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Njagi LN, Kaguthi G, Mecha JO, Hawn TR, Nduba V. Attenuated tuberculin skin test responses associated with Mycobacterium intracellulare sputum colonization in an adolescent TB prevalence survey in Western Kenya. Tuberculosis (Edinb) 2024; 147:102514. [PMID: 38723342 PMCID: PMC11168861 DOI: 10.1016/j.tube.2024.102514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Revised: 04/16/2024] [Accepted: 05/03/2024] [Indexed: 05/26/2024]
Abstract
INTRODUCTION Exposure to Non-tuberculous Mycobacteria (NTM) varies regionally and may partly explain the disparate outcomes of BCG vaccination and tuberculosis (TB) susceptibility. METHODS We examined NTM sputum colonization, associations with clinical characteristics, and tuberculin skin test (TST) responses in an adolescent TB prevalence survey. RESULTS Among 5004 adolescents screened, 2281 (45.5 %) were evaluated further. TB and NTM prevalence rates were 0.3 % and 8.0 %, respectively. Among 418 NTM isolates, 103 were unidentifiable, and 315 (75 %) comprised 15 species, the most frequent being M. intracellulare (MAC) (108, 26 %), M. scrofulaceum (96, 23 %) and M. fortuitum (51, 12 %). "NTM colonized" adolescents had less frequent chronic cough and night sweats (adjusted odds ratio [aOR] 0.62, 95 % confidence interval [CI] 0.44-0.87and aOR 0.61, CI 0.42-0.89 respectively), and lower TST induration (median 11 mm (interquartile range [IQR] 0-16) vs 13 mm (IQR 6-17; p = 0.006)) when compared to "NTM not colonized" participants. MAC, but not M. scrofulaceum or M. fortuitum, was associated with decreased TST induration (median 7.5 mm (IQR 0-15) vs 13 mm (IQR 6-17) among "MAC colonized" vs "not colonized", p = 0.001). CONCLUSION We observed high NTM prevalence rates with species-specific associations with TST induration, consistent with a model of species-dependent heterologous immunity among mycobacteria.
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Affiliation(s)
- Lilian N Njagi
- Kenya Medical Research Institute, Centre for Respiratory Diseases Research (CRDR), PO Box 47855-00100, Nairobi, Kenya.
| | - Grace Kaguthi
- Kenya Medical Research Institute, Centre for Respiratory Diseases Research (CRDR), PO Box 47855-00100, Nairobi, Kenya.
| | - Jared O Mecha
- Department of Clinical Medicine and Therapeutics, Faculty of Health Sciences, University of Nairobi School of Medicine, PO Box 19676 - 00202, Nairobi, Kenya.
| | - Thomas R Hawn
- Department of Medicine, University of Washington, Seattle, WA, 98195, United States.
| | - Videlis Nduba
- Kenya Medical Research Institute, Centre for Respiratory Diseases Research (CRDR), PO Box 47855-00100, Nairobi, Kenya.
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Song Z, Chen L, Sun S, Yang G, Yu G. Unveiling the airborne microbial menace: Novel insights into pathogenic bacteria and fungi in bioaerosols from nursery schools to universities. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 929:172694. [PMID: 38670386 DOI: 10.1016/j.scitotenv.2024.172694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Revised: 04/07/2024] [Accepted: 04/21/2024] [Indexed: 04/28/2024]
Abstract
Bacterial and fungal aerosol pollution is widespread in indoor school environments, and poses potential health risks to students and staff. Understanding the distribution and diversity of microbial communities within aerosols is crucial to mitigate their adverse effects. Existing knowledge regarding the composition of bacterial and fungal aerosols, particularly the presence of potential pathogenic microorganisms in fine particulate matter (PM2.5) from nursery schools to universities, is limited. To bridge this knowledge gap, in the present study, we collected PM2.5 samples from five types of schools (i.e., nursery schools, primary schools, junior schools, and high schools and universities) in China. We used advanced single-molecule real-time sequencing to analyze the species-level diversity of bacterial and fungal components in PM2.5 samples based on 16S and ITS ribosomal genes, respectively. We found significant differences in microbial diversity and community composition among the samples obtained from different educational institutions and pollution levels. In particularly, junior schools exhibited higher PM2.5 concentrations (62.2-86.6 μg/m3) than other schools (14.4-48.4 μg/m3). Moreover, microbial variations in PM2.5 samples were associated with institution type. Notably, the prevailing pathogenic microorganisms included Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus haemolyticus, Streptococcus pneumoniae, and Schizophyllum commune, all of which were identified as Class II Pathogenic Microorganisms in school settings. Four potentially novel strains of S. commune were identified in PM2.5 samples collected from the university; the four strains showed 92.4 %-94.1 % ITS sequence similarity to known Schizophyllum isolates. To the best of our knowledge, this is the first study to explore bacterial and fungal diversity within PM2.5 samples from nursery schools to universities. Overall, these findings contribute to the existing knowledge of school environmental microbiology to ensure the health and safety of students and staff and impacting public health.
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Affiliation(s)
- Zhicheng Song
- College of Life Sciences, Shandong Normal University, Jinan 250014, China
| | - Lei Chen
- College of Life Sciences, Shandong Normal University, Jinan 250014, China
| | - Shuwei Sun
- Jinan Licheng No.2 High School, Jinan 250109, China
| | - Guiwen Yang
- College of Life Sciences, Shandong Normal University, Jinan 250014, China
| | - Guanliu Yu
- College of Life Sciences, Shandong Normal University, Jinan 250014, China.
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Rickman HM, Phiri MD, Feasey HRA, Mbale H, Nliwasa M, Semphere R, Chagaluka G, Fielding K, Mwandumba HC, Horton KC, Nightingale ES, Henrion MYR, Mbendera K, Mpunga JA, Corbett EL, MacPherson P. Tuberculosis Immunoreactivity Surveillance in Malawi (Timasamala)-A protocol for a cross-sectional Mycobacterium tuberculosis immunoreactivity survey in Blantyre, Malawi. PLoS One 2024; 19:e0291215. [PMID: 38787869 PMCID: PMC11125513 DOI: 10.1371/journal.pone.0291215] [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: 09/04/2023] [Accepted: 02/28/2024] [Indexed: 05/26/2024] Open
Abstract
Tuberculosis (TB) transmission and prevalence are dynamic over time, and heterogeneous within populations. Public health programmes therefore require up-to-date, accurate epidemiological data to appropriately allocate resources, target interventions, and track progress towards End TB goals. Current methods of TB surveillance often rely on case notifications, which are biased by access to healthcare, and TB disease prevalence surveys, which are highly resource-intensive, requiring many tens of thousands of people to be tested to identify high-risk groups or capture trends. Surveys of "latent TB infection", or immunoreactivity to Mycobacterium tuberculosis (Mtb), using tests such as interferon-gamma release assays (IGRAs) could provide a way to identify TB transmission hotspots, supplementing information from disease notifications, and with greater spatial and temporal resolution than is possible to achieve in disease prevalence surveys. This cross-sectional survey will investigate the prevalence of Mtb immunoreactivity amongst young children, adolescents and adults in Blantyre, Malawi, a high HIV-prevalence city in southern Africa. Through this study we will estimate the annual risk of TB infection (ARTI) in Blantyre and explore individual- and area-level risk factors for infection, as well as investigating geospatial heterogeneity of Mtb infection (and its determinants), and comparing these to the distribution of TB disease case-notifications. We will also evaluate novel diagnostics for Mtb infection (QIAreach QFT) and sampling methodologies (convenience sampling in healthcare settings and community sampling based on satellite imagery), which may increase the feasibility of measuring Mtb infection at large scale. The overall aim is to provide high-resolution epidemiological data and provide new insights into methodologies which may be used by TB programmes globally.
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Affiliation(s)
- Hannah M. Rickman
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, United Kingdom
- Malawi Liverpool Wellcome Programme, Blantyre, Malawi
| | - Mphatso D. Phiri
- Malawi Liverpool Wellcome Programme, Blantyre, Malawi
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Helena R. A. Feasey
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, United Kingdom
- Malawi Liverpool Wellcome Programme, Blantyre, Malawi
| | - Hannah Mbale
- Malawi Liverpool Wellcome Programme, Blantyre, Malawi
| | - Marriott Nliwasa
- Helse Nord TB Initiative, Kamuzu University of Health Sciences, Blantyre, Malawi
| | - Robina Semphere
- Helse Nord TB Initiative, Kamuzu University of Health Sciences, Blantyre, Malawi
- School of Health & Wellbeing, University of Glasgow, Glasgow, United Kingdom
| | - George Chagaluka
- Department of Paediatrics, Queen Elizabeth Central Hospital, Blantyre, Malawi
| | - Katherine Fielding
- Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Henry C. Mwandumba
- Malawi Liverpool Wellcome Programme, Blantyre, Malawi
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Katherine C. Horton
- Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Emily S. Nightingale
- Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Marc Y. R. Henrion
- Malawi Liverpool Wellcome Programme, Blantyre, Malawi
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Kuzani Mbendera
- Malawi National Tuberculosis and Leprosy Control Programme, Lilongwe, Malawi
| | - James A. Mpunga
- Malawi National Tuberculosis and Leprosy Control Programme, Lilongwe, Malawi
| | - Elizabeth L. Corbett
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, United Kingdom
- Malawi Liverpool Wellcome Programme, Blantyre, Malawi
| | - Peter MacPherson
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, United Kingdom
- Malawi Liverpool Wellcome Programme, Blantyre, Malawi
- School of Health & Wellbeing, University of Glasgow, Glasgow, United Kingdom
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Serial T-SPOT.TB responses in Tanzanian adolescents: Transient, persistent and irregular conversions. PLoS One 2022; 17:e0268685. [PMID: 35749397 PMCID: PMC9231806 DOI: 10.1371/journal.pone.0268685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2021] [Accepted: 05/04/2022] [Indexed: 11/29/2022] Open
Abstract
Background Prospective studies of interferon-gamma release assays (IGRA) on healthy subjects in tuberculosis-endemic regions have not examined the long-term variability of serial assays. This issue is relevant to the interpretation of tuberculosis (TB) vaccine trials based on prevention of infection. Methods T-SPOT.TB assays were performed manually on healthy adolescents during a tuberculosis vaccine trial in Tanzania at 5 intervals over 3 years. Assay results were defined as negative, positive, borderline or invalid. Subsequently, microtiter plates were analyzed by an automated reader to obtain quantitative counts of spot forming cells (SFCs) for the present analysis. Results 3387 T-SPOT.TB samples were analyzed from 928 adolescents; manual and automated assay results were 97% concordant. Based on the quantitative results 143 (15%) participants were prevalent IGRA-positives at baseline, were ineligible for further study. Among the remaining IGRA-negative participants, the annual rate of IGRA conversion was 2·9%. Among 43 IGRA converters with repeat assays 12 (28%) were persistent converters, 16 (37%) were transient converters, and 15 (35%) comprised a new category defined as irregular converters (≥2 different subsequent results). ESAT-6 and CFP-10 responses were higher in prevalent than incident positives: 53 vs 36 for CFP-10 (p < 0·007); 44 vs 34 for ESAT-6 (p = 0·12). Conclusions Definitions of IGRA conversion, reversion, and persistence depend critically on the frequency of testing. Multiple shifts in categories among adolescents in a TB-endemic country may represent multiple infections, variable host responses in subclinical infection, or assay variation. These findings should to be considered in the design and interpretation of TB vaccine trials based on prevention of infection. Household contact studies could determine whether even transient IGRA conversion might represent exposure to an active case of M. tuberculosis disease.
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Laycock KM, Enane LA, Steenhoff AP. Tuberculosis in Adolescents and Young Adults: Emerging Data on TB Transmission and Prevention among Vulnerable Young People. Trop Med Infect Dis 2021; 6:148. [PMID: 34449722 PMCID: PMC8396328 DOI: 10.3390/tropicalmed6030148] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 07/30/2021] [Accepted: 07/31/2021] [Indexed: 02/01/2023] Open
Abstract
Adolescents and young adults (AYA, ages 10-24 years) comprise a uniquely important but understudied population in global efforts to end tuberculosis (TB), the leading infectious cause of death by a single agent worldwide prior to the COVID-19 pandemic. While TB prevention and care strategies often overlook AYA by grouping them with either children or adults, AYA have particular physiologic, developmental, and social characteristics that require dedicated approaches. This review describes current evidence on the prevention and control of TB among AYA, including approaches to TB screening, dynamics of TB transmission among AYA, and management challenges within the context of unique developmental needs. Challenges are considered for vulnerable groups of AYA such as migrants and refugees; AYA experiencing homelessness, incarceration, or substance use; and AYA living with HIV. We outline areas for needed research and implementation strategies to address TB among AYA globally.
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Affiliation(s)
- Katherine M. Laycock
- Division of Infectious Diseases, Department of Pediatrics, Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA;
| | - Leslie A. Enane
- The Ryan White Center for Pediatric Infectious Disease and Global Health, Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN 46202, USA;
| | - Andrew P. Steenhoff
- Division of Infectious Diseases, Department of Pediatrics, Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA;
- Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Global Health Center, Children’s Hospital of Philadelphia, Philadelphia, PA 19146, USA
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Jeremiah K, Lyimo E, Ritz C, PrayGod G, Rutkowski KT, Korsholm KS, Ruhwald M, Tait D, Grewal HMS, Faurholt-Jepsen D. Prevalence of Mycobacterium tuberculosis infection as measured by the QuantiFERON-TB Gold assay and ESAT-6 free IGRA among adolescents in Mwanza, Tanzania. PLoS One 2021; 16:e0252808. [PMID: 34097715 PMCID: PMC8183982 DOI: 10.1371/journal.pone.0252808] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Accepted: 05/21/2021] [Indexed: 11/19/2022] Open
Abstract
Background The prevalence of latent tuberculosis infection (LTBI) is vastly higher than that of tuberculosis (TB) disease and this enormous reservoir of individuals with LTBI impacts the global TB control strategy. Adolescents are at greatest risk of TB infection and are thus an ideal target population for a potential effective TB vaccine to be added to the current BCG programme as it could reduce the number of latent infections and consequently the number of adults with TB disease. However, LTBI rates are often unknown for this population. This study aims to estimate the magnitude of LTBI and to determine if Tanzanian adolescents would be a good population for a prevention of TB infection trial. Methods This was a descriptive cross-sectional study that recruited 193 adolescents aged 12 and 16 years from government schools and directly from the community in Mwanza Region, Tanzania. Socio-demographic characteristics were collected for all enrolled participants. Blood was drawn and tested using QuantiFERON-TB Gold In-Tube (QFT-GIT), and Early Secretory Antigenic Target-6–Free Interferon-gamma Release Assay (ESAT-6 free IGRA). Concordance between QFT-GIT and ESAT-6 free IGRA was evaluated using the McNemar’s test. Results Overall estimates of LTBI prevalence were 19.2% [95%CI, 14.1; 25.2] and 18.6% [95%CI, 13.6; 24.6] as measured by QFT-GIT IGRA and ESAT-6 free IGRA, respectively. The 16-year-old cohort had a higher LTBI prevalence (23.7% [95%CI, 16.1; 32.9]) as compared to 12-year-old cohort (14.6% [95%CI, 8.6; 22.7]) as measured by QFT-GIT IGRA. When measured by ESAT-6 Free IGRA, LTBI prevalence was 24.7% (95%CI, 16.9; 34.0) for the 16-year-old cohort and 12.5% (95%CI, 7.0; 20.3) among the 12-year-old cohort. According to both tests the prevalence of TB infection and the corresponding annual risk of tuberculosis infection (ARTI) and force of infection were high and increased with age. Of all enrolled participants, 97.4% had concordant results for QFT-GIT IGRA and ESAT-6 free IGRA (p = 0.65). Conclusions The prevalence of LTBI and the associated ARTI and force of infection among adolescents is high and increases with age in Mwanza Region. There was a high concordance between the QFT-GIT and the novel ESAT-6 free IGRA assays. These findings suggest Mwanza is a promising area to conduct novel TB vaccine research prevention of infection (POI) studies targeting adolescents.
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Affiliation(s)
- Kidola Jeremiah
- Mwanza Research Centre, National Institute for Medical Research, Mwanza, Tanzania
- * E-mail:
| | - Eric Lyimo
- Mwanza Research Centre, National Institute for Medical Research, Mwanza, Tanzania
| | - Christian Ritz
- Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - George PrayGod
- Mwanza Research Centre, National Institute for Medical Research, Mwanza, Tanzania
| | - Kathryn Tucker Rutkowski
- International AIDS Vaccine Initiative (IAVI,), New York City, New York, United States of America
| | - Karen Smith Korsholm
- Department of Infectious Immunology, Centre for Vaccine Research, Statens Serum Institut (SSI), Copenhagen, Denmark
- Department of Vaccine Development, Centre for Vaccine Research, Statens Serum Institut (SSI), Copenhagen, Denmark
| | - Morten Ruhwald
- Department of Infectious Immunology, Centre for Vaccine Research, Statens Serum Institut (SSI), Copenhagen, Denmark
- Department of Vaccine Development, Centre for Vaccine Research, Statens Serum Institut (SSI), Copenhagen, Denmark
- Foundation of Innovative New Diagnostics, Geneva, Switzerland
| | - Dereck Tait
- International AIDS Vaccine Initiative (IAVI) NPC, Cape Town, South Africa
| | - Harleen M. S. Grewal
- Department of Clinical Science, BIDS Group, Faculty of Medicine, University of Bergen, Bergen, Norway
- Department of Microbiology, Haukeland University Hospital, Bergen, Norway
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Aduh U, Ewa AU, Sam-Agudu NA, Urhioke O, Kusimo O, Ugwu C, Fadare OA, Anyaike C. Addressing gaps in adolescent tuberculosis programming and policy in Nigeria from a public health perspective. Int J Adolesc Med Health 2021; 33:41-51. [PMID: 33913304 DOI: 10.1515/ijamh-2020-0293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Accepted: 04/01/2021] [Indexed: 11/15/2022]
Abstract
OBJECTIVES Tuberculosis (TB) is a leading infectious cause of death globally. Of the estimated 10 million people who developed active TB in 2019, 1.8 million (18%) were adolescents and young adults aged 15-24 years. Adolescents have poorer rates of TB screening, treatment initiation and completion compared to adults. Unfortunately, there is relatively less programme, research and policy focus on TB for adolescents aged 10-19 years. This article reviews the scope of health services and the relevant policy landscape for TB case notification and care/treatment, TB/HIV management, and latent TB infection for adolescents in Nigeria. Additionally, it discusses considerations for TB vaccines in this population. CONTENT All Nigeria Federal Ministry of Health policy documents relevant to adolescent health services and TB, and published between 2000 and 2020 underwent narrative review. Findings were reported according to the service areas outlined in the Objectives. SUMMARY AND OUTLOOK Nine policy documents were identified and reviewed. While multiple policies acknowledge the needs of adolescents in public health and specifically in TB programming, these needs are often not addressed in policy, nor in program integration and implementation. The lack of age-specific epidemiologic and clinical outcomes data for adolescents contributes to these policy gaps. Poor outcomes are driven by factors such as HIV co-infection, lack of youth-friendly health services, and stigma and discrimination. Policy guidelines and innovations should include adaptations tailored to adolescent needs. However, these adaptations cannot be developed without robust epidemiological data on adolescents at risk of, and living with TB. Gaps in TB care integration into primary reproductive, maternal-child health and nutrition services should be addressed across multiple policies, and mechanisms for supervision, and monitoring and evaluation of integration be developed to guide comprehensive implementation. Youth-friendly TB services are recommended to improve access to quality care delivered in a patient-centered approach.
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Affiliation(s)
- Ufuoma Aduh
- World Health Organisation, Abuja, Nigeria
- Texila American University, Georgetown, Guyana
| | - Atana Uket Ewa
- Department of Paediatrics, University of Calabar and University of Calabar Teaching Hospital, Calabar, Nigeria
| | - Nadia A Sam-Agudu
- International Research Center of Excellence, Institute of Human Virology Nigeria, Abuja, Nigeria
- Institute of Human Virology and Department of Pediatrics, University of Maryland School of Medicine, Baltimore, USA
| | - Ochuko Urhioke
- National TB and Leprosy Control Programme, Federal Ministry of Health, Abuja, Nigeria
| | | | | | | | - Chukwuma Anyaike
- National TB and Leprosy Control Programme, Federal Ministry of Health, Abuja, Nigeria
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Frigati LJ, Wilkinson KA, le Roux S, Brown K, Ruzive S, Githinji L, Petersen W, Belard S, Cotton MF, Myer L, Zar HJ. Tuberculosis infection and disease in South African adolescents with perinatally acquired HIV on antiretroviral therapy: a cohort study. J Int AIDS Soc 2021; 24:e25671. [PMID: 33719199 PMCID: PMC7957181 DOI: 10.1002/jia2.25671] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 12/22/2020] [Accepted: 01/27/2021] [Indexed: 11/10/2022] Open
Abstract
INTRODUCTION There are limited data on Tuberculosis (TB) in adolescents with perinatally acquired HIV (APHIV). We examined the incidence and determinants of TB infection and disease in the Cape Town Adolescent Antiretroviral Cohort (CTAAC). METHODS Youth between nine and fourteen years on antiretroviral therapy (ART) for more than six months in public sector care, and age-matched HIV-negative adolescents, were enrolled between July 2013 through March 2015 and followed six-monthly. Data were censored on 31 October 2018. Symptom screening, chest radiograph, viral load, CD4 count, QuantiFERON (QFT) and sputum for Xpert MTB/RIF, microscopy, culture and sensitivity were performed annually. TB infection was defined by a QFT of >0.35 IU/mL. TB diagnosis was defined as confirmed (culture or Xpert MTB/RIF positive) or unconfirmed (clinical diagnosis and started on TB treatment). Analyses examined the incidence and determinants of TB infection and disease. RESULTS Overall 496 HIV+ and 103 HIV-negative participants (median age at enrolment 12 years (interquartile range, IQR 10.6 to 13.3) were followed for a median of 3.1 years (IQR 3.0 to 3.4); 50% (298/599) were male. APHIV initiated ART at median age 4.4 years (IQR 2.1 to 7.6). At enrolment, 376/496 (76%) had HIV viral load <40 copies/mL, median CD4 count was 713 cells/mm3 and 179/559 (32%) were QFT+, with no difference by HIV status (APHIV 154/468, 33%; HIV negative 25/91, 27%; p = 0.31). The cumulative QFT+ prevalence was similar (APHIV 225/492, 46%; 95%CI 41% to 50%; HIV negative 44/98, 45%; 95% CI 35% to 55%; p = 0.88). APHIV had a higher incidence of all TB disease than HIV-negative adolescents (2.2/100PY, 95% CI 1.6 to 3.1 vs. 0.3/100PY, 95% CI 0.04 to 2.2; IRR 7.36, 95% CI 1.01 to 53.55). The rate of bacteriologically confirmed TB in APHIV was 1.3/100 PY compared to 0.3/100PY for HIV-negative adolescents, suggesting a fourfold increased risk of developing TB disease in APHIV despite access to ART. In addition, a positive QFT at enrolment was not predictive of TB in this population. CONCLUSIONS High incidence rates of TB disease occur in APHIV despite similar QFT conversion rates to HIV-negative adolescents. Strategies to prevent TB in this vulnerable group must be strengthened.
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Affiliation(s)
- Lisa J Frigati
- Department of Paediatrics and Child HealthUniversity of Cape TownCapeSouth Africa
- Family Center for Research with Ubuntu (FAMCRU)Department of Paediatrics and Child HealthStellenbosch UniversityCape TownSouth Africa
| | - Katalin A Wilkinson
- Wellcome Centre for Infectious Disease Research in AfricaInstitute of Infectious Disease and Molecular MedicineUniversity of Cape TownCape TownSouth Africa
- The Francis Crick InstituteLondonUnited Kingdom
| | - Stanzi le Roux
- Division of Epidemiology and BiostatisticsSchool of Public Health and Family MedicineUniversity of Cape TownCape TownSouth Africa
| | - Karryn Brown
- Division of Epidemiology and BiostatisticsSchool of Public Health and Family MedicineUniversity of Cape TownCape TownSouth Africa
| | - Sheena Ruzive
- Wellcome Centre for Infectious Disease Research in AfricaInstitute of Infectious Disease and Molecular MedicineUniversity of Cape TownCape TownSouth Africa
| | - Leah Githinji
- Department of Paediatrics and Child HealthUniversity of Cape TownCapeSouth Africa
| | - Wonita Petersen
- Department of Paediatrics and Child HealthUniversity of Cape TownCapeSouth Africa
| | - Sabine Belard
- Department of Pediatric Pulmonology, Immunology and Intensive Care MedicineCharité ‐ Universitätsmedizin BerlinBerlinGermany
- Berlin Institute of HealthBerlinGermany
| | - Mark F Cotton
- Family Center for Research with Ubuntu (FAMCRU)Department of Paediatrics and Child HealthStellenbosch UniversityCape TownSouth Africa
| | - Landon Myer
- Division of Epidemiology and BiostatisticsSchool of Public Health and Family MedicineUniversity of Cape TownCape TownSouth Africa
| | - Heather J Zar
- Department of Paediatrics and Child HealthUniversity of Cape TownCapeSouth Africa
- SAMRC Unit on Child and Adolescent HealthUniversity of Cape TownCape TownSouth Africa
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Hatherill M, White RG, Hawn TR. Clinical Development of New TB Vaccines: Recent Advances and Next Steps. Front Microbiol 2020; 10:3154. [PMID: 32082273 PMCID: PMC7002896 DOI: 10.3389/fmicb.2019.03154] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Accepted: 12/30/2019] [Indexed: 11/28/2022] Open
Abstract
Mycobacterium tuberculosis (Mtb) kills more people worldwide than any single infectious pathogen, yet the only vaccine licensed against tuberculosis, Bacille Calmette Guerin (BCG) is approaching its centenary. Two recent advances in clinical tuberculosis vaccine development have invigorated the field. BCG revaccination of interferon-gamma release assay (IGRA) negative adolescents provided 45% protection against sustained Mtb infection defined by IGRA conversion; and the protein-subunit vaccine M72/AS01E provided 50% protection against progression from Mtb infection to tuberculosis disease in IGRA-positive adults. These findings provide encouraging evidence for pre-exposure and post-exposure approaches to vaccination against tuberculosis, both of which may be necessary to rapidly interrupt the cycle of Mtb transmission and sustain long-term impact on global tuberculosis control. New trials are needed to demonstrate efficacy of M72/AS01E with greater precision, in a wider age range, in diverse epidemic settings, and in populations that include Mtb-uninfected and HIV-infected persons. Modeling the impact of mass campaigns with M72/AS01E and other fast-follower vaccine candidates will be crucial to make the use case and demonstrate public health value for TB endemic countries. The size and scope of the next generation of efficacy trials, and the need to expand and accelerate the existing clinical development pipeline, