1
|
Nduba V, Njagi LN, Murithi W, Mwongera Z, Byers J, Logioia G, Peterson G, Segnitz RM, Fennelly K, Hawn TR, Horne DJ. Mycobacterium tuberculosis cough aerosol culture status associates with host characteristics and inflammatory profiles. Nat Commun 2024; 15:7604. [PMID: 39217183 PMCID: PMC11365933 DOI: 10.1038/s41467-024-52122-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Accepted: 08/27/2024] [Indexed: 09/04/2024] Open
Abstract
Interrupting transmission events is critical to tuberculosis control. Cough-generated aerosol cultures predict tuberculosis transmission better than microbiological or clinical markers. We hypothesize that highly infectious individuals with pulmonary tuberculosis (positive for cough aerosol cultures) have elevated inflammatory markers and unique transcriptional profiles compared to less infectious individuals. We performed a prospective, longitudinal study using cough aerosol sampling system. We enrolled 142 participants with treatment-naïve pulmonary tuberculosis in Kenya and assessed the association of clinical, microbiologic, and immunologic characteristics with Mycobacterium tuberculosis aerosolization and transmission in 129 household members. Contacts of the forty-three aerosol culture-positive participants (30%) are more likely to have a positive interferon-gamma release assay (85% vs 53%, P = 0.006) and higher median IFNγ level (P < 0.001, 4.28 IU/ml (1.77-5.91) vs. 0.71 (0.01-3.56)) compared to aerosol culture-negative individuals. We find that higher bacillary burden, younger age, larger mean upper arm circumference, and host inflammatory profiles, including elevated serum C-reactive protein and lower plasma TNF levels, associate with positive cough aerosol cultures. Notably, we find pre-treatment whole blood transcriptional profiles associate with aerosol culture status, independent of bacillary load. These findings suggest that tuberculosis infectiousness is associated with epidemiologic characteristics and inflammatory signatures and that these features may identify highly infectious persons.
Collapse
Affiliation(s)
- Videlis Nduba
- Centre for Respiratory Diseases Research, Kenya Medical Research Institute, Nairobi, Kenya
| | - Lilian N Njagi
- Centre for Respiratory Diseases Research, Kenya Medical Research Institute, Nairobi, Kenya
| | - Wilfred Murithi
- Centre for Respiratory Diseases Research, Kenya Medical Research Institute, Nairobi, Kenya
| | - Zipporah Mwongera
- Centre for Respiratory Diseases Research, Kenya Medical Research Institute, Nairobi, Kenya
| | - Jodi Byers
- Department of Global Health, University of Washington, Seattle, WA, USA
| | - Gisella Logioia
- Department of Medicine, University of Washington, Seattle, WA, USA
| | - Glenna Peterson
- Department of Medicine, University of Washington, Seattle, WA, USA
| | - R Max Segnitz
- Department of Medicine, University of Washington, Seattle, WA, USA
| | - Kevin Fennelly
- Division of Intramural Research, National Heart, Lung and Blood Institute (NHLBI), National Institutes of Health, Bethesda, MD, USA
| | - Thomas R Hawn
- Department of Medicine, University of Washington, Seattle, WA, USA
| | - David J Horne
- Department of Global Health, University of Washington, Seattle, WA, USA.
- Department of Medicine, University of Washington, Seattle, WA, USA.
| |
Collapse
|
2
|
Fortune SM. The Titanic question in TB control: Should we worry about the bummock? Proc Natl Acad Sci U S A 2024; 121:e2403321121. [PMID: 38527210 PMCID: PMC10998566 DOI: 10.1073/pnas.2403321121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/27/2024] Open
Affiliation(s)
- Sarah M. Fortune
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, MA02115
| |
Collapse
|
3
|
Horne D, Nduba V, Njagi L, Murithi W, Mwongera Z, Logioia G, Peterson G, Segnitz RM, Fennelly K, Hawn T. Tuberculosis Infectiousness is Associated with Distinct Clinical and Inflammatory Profiles. RESEARCH SQUARE 2024:rs.3.rs-3722244. [PMID: 38328225 PMCID: PMC10849670 DOI: 10.21203/rs.3.rs-3722244/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2024]
Abstract
Interrupting transmission events to prevent new acquisition of infection and disease is a critical part of tuberculosis (TB) control efforts. However, knowledge gaps in understanding the biology and determinants of TB transmission, including poor estimates of individual infectiousness and the lack of accurate and convenient biomarkers, undermine efforts to develop interventions. Cough-generated aerosol cultures have been found to predict TB transmission better than any microbiological or clinical markers in cohorts from Uganda and Brazil. We hypothesized that highly infectious individuals with pulmonary TB (defined as positive for cough aerosol cultures) have elevated inflammatory markers and unique transcriptional profiles compared to less infectious individuals (negative for cough aerosol cultures). We performed a prospective, longitudinal study using a cough aerosol sampling system as in other studies. We enrolled 142 participants with treatment-naïve pulmonary TB in Nairobi, Kenya, and assessed the association of clinical, microbiologic, and immunologic characteristics with Mtb aerosolization and transmission in 143 household members. Contacts of the forty-three aerosol culture-positive participants (30%) were more likely to have a positive IGRA (85% vs 53%, P = 0.005) and a higher median IGRA IFNγ level (P < 0.001, median 4.25 IU/ml (0.90-5.91) vs. 0.71 (0.01-3.56)) compared to aerosol culture-negative individuals. We found that higher bacillary burden, younger age, and larger mean upper arm circumference were associated with positive aerosol cultures. In addition, novel host inflammatory profiles, including elevated serum C-reactive protein and sputum cytokines, were associated with aerosol culture status. Notably, we found pre-treatment whole blood transcriptional profiles associated with aerosol culture status, independent of bacillary load. Together, these findings suggest that TB infectiousness is associated with epidemiologic characteristics and inflammatory signatures and that these features may be used to identify highly infectious persons. These results provide new public health tools and insights into TB pathogenesis.
