United States of America
| | - L. Elaine Epperson
- Center for Genes, Environment, and Health, National Jewish Health, Denver, CO, United States of America
| | - Eric I. Tong
- ‘Iolani School, Honolulu, Hawai’i, United States of America
| | - Yvonne L. Chan
- ‘Iolani School, Honolulu, Hawai’i, United States of America
| | - Nabeeh A. Hasan
- Center for Genes, Environment, and Health, National Jewish Health, Denver, CO, United States of America
| | - Stephanie N. Dawrs
- Center for Genes, Environment, and Health, National Jewish Health, Denver, CO, United States of America
| | - Grant J. Norton
- Center for Genes, Environment, and Health, National Jewish Health, Denver, CO, United States of America
| | - Ravleen Virdi
- Center for Genes, Environment, and Health, National Jewish Health, Denver, CO, United States of America
| | - James L. Crooks
- Division of Biostatistics and Bioinformatics, National Jewish Health, Denver, CO, United States of America
- Department of Epidemiology, Colorado School of Public Health, Aurora, CO, United States of America
| | - Edward D. Chan
- Department of Medicine and Academic Affairs, National Jewish Health, Denver, CO, United States of America
- Division of Pulmonary Sciences and Critical Care Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States of America
- Department of Medicine, Rocky Mountain Regional Veterans Affairs Medical Center, Aurora, CO, United States of America
| | - Jennifer R. Honda
- Department of Cellular and Molecular Biology, School of Medicine, University of Texas Health Science Center at Tyler, Tyler, TX, United States of America
| | - Michael Strong
- Center for Genes, Environment, and Health, National Jewish Health, Denver, CO, United States of America
- Computational Bioscience Program, University of Colorado, Anschutz Medical Campus, Aurora, CO, United States of America
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Mercaldo RA, Marshall JE, Cangelosi GA, Donohue M, Falkinham JO, Fierer N, French JP, Gebert MJ, Honda JR, Lipner EM, Marras TK, Morimoto K, Salfinger M, Stout J, Thomson R, Prevots DR. Environmental risk of nontuberculous mycobacterial infection: Strategies for advancing methodology. Tuberculosis (Edinb) 2023; 139:102305. [PMID: 36706504 PMCID: PMC10023322 DOI: 10.1016/j.tube.2023.102305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 12/27/2022] [Accepted: 01/04/2023] [Indexed: 01/11/2023]
Abstract
The National Institute of Allergy and Infectious Diseases organized a symposium in June 2022, to facilitate discussion of the environmental risks for nontuberculous mycobacteria exposure and disease. The expert researchers presented recent studies and identified numerous research gaps. This report summarizes the discussion and identifies six major areas of future research related to culture-based and culture independent laboratory methods, alternate culture media and culturing conditions, frameworks for standardized laboratory methods, improved environmental sampling strategies, validation of exposure measures, and availability of high-quality spatiotemporal data.
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Affiliation(s)
- Rachel A Mercaldo
- Division of Intramural Research, Epidemiology and Population Studies Unit, NIAID, NIH, Rockville, MD, USA.
| | - Julia E Marshall
- Division of Intramural Research, Epidemiology and Population Studies Unit, NIAID, NIH, Rockville, MD, USA.
| | - Gerard A Cangelosi
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA, USA.
| | - Maura Donohue
- United States Environmental Protection Agency, Center for Environmental Solutions and Emergency Response, Cincinnati, OH, USA.
| | | | - Noah Fierer
- Department of Ecology and Evolutionary Biology, Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA.
| | - Joshua P French
- Department of Mathematical and Statistical Sciences, University of Colorado Denver, Denver, CO, USA.
| | - Matthew J Gebert
- Department of Ecology and Evolutionary Biology, Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA.
| | - Jennifer R Honda
- Center for Genes, Environment, and Health, National Jewish Health, Denver, CO, USA.
| | - Ettie M Lipner
- Division of Intramural Research, Epidemiology and Population Studies Unit, NIAID, NIH, Rockville, MD, USA.
| | - Theodore K Marras
- Department of Medicine, University of Toronto and University Health Network, Toronto, Canada.
| | - Kozo Morimoto
- Division of Clinical Research, Fukujuji Hospital, Japan Anti-Tuberculosis Association, Tokyo, Japan.
| | - Max Salfinger
- College of Public Health & Morsani College of Medicine, University of South Florida, Tampa, FL, USA.
| | - Janet Stout
- Special Pathogens Laboratory, Pittsburgh, PA, USA; Department of Civil and Environmental Engineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, PA, USA.
| | - Rachel Thomson
- Gallipoli Medical Research Institute & Greenslopes Clinical School, The University of Queensland, Brisbane, Australia.
| | - D Rebecca Prevots
- Division of Intramural Research, Epidemiology and Population Studies Unit, NIAID, NIH, Rockville, MD, USA.
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Vanadium in groundwater aquifers increases the risk of MAC pulmonary infection in O’ahu, Hawai’i. Environ Epidemiol 2022; 6:e220. [DOI: 10.1097/ee9.0000000000000220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Revised: 06/15/2022] [Accepted: 06/15/2022] [Indexed: 11/25/2022] Open
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Blakney RA, Ricotta EE, Frankland TB, Honda S, Zelazny A, Mayer-Barber KD, Dean SG, Follmann D, Olivier KN, Daida YG, Prevots DR. Incidence of Nontuberculous Mycobacterial Pulmonary Infection, by Ethnic Group, Hawaii, USA, 2005-2019. Emerg Infect Dis 2022; 28:1543-1550. [PMID: 35876462 PMCID: PMC9328927 DOI: 10.3201/eid2808.212375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
To further clarify differences in the risk for nontuberculous mycobacterial pulmonary infection (NTM-PI) among ethnic populations in Hawaii, USA, we conducted a retrospective cohort study among beneficiaries of Kaiser Permanente Hawaii (KPH). We abstracted demographic, socioeconomic, clinical, and microbiological data from KPH electronic health records for 2005-2019. An NTM-PI case-patient was defined as a person from whom >1 NTM pulmonary isolate was obtained. We performed Cox proportional hazards regression to estimate incidence of NTM-PI while controlling for confounders. Across ethnic groups, risk for NTM-PI was higher among persons who were underweight (body mass index [BMI] <18.5 kg/m2). Among beneficiaries who self-identified as any Asian ethnicity, risk for incident NTM-PI was increased by 30%. Low BMI may increase susceptibility to NTM-PI, and risk may be higher for persons who self-identify as Asian, independent of BMI.
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Soil Properties and Moisture Synergistically Influence Nontuberculous Mycobacterial Prevalence in Natural Environments of Hawai'i. Appl Environ Microbiol 2022; 88:e0001822. [PMID: 35435715 DOI: 10.1128/aem.00018-22] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Nontuberculous mycobacteria (NTM) are opportunistic pathogens that cause chronic pulmonary disease (PD). NTM infections are thought to be acquired from the environment; however, the basal environmental factors that drive and sustain NTM prevalence are not well understood. The highest prevalence of NTM PD cases in the United States is reported from Hawai'i, which is unique in its climate and soil composition, providing an opportunity to investigate the environmental drivers of NTM prevalence. We used microbiological sampling and spatial logistic regression complemented with fine-scale soil mineralogy to model the probability of NTM presence across the natural landscape of Hawai'i. Over 7 years, we collected and microbiologically cultured 771 samples from 422 geographic sites in natural areas across the Hawaiian Islands for the presence of NTM. NTM were detected in 210 of these samples (27%), with Mycobacterium abscessus being the most frequently isolated species. The probability of NTM presence was highest in expansive soils (those that swell with water) with a high water balance (>1-m difference between rainfall and evapotranspiration) and rich in Fe-oxides/hydroxides. We observed a positive association between NTM presence and iron in wet soils, supporting past studies, but no such association in dry soils. High soil-water balance may facilitate underground movement of NTM into the aquifer system, potentially compounded by expansive capabilities allowing crack formation under drought conditions, representing further possible avenues for aquifer infiltration. These results suggest both precipitation and soil properties are mechanisms by which surface NTM may reach the human water supply. IMPORTANCE Nontuberculous mycobacteria (NTM) are ubiquitous in the environment, being found commonly in soils and natural bodies of freshwater. However, little is known about the environmental niches of NTM and how they relate to NTM prevalence in homes and other human-dominated areas. To characterize NTM environmental associations, we collected and cultured 771 samples from 422 geographic sites in natural areas across Hawai'i, the U.S. state with the highest prevalence of NTM pulmonary disease. We show that the environmental niches of NTM are most associated with highly expansive, moist soils containing high levels of iron oxides/hydroxides. Understanding the factors associated with NTM presence in the natural environment will be crucial for identifying potential mechanisms and risk factors associated with NTM infiltration into water supplies, which are ultimately piped into homes where most exposure risk is thought to occur.
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