Collapse
Affiliation(s)
| | - Videlis Nduba
- Centre for Respiratory Diseases Research, Kenya Medical Research Institute
| | - Lilian Njagi
- Centre for Respiratory Diseases Research, Kenya Medical Research Institute
| | - Wilfred Murithi
- Centre for Respiratory Diseases Research, Kenya Medical Research Institute
| | - Zipporah Mwongera
- Centre for Respiratory Diseases Research, Kenya Medical Research Institute
| | | | | | | | - Kevin Fennelly
- National Heart, Lung, and Blood Institute (NHLBI), National Institutes of Health (NIH)
| | | |
Collapse
|
4
|
Venkatappa T, Shen D, Ayala A, Li R, Sorri Y, Punnoose R, Katz D. Association of Mycobacterium tuberculosis infection test results with risk factors for tuberculosis transmission. J Clin Tuberc Other Mycobact Dis 2023; 33:100386. [PMID: 37426113 PMCID: PMC10328964 DOI: 10.1016/j.jctube.2023.100386] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/11/2023] Open
Abstract
Background Close contacts infected with Mycobacterium tuberculosis are at high risk of tuberculosis (TB) disease and a priority for preventive treatment. Three tests measure infection: two interferon-gamma release assays (IGRAs) and the tuberculin skin test (TST). The objective of our study was to assess the association of positive test results in contacts with infectiousness of the presumed TB source case. Methods Contacts in a cohort study at 10 United States sites received both IGRAs (QuantiFERON-TB Gold In-Tube (QFT-GIT) and T-SPOT.TB (T-SPOT)) and TST. We defined test conversion as negative for all tests at baseline and positive for at least one on retest. Risk ratios (RR) and 95% confidence intervals (CI) assessed association of positive test results with increased infectiousness of the TB case-defined as acid-fast bacilli (AFB) on sputum microscopy or cavities on chest radiographs- and contact demographics. Results Adjusted for contacts' age, nativity, sex, and race, IGRAs (QFT-GIT RR = 6.1, 95% CI 1.7-22.2; T-SPOT RR = 9.4, 95% CI 1.1-79.1), but not TST (RR = 1.7, 95% CI 0.8-3.7), were more likely to convert among contacts exposed to persons with cavitary TB disease. Conclusions Because IGRA conversions in contacts are associated with infectiousness of the TB case, their use may improve efficiency of health department contact investigations by focusing efforts on those likely to benefit from preventive treatment in the United States.
Collapse
Affiliation(s)
- Thara Venkatappa
- Division of Tuberculosis Elimination, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Dan Shen
- Maricopa County Department of Public Health, 1645 E Roosevelt St, Phoenix, AZ 85006, USA
| | - Aurimar Ayala
- Maricopa County Department of Public Health, 1645 E Roosevelt St, Phoenix, AZ 85006, USA
| | - Rongxia Li
- Division of Tuberculosis Elimination, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Yoseph Sorri
- Seattle-King County Public Health TB Clinic, 325 9 Ave HMC Box 359776, Seattle, WA 98104, USA
| | - Rose Punnoose
- Peraton, Atlanta, 2800 Century Parkway, NE, GA 30345, USA
| | - Dolly Katz
- Division of Tuberculosis Elimination, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | | |
Collapse
|
5
|
Abstract
Coughing is a dynamic physiological process resulting from input of vagal sensory neurons innervating the airways and perceived airway irritation. Although cough serves to protect and clear the airways, it can also be exploited by respiratory pathogens to facilitate disease transmission. Microbial components or infection-induced inflammatory mediators can directly interact with sensory nerve receptors to induce a cough response. Analysis of cough-generated aerosols and transmission studies have further demonstrated how infectious disease is spread through coughing. This review summarizes the neurophysiology of cough, cough induction by respiratory pathogens and inflammation, and cough-mediated disease transmission.
Collapse
Affiliation(s)
- Kubra F Naqvi
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA;
| | - Stuart B Mazzone
- Department of Anatomy and Physiology, University of Melbourne, Victoria, Australia
| | - Michael U Shiloh
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA;
- Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| |
Collapse
|
6
|
Wang Z, Li H, Song S, Sun H, Dai X, Chen M, Xu H, Zhang H, Pang Y. Transmission of tuberculosis in an incarcerated population during the subclinical period: A cross-sectional study in Qingdao, China. Front Public Health 2023; 11:1098519. [PMID: 36761133 PMCID: PMC9905226 DOI: 10.3389/fpubh.2023.1098519] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 01/06/2023] [Indexed: 01/26/2023] Open
Abstract
Objectives As a closed gathering place, prison is the cradle of tuberculosis (TB) outbreak. Therefore, the analysis of the prevalence rate and risk factors of latent tuberculosis infection (LTBI) in prison will be a necessary measure to intervene in the spread of tuberculosis. Methods In this study, we consecutively recruited 506 adult prisoners in Qingdao to carry out this cross-sectional study. TB and LTBI were screened by IGRA, X-ray, X-pert, sputum smear and culture. Results A total of 17 TB, 101 LTBI and 388 HC were identified, with an infection rate of 23.32% (118/506) and a TB incidence rate of 3282/100,000 population. Age, malnutrition and inmates living with TB prisoners were risk factors for LTBI. Additionally, most TB cases (70.59%, 12/17) were subclinical tuberculosis (STB), contributing significantly to TB transmission. Conclusion Our results demonstrate that the transmission efficiency of asymptomatic patients is not essentially different from that of symptomatic patients, indicating that TB transmission occurs during the subclinical period. Our findings highlight the need to strengthen active case-finding strategies to increase TB case detection in this population.
Collapse
Affiliation(s)
- Zhongdong Wang
- 1Qingdao Municipal Center for Disease Control and Prevention, Qingdao, China
| | - Haoran Li
- 2Department of Bacteriology and Immunology, Beijing Chest Hospital, Capital Medical University/Beijing Tuberculosis and Thoracic Tumor Research Institute, Beijing, China
| | - Song Song
- 1Qingdao Municipal Center for Disease Control and Prevention, Qingdao, China
| | - Haiyan Sun
- 1Qingdao Municipal Center for Disease Control and Prevention, Qingdao, China
| | - Xiaoqi Dai
- 1Qingdao Municipal Center for Disease Control and Prevention, Qingdao, China
| | - Meng Chen
- 1Qingdao Municipal Center for Disease Control and Prevention, Qingdao, China
| | - Honghong Xu
- 1Qingdao Municipal Center for Disease Control and Prevention, Qingdao, China
| | - Huaqiang Zhang
- 1Qingdao Municipal Center for Disease Control and Prevention, Qingdao, China,Huaqiang Zhang ✉
| | - Yu Pang
- 2Department of Bacteriology and Immunology, Beijing Chest Hospital, Capital Medical University/Beijing Tuberculosis and Thoracic Tumor Research Institute, Beijing, China,*Correspondence: Yu Pang ✉
| |
Collapse
|
7
|
Gupta T, Somanna N, Rowe T, LaGatta M, Helms S, Owino SO, Jelesijevic T, Harvey S, Jacobs W, Voss T, Sakamoto K, Day C, Whalen C, Karls R, He B, Tompkins SM, Bakre A, Ross T, Quinn FD. Ferrets as a model for tuberculosis transmission. Front Cell Infect Microbiol 2022; 12:873416. [PMID: 36051240 PMCID: PMC9425069 DOI: 10.3389/fcimb.2022.873416] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 07/11/2022] [Indexed: 11/26/2022] Open
Abstract
Even with the COVID-19 pandemic, tuberculosis remains a leading cause of human death due to a single infectious agent. Until successfully treated, infected individuals may continue to transmit Mycobacterium tuberculosis bacilli to contacts. As with other respiratory pathogens, such as SARS-CoV-2, modeling the process of person-to-person transmission will inform efforts to develop vaccines and therapies that specifically impede disease transmission. The ferret (Mustela furo), a relatively inexpensive, small animal has been successfully employed to model transmissibility, pathogenicity, and tropism of influenza and other respiratory disease agents. Ferrets can become naturally infected with Mycobacterium bovis and are closely related to badgers, well known in Great Britain and elsewhere as a natural transmission vehicle for bovine tuberculosis. Herein, we report results of a study demonstrating that within 7 weeks of intratracheal infection with a high dose (>5 x 103 CFU) of M. tuberculosis bacilli, ferrets develop clinical signs and pathological features similar to acute disease reported in larger animals, and ferrets infected with very-high doses (>5 x 104 CFU) develop severe signs within two to four weeks, with loss of body weight as high as 30%. Natural transmission of this pathogen was also examined. Acutely-infected ferrets transmitted M. tuberculosis bacilli to co-housed naïve sentinels; most of the sentinels tested positive for M. tuberculosis in nasal washes, while several developed variable disease symptomologies similar to those reported for humans exposed to an active tuberculosis patient in a closed setting. Transmission was more efficient when the transmitting animal had a well-established acute infection. The findings support further assessment of this model system for tuberculosis transmission including the testing of prevention measures and vaccine efficacy.
Collapse
Affiliation(s)
- Tuhina Gupta
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
| | - Naveen Somanna
- Molecular Analytics R&D, GlaxoSmithKline Vaccines, Rockville, MD, United States
| | - Thomas Rowe
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
- Influenza Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, GA, United States
| | - Monica LaGatta
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
| | - Shelly Helms
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
| | - Simon Odera Owino
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
| | - Tomislav Jelesijevic
- Department of Comparative Biomedical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA, United States
| | - Stephen Harvey
- Animal Resources Program, University of Georgia, Athens, GA, United States
| | - Wayne Jacobs
- Animal Resources Program, University of Georgia, Athens, GA, United States
| | - Thomas Voss
- Merck Research Laboratories, West Point, PA, United States
| | - Kaori Sakamoto
- Department of Pathology, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
| | - Cheryl Day
- Department of Microbiology and Immunology, Emory University School of Medicine, Atlanta, GA, United States
| | - Christopher Whalen
- Department of Epidemiology and Biostatistics, College of Public Health, University of Georgia, Athens, GA, United States
| | - Russell Karls
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
| | - Biao He
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
| | - S. Mark Tompkins
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
| | - Abhijeet Bakre
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
| | - Ted Ross
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
| | - Frederick D. Quinn
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
- *Correspondence: Frederick D. Quinn,
| |
Collapse
|
8
|
Redmann RK, Kaushal D, Golden N, Threeton B, Killeen SZ, Kuehl PJ, Roy CJ. Particle Dynamics and Bioaerosol Viability of Aerosolized Bacillus Calmette-Guérin Vaccine Using Jet and Vibrating Mesh Clinical Nebulizers. J Aerosol Med Pulm Drug Deliv 2022; 35:50-56. [PMID: 34619040 PMCID: PMC8867098 DOI: 10.1089/jamp.2021.0030] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Background: Bacillus Calmette-Guérin (BCG) is a vaccine used to protect against tuberculosis primarily in infants to stop early infection in areas of the world where the disease is endemic. Normally administered as a percutaneous injection, BCG is a live significantly attenuated bacteria that is now being investigated for its potential within an inhalable vaccine formulation. This study investigates the feasibility and performance of two jet and two vibrating mesh nebulizers aerosolizing BCG and the resulting particle characteristics and residual viability of the bacteria postaerosolization. Methods: A jet nebulizer (Collison), outfitted either with a 3- or 6-jet head, was compared with two clinical nebulizers, the vibrating mesh Omron MicroAir and Aerogen Solo devices. Particle characteristics, including aerodynamic particle sizing, was performed on all devices within a common aerosol chamber configuration and comparable BCG innocula concentrations. Integrated aerosol samples were collected for each generator and assayed for bacterial viability using conventional microbiological technique. Results: A batch lot of BCG (Danish) was grown to titer and used in all generator assessments. Aerosol particles within the respirable range were generated from all nebulizers at four different concentrations of BCG. The jet nebulizers produced a uniformly smaller particle size than the vibrating mesh devices, although particle concentrations by mass were similar across all devices tested with the exception of the Aerogen Solo, which resulted in a low concentration of BCG aerosols. Conclusions: The resulting measured viable BCG aerosol concentration fraction produced by each device approximated one another; however, a measurable decrease of efficiency and overall viability reduction in the jet nebulizer was observed in higher BCG inoculum starting concentrations, whereas the vibrating mesh nebulizer returned a remarkably stable viable aerosol fraction irrespective of inoculum concentration.
Collapse
Affiliation(s)
- Rachel K. Redmann
- Infectious Disease Aerobiology, Division of Microbiology, Tulane National Primate Research Center, Covington, Louisiana, USA
| | - Deepak Kaushal
- Southwest National Primate Research Center, Texas Biomedical Research Institute, San Antonio, Texas, USA
| | - Nadia Golden
- Infectious Disease Aerobiology, Division of Microbiology, Tulane National Primate Research Center, Covington, Louisiana, USA
| | - Breeanna Threeton
- Infectious Disease Aerobiology, Division of Microbiology, Tulane National Primate Research Center, Covington, Louisiana, USA
| | - Stephanie Z. Killeen
- Infectious Disease Aerobiology, Division of Microbiology, Tulane National Primate Research Center, Covington, Louisiana, USA
| | - Philip J. Kuehl
- Lovelace Biomedical Research Institute, Albuquerque, New Mexico, USA
| | - Chad J. Roy
- Infectious Disease Aerobiology, Division of Microbiology, Tulane National Primate Research Center, Covington, Louisiana, USA.,Department of Microbiology and Immunology, Tulane School of Medicine, New Orleans, Louisiana, USA.,Address correspondence to: Chad J. Roy, PhD, Infectious Disease Aerobiology, Division of Microbiology, Tulane National Primate Research Center, 18703 Three Rivers Road, Covington, LA 70433, USA
| |
Collapse
|
9
|
Saldana-Morales FB, Kim DV, Tsai MT, Diehl GE. Healthy Intestinal Function Relies on Coordinated Enteric Nervous System, Immune System, and Epithelium Responses. Gut Microbes 2022; 13:1-14. [PMID: 33929291 PMCID: PMC8096330 DOI: 10.1080/19490976.2021.1916376] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
During both health and disease, a coordinated response between the epithelium, immune system, and enteric nervous system is required for proper intestinal function. While each system responds to a number of common stimuli, their coordinated responses support digestion as well as responses and recovery following injury or pathogenic infections. In this review, we discuss how individual responses to common signals work together to support these critical functions.
Collapse
Affiliation(s)
- Fatima B. Saldana-Morales
- Graduate School of Biomedical Sciences, Baylor College of Medicine, HoustonTXUSA,Immunology Program of the Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NYUSA
| | - Dasom V. Kim
- Immunology Program of the Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NYUSA,Immunology and Microbial Pathogenesis Program, Weill Cornell Medical College, Cornell University, New York, NY, USA
| | - Ming-Ting Tsai
- Graduate School of Biomedical Sciences, Baylor College of Medicine, HoustonTXUSA,Immunology Program of the Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NYUSA
| | - Gretchen E. Diehl
- Immunology Program of the Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NYUSA,Immunology and Microbial Pathogenesis Program, Weill Cornell Medical College, Cornell University, New York, NY, USA,CONTACT Gretchen E. Diehl Immunology Program of the Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY10021, USA. Immunology and Microbial Pathogenesis Program, Weill Cornell Medical College, Cornell University, New York, NY, USA
| |
Collapse
|
10
|
Baliashvili D, Gandhi NR, Kim S, Hughes M, Mave V, Mendoza-Ticona A, Gonzales P, Narunsky K, Selvamuthu P, Badal-Faesen S, Upton C, Naini L, Smith E, Gupta A, Churchyard G, Swindells S, Hesseling A, Shah NS. Resistance to Mycobacterium tuberculosis Infection Among Household Contacts: A Multinational Study. Clin Infect Dis 2021; 73:1037-1045. [PMID: 33772550 PMCID: PMC8442792 DOI: 10.1093/cid/ciab269] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Some contacts of patients with tuberculosis remain negative on tests for tuberculosis infection, despite prolonged exposure, suggesting they might be resistant to Mycobacterium tuberculosis infection. The objective of this multinational study was to estimate the proportion of household contacts resistant to M. tuberculosis (resisters). METHODS We conducted a longitudinal study enrolling index patients enrolled in treatment for pulmonary multidrug- or rifampin-resistant tuberculosis and their household contacts. Contacts were tested for tuberculosis infection with a tuberculin skin test (TST) and interferon-gamma release assay (IGRA) at baseline and after 1 year. Exposure was quantified based on index patients' infectiousness, index patient and household contact interaction, and age. We explored multiple definitions of resistance to tuberculosis infection by varying TST negativity cutoffs (0 vs <5 mm), classification of missing test results, and exposure level. RESULTS In total, 1016 contacts were evaluated from 284 households; 572 contacts aged ≥5 years had TST and longitudinal IGRA results available. And 77 (13%) or 71 (12%) contacts were classified as resisters with a <5 mm or 0 mm TST threshold, respectively. Among 263 highly exposed contacts, 29 (11%) or 26 (10%) were classified as resisters using TST cutoffs of <5 mm and 0 mm, respectively. The prevalence of resisters did not differ substantially by sex, age, human immunodeficiency virus (HIV) coinfection, or comorbid conditions. CONCLUSIONS At least 10% of household contacts can be classified as resistant to tuberculosis infection, depending on the definition used, including those with high exposure. Further studies to understand genetic or immunologic mechanisms underlying the resister phenotype may inform novel strategies for therapeutics and vaccines.
Collapse
Affiliation(s)
| | - Neel R Gandhi
- Emory Rollins School of Public Health, Atlanta, Georgia, USA
- Emory School of Medicine, Atlanta, Georgia, USA
| | - Soyeon Kim
- Frontier Science Foundation, Brookline, Massachusetts, USA
| | - Michael Hughes
- Harvard T.H. Chan School of Public Health, Boston, Massachusetts, USA
| | - Vidya Mave
- Byramjee Jeejeebhoy Government Medical College-Johns Hopkins University Clinical Research Site, Pune, Maharashtra, India
| | | | | | | | - Poongulali Selvamuthu
- Chennai Antiviral Research and Treatment (CART) Clinical Research Site, Infectious Diseases Medical Center, Voluntary Health Services, Chennai, India
| | - Sharlaa Badal-Faesen
- Clinical HIV Research Unit, Department of Internal Medicine, School of Clinical Medicine, Faculty of Health Sciences, University of Witwatersrand, Johannesburg, South Africa
| | - Caryn Upton
- TASK Applied Science, Cape Town, South Africa
| | - Linda Naini
- Social and Scientific Systems, Inc., Silver Spring, Maryland, USA
| | | | - Amita Gupta
- Johns Hopkins University, Department of Medicine, Baltimore, Maryland, USA
| | - Gavin Churchyard
- Aurum Institute, Parktown, South Africa
- School of Public Health, University of Witwatersrand, Johannesburg, South Africa
| | | | - Anneke Hesseling
- Desmond Tutu TB Centre, Stellenbosch University, Tygerberg, South Africa
| | - N Sarita Shah
- Emory Rollins School of Public Health, Atlanta, Georgia, USA
- Emory School of Medicine, Atlanta, Georgia, USA
| |
Collapse
|
11
|
Ruhl CR, Pasko BL, Khan HS, Kindt LM, Stamm CE, Franco LH, Hsia CC, Zhou M, Davis CR, Qin T, Gautron L, Burton MD, Mejia GL, Naik DK, Dussor G, Price TJ, Shiloh MU. Mycobacterium tuberculosis Sulfolipid-1 Activates Nociceptive Neurons and Induces Cough. Cell 2020; 181:293-305.e11. [PMID: 32142653 PMCID: PMC7102531 DOI: 10.1016/j.cell.2020.02.026] [Citation(s) in RCA: 77] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 01/13/2020] [Accepted: 02/10/2020] [Indexed: 12/11/2022]
Abstract
Pulmonary tuberculosis, a disease caused by Mycobacterium tuberculosis (Mtb), manifests with a persistent cough as both a primary symptom and mechanism of transmission. The cough reflex can be triggered by nociceptive neurons innervating the lungs, and some bacteria produce neuron-targeting molecules. However, how pulmonary Mtb infection causes cough remains undefined, and whether Mtb produces a neuron-activating, cough-inducing molecule is unknown. Here, we show that an Mtb organic extract activates nociceptive neurons in vitro and identify the Mtb glycolipid sulfolipid-1 (SL-1) as the nociceptive molecule. Mtb organic extracts from mutants lacking SL-1 synthesis cannot activate neurons in vitro or induce cough in a guinea pig model. Finally, Mtb-infected guinea pigs cough in a manner dependent on SL-1 synthesis. Thus, we demonstrate a heretofore unknown molecular mechanism for cough induction by a virulent human pathogen via its production of a complex lipid.
Collapse
Affiliation(s)
- Cody R Ruhl
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Breanna L Pasko
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Haaris S Khan
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Lexy M Kindt
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Chelsea E Stamm
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Luis H Franco
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Connie C Hsia
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Min Zhou
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Colton R Davis
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Tian Qin
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Laurent Gautron
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Center for Hypothalamic Research, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Michael D Burton
- School of Behavioral and Brain Sciences, University of Texas at Dallas, Richardson, TX 75080, USA; Center for Advanced Pain Studies, University of Texas at Dallas, Richardson, TX 75080, USA
| | - Galo L Mejia
- School of Behavioral and Brain Sciences, University of Texas at Dallas, Richardson, TX 75080, USA; Center for Advanced Pain Studies, University of Texas at Dallas, Richardson, TX 75080, USA
| | - Dhananjay K Naik
- School of Behavioral and Brain Sciences, University of Texas at Dallas, Richardson, TX 75080, USA; Center for Advanced Pain Studies, University of Texas at Dallas, Richardson, TX 75080, USA
| | - Gregory Dussor
- School of Behavioral and Brain Sciences, University of Texas at Dallas, Richardson, TX 75080, USA; Center for Advanced Pain Studies, University of Texas at Dallas, Richardson, TX 75080, USA
| | - Theodore J Price
- School of Behavioral and Brain Sciences, University of Texas at Dallas, Richardson, TX 75080, USA; Center for Advanced Pain Studies, University of Texas at Dallas, Richardson, TX 75080, USA
| | - Michael U Shiloh
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
| |
Collapse
|
12
|
Martinez L, Castellanos ME, Hallowell BD, Whalen CC. Innovative Methods to Manage, Detect, and Prevent Tuberculosis. Am J Respir Crit Care Med 2019; 195:530-532. [PMID: 27911589 DOI: 10.1164/rccm.201608-1657rr] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Affiliation(s)
- Leonardo Martinez
- 1 Department of Epidemiology and Biostatistics and.,2 Institute of Global Health, College of Public Health, University of Georgia, Athens, Georgia
| | - María Eugenia Castellanos
- 1 Department of Epidemiology and Biostatistics and.,2 Institute of Global Health, College of Public Health, University of Georgia, Athens, Georgia
| | - Benjamin D Hallowell
- 1 Department of Epidemiology and Biostatistics and.,2 Institute of Global Health, College of Public Health, University of Georgia, Athens, Georgia
| | - Christopher C Whalen
- 1 Department of Epidemiology and Biostatistics and.,2 Institute of Global Health, College of Public Health, University of Georgia, Athens, Georgia
| |
Collapse
|
13
|
Doroshenko A, Pepperell CS, Heffernan C, Egedahl ML, Mortimer TD, Smith TM, Bussan HE, Tyrrell GJ, Long R. Epidemiological and genomic determinants of tuberculosis outbreaks in First Nations communities in Canada. BMC Med 2018; 16:128. [PMID: 30086755 PMCID: PMC6081810 DOI: 10.1186/s12916-018-1112-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Accepted: 06/27/2018] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND In Canada, tuberculosis disproportionately affects foreign-born and First Nations populations. Within First Nations' peoples, a high proportion of cases occur in association with outbreaks. Tuberculosis transmission in the context of outbreaks is thought to result from the convergence of several factors including characteristics of the cases, contacts, the environment, and the pathogen. METHODS We examined the epidemiological and genomic determinants of two well-characterized tuberculosis outbreaks attributed to two super-spreaders among First Nations in the province of Alberta. These outbreaks were associated with two distinct DNA fingerprints (restriction fragment-length polymorphisms or RFLPs 0.0142 and 0.0728). We compared outbreak isolates with endemic isolates not spatio-temporarily linked to outbreak cases. We extracted epidemiological variables pertaining to tuberculosis cases and contacts from individual public health records and the provincial tuberculosis registry. We conducted group analyses using parametric and non-parametric statistical tests. We carried out whole-genome sequencing and bioinformatic analysis using validated protocols. RESULTS We observed differences between outbreak and endemic groups in the mean number of total and child-aged contacts and the number of contacts with new positive and converted tuberculin skin tests in all group comparisons (p < 0.05). Differences were also detected in the proportion of cases with cavitation on a chest radiograph and the mean number of close contacts in selected group comparisons (p < 0.02). A phylogenetic network analysis of whole-genome sequencing data indicated that most outbreak and endemic strains were closely related to the source case for the 0.0142 fingerprint. For the 0.0728 fingerprint, the source case haplotype was circulating among endemic cases prior to the outbreak. Genetic and temporal distances were not correlated for either RFLP 0.0142 (r2 = - 0.05) or RFLP 0.0728 (r2 = 0.09) when all isolates were analyzed. CONCLUSIONS We found no evidence that endemic strains acquired mutations resulting in their emergence in outbreak form. We conclude that the propagation of these outbreaks was likely driven by the combination of characteristics of the source cases, contacts, and the environment. The role of whole-genome sequencing in understanding mycobacterial evolution and in assisting public health authorities in conducting contact investigations and managing outbreaks is important and expected to grow in the future.
Collapse
Affiliation(s)
- Alexander Doroshenko
- Division of Preventive Medicine, Department of Medicine, Faculty of Medicine and Dentistry and School of Public Health, University of Alberta, Edmonton, Canada.
| | - Caitlin S Pepperell
- Departments of Medicine (Infectious Diseases) and Medical Microbiology & Immunology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, USA
| | - Courtney Heffernan
- Department of Medicine, Faculty of Medicine and Dentistry and TB Program Evaluation and Research Unit, University of Alberta, Edmonton, Canada
| | - Mary Lou Egedahl
- Department of Medicine, Faculty of Medicine and Dentistry and TB Program Evaluation and Research Unit, University of Alberta, Edmonton, Canada
| | - Tatum D Mortimer
- Departments of Medicine (Infectious Diseases) and Medical Microbiology & Immunology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, USA
| | - Tracy M Smith
- Departments of Medicine (Infectious Diseases) and Medical Microbiology & Immunology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, USA
| | - Hailey E Bussan
- Departments of Medicine (Infectious Diseases) and Medical Microbiology & Immunology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, USA
| | - Gregory J Tyrrell
- Department of Laboratory Medicine and Pathology, University of Alberta, Provincial Laboratory for Public Health, Alberta Health Services, Edmonton, Canada
| | - Richard Long
- Department of Medicine, Faculty of Medicine and Dentistry and TB Program Evaluation and Research Unit, University of Alberta, Edmonton, Canada
| |
Collapse
|
14
|
Doan TN, Eisen DP, Rose MT, Slack A, Stearnes G, McBryde ES. Interferon-gamma release assay for the diagnosis of latent tuberculosis infection: A latent-class analysis. PLoS One 2017; 12:e0188631. [PMID: 29182688 PMCID: PMC5705142 DOI: 10.1371/journal.pone.0188631] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Accepted: 11/11/2017] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Accurate diagnosis and subsequent treatment of latent tuberculosis infection (LTBI) is essential for TB elimination. However, the absence of a gold standard test for diagnosing LTBI makes assessment of the true prevalence of LTBI and the accuracy of diagnostic tests challenging. Bayesian latent class models can be used to make inferences about disease prevalence and the sensitivity and specificity of diagnostic tests using data on the concordance between tests. We performed the largest meta-analysis to date aiming to evaluate the performance of tuberculin skin test (TST) and interferon-gamma release assays (IGRAs) for LTBI diagnosis in various patient populations using Bayesian latent class modelling. METHODS Systematic search of PubMeb, Embase and African Index Medicus was conducted without date and language restrictions on September 11, 2017 to identify studies that compared the performance of TST and IGRAs for LTBI diagnosis. Two IGRA methods were considered: QuantiFERON-TB Gold In Tube (QFT-GIT) and T-SPOT.TB. Studies were included if they reported 2x2 agreement data between TST and QFT-GIT or T-SPOT.TB. A Bayesian latent class model was developed to estimate the sensitivity and specificity of TST and IGRAs in various populations, including immune-competent adults, immune-compromised adults and children. A TST cut-off value of 10 mm was used for immune-competent subjects and 5 mm for immune-compromised individuals. FINDINGS A total of 157 studies were included in the analysis. In immune-competent adults, the sensitivity of TST and QFT-GIT were estimated to be 84% (95% credible interval [CrI] 82-85%) and 52% (50-53%), respectively. The specificity of QFT-GIT was 97% (96-97%) in non-BCG-vaccinated and 93% (92-94%) in BCG-vaccinated immune-competent adults. The estimated figures for TST were 100% (99-100%) and 79% (76-82%), respectively. T-SPOT.TB has comparable specificity (97% for both tests) and better sensitivity (68% versus 52%) than QFT-GIT in immune-competent adults. In immune-compromised adults, both TST and QFT-GIT display low sensitivity but high specificity. QFT-GIT and TST are equally specific (98% for both tests) in non-BCG-vaccinated children; however, QFT-GIT is more specific than TST (98% versus 82%) in BCG-vaccinated group. TST is more sensitive than QFT-GIT (82% versus 73%) in children. CONCLUSIONS This study is the first to assess the utility of TST and IGRAs for LTBI diagnosis in different population groups using all available data with Bayesian latent class modelling. Our results challenge the current beliefs about the performance of LTBI screening tests, and have important implications for LTBI screening policy and practice. We estimated that the performance of IGRAs is not as reliable as previously measured in the general population. However, IGRAs are not or minimally affected by BCG and should be the preferred tests in this setting. Adoption of IGRAs in settings where BCG is widely administered will allow for a more accurate identification and treatment of LTBI.
Collapse
Affiliation(s)
- Tan N. Doan
- Department of Medicine at The Royal Melbourne Hospital, University of Melbourne, Melbourne, Victoria, Australia
- Australian Institute of Tropical Health and Medicine, James Cook University, Townsville, Queensland, Australia
- Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
- * E-mail:
| | - Damon P. Eisen
- College of Medicine and Dentistry, James Cook University, Townsville, Queensland, Australia
- Townsville Hospital and Health Service, Townsville, Queensland, Australia
| | - Morgan T. Rose
- Department of Infectious Diseases, Alfred Health, Melbourne, Victoria, Australia
| | - Andrew Slack
- Townsville Hospital and Health Service, Townsville, Queensland, Australia
| | - Grace Stearnes
- Townsville Hospital and Health Service, Townsville, Queensland, Australia
| | - Emma S. McBryde
- Department of Medicine at The Royal Melbourne Hospital, University of Melbourne, Melbourne, Victoria, Australia
- Australian Institute of Tropical Health and Medicine, James Cook University, Townsville, Queensland, Australia
| |
Collapse
|
15
|
Jones-López EC, Acuña-Villaorduña C, Fregona G, Marques-Rodrigues P, White LF, Hadad DJ, Dutra-Molina LP, Vinhas S, McIntosh AI, Gaeddert M, Ribeiro-Rodrigues R, Salgame P, Palaci M, Alland D, Ellner JJ, Dietze R. Incident Mycobacterium tuberculosis infection in household contacts of infectious tuberculosis patients in Brazil. BMC Infect Dis 2017; 17:576. [PMID: 28821234 PMCID: PMC5563014 DOI: 10.1186/s12879-017-2675-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Accepted: 08/08/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND In household contact investigations of tuberculosis (TB), a second tuberculin skin test (TST) obtained several weeks after a first negative result consistently identifies individuals that undergo TST conversion. It remains unclear whether this delay in M. tuberculosis infection is related to differences in the infectious exposure, TST boosting, partial host resistance, or some other factor. METHODS We conducted a household contact study Vitória, Brazil. Between 2008 and 2013, we identified culture-positive pulmonary TB patients and evaluated their household contacts with both a TST and interferon gamma release assay (IGRA), and identified TST converters at 8-12 weeks post study enrollment. Contacts were classified as TST-positive (≥10 mm) at baseline, TST converters, or persistently TST-negative. We compared TST converters to TST-positive and to TST-negative contacts separately, using generalized estimating equations. RESULTS We enrolled 160 index patients and 838 contacts; 523 (62.4%) were TST+, 62 (7.4%) TST converters, and 253 (30.2%) TST-. TST converters were frequently IGRA- at 8-12 weeks. In adjusted analyses, characteristics distinguishing TST converters from TST+ contacts (no contact with another TB patient and residence ownership) were different than those differentiating them from TST- contacts (stronger cough in index patient and contact BCG scar). CONCLUSIONS The individual risk and timing of M. tuberculosis infection within households is variable and dependent on index patient, contact and environmental factors within the household, and the surrounding community. Our findings suggest a threshold effect in the risk of infection in humans.
Collapse
Affiliation(s)
- Edward C Jones-López
- Section of Infectious Diseases, Department of Medicine, Boston Medical Center and Boston University School of Medicine, 650 Albany Street, Room 605, Boston, MA, 02118, USA.
| | - Carlos Acuña-Villaorduña
- Section of Infectious Diseases, Department of Medicine, Boston Medical Center and Boston University School of Medicine, 650 Albany Street, Room 605, Boston, MA, 02118, USA.
| | - Geisa Fregona
- Núcleo de Doenças Infecciosas, Universidade Federal do Espírito Santo (UFES), Vitória, Brazil
| | | | - Laura F White
- Department of Biostatistics, Boston University School of Public Health, Boston, MA, USA
| | - David Jamil Hadad
- Núcleo de Doenças Infecciosas, Universidade Federal do Espírito Santo (UFES), Vitória, Brazil
| | | | - Solange Vinhas
- Mycobacteriology Laboratory, Núcleo de Doenças Infecciosas, UFES, Vitória, Brazil
| | - Avery I McIntosh
- Department of Biostatistics, Boston University School of Public Health, Boston, MA, USA
| | - Mary Gaeddert
- Section of Infectious Diseases, Department of Medicine, Boston Medical Center and Boston University School of Medicine, 650 Albany Street, Room 605, Boston, MA, 02118, USA
| | | | - Padmini Salgame
- Division of Infectious Diseases, Department of Medicine, New Jersey Medical School- Rutgers University, Newark, NJ, USA
| | - Moises Palaci
- Mycobacteriology Laboratory, Núcleo de Doenças Infecciosas, UFES, Vitória, Brazil
| | - David Alland
- Division of Infectious Diseases, Department of Medicine, New Jersey Medical School- Rutgers University, Newark, NJ, USA
| | - Jerrold J Ellner
- Section of Infectious Diseases, Department of Medicine, Boston Medical Center and Boston University School of Medicine, 650 Albany Street, Room 605, Boston, MA, 02118, USA
| | - Reynaldo Dietze
- Núcleo de Doenças Infecciosas, Universidade Federal do Espírito Santo (UFES), Vitória, Brazil
| |
Collapse
|
16
|
Jones-López EC, Acuña-Villaorduña C, Ssebidandi M, Gaeddert M, Kubiak RW, Ayakaka I, White LF, Joloba M, Okwera A, Fennelly KP. Cough Aerosols of Mycobacterium tuberculosis in the Prediction of Incident Tuberculosis Disease in Household Contacts. Clin Infect Dis 2016; 63:10-20. [PMID: 27025837 DOI: 10.1093/cid/ciw199] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Accepted: 03/18/2016] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Tuberculosis disease develops in only 5%-10% of humans infected with Mycobacterium tuberculosis The mechanisms underlying this variability remain poorly understood. We recently demonstrated that colony-forming units of M. tuberculosis in cough-generated aerosols are a better predictor of infection than the standard sputum acid-fast bacilli smear. We hypothesized that cough aerosol cultures may also predict progression to tuberculosis disease in contacts. METHODS We conducted a retrospective cohort study of 85 patients with smear-positive tuberculosis and their 369 household contacts in Kampala, Uganda. Index case patients underwent a standard evaluation, and we cultured M. tuberculosis from cough aerosols. Contacts underwent a standard evaluation at enrollment, and they were later traced to determine their tuberculosis status. RESULTS During a median follow-up of 3.9 years, 8 (2%) of the contacts developed tuberculosis disease. In unadjusted and adjusted analyses, incident tuberculosis disease in contacts was associated with sputum Mycobacterial Growth Indicator Tube culture (odds ratio, 8.2; 95% confidence interval, 1.1-59.2; P = .04), exposure to a high-aerosol tuberculosis case patient (6.0, 1.4-25.2; P = .01), and marginally, human immunodeficiency virus in the contact (6.11; 0.89-41.7; P = .07). We present data demonstrating that sputum and aerosol specimens measure 2 related but different phenomena. CONCLUSIONS We found an increased risk of tuberculosis progression among contacts of high-aerosol case patients. The hypothesis that a larger infectious inoculum, represented by high aerosol production, determines the risk of disease progression deserves evaluation in future prospective studies.
Collapse
Affiliation(s)
- Edward C Jones-López
- Section of Infectious Diseases, Department of Medicine, Boston Medical Center and Boston University School of Medicine Makerere University-Boston Medical Center Research Collaboration
| | - Carlos Acuña-Villaorduña
- Section of Infectious Diseases, Department of Medicine, Boston Medical Center and Boston University School of Medicine
| | | | - Mary Gaeddert
- Section of Infectious Diseases, Department of Medicine, Boston Medical Center and Boston University School of Medicine
| | - Rachel W Kubiak
- Section of Infectious Diseases, Department of Medicine, Boston Medical Center and Boston University School of Medicine
| | - Irene Ayakaka
- Makerere University-Boston Medical Center Research Collaboration
| | - Laura F White
- Department of Biostatistics, Boston University School of Public Health, Massachusetts
| | - Moses Joloba
- Department of Microbiology, Makerere University College of Health Sciences
| | - Alphonse Okwera
- Makerere University-Boston Medical Center Research Collaboration Mulago Hospital Tuberculosis Clinic, Mulago Hospital, Kampala, Uganda
| | - Kevin P Fennelly
- Pulmonary Clinical Medicine Section, Cardiovascular and Pulmonary Branch, Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland
| |
Collapse
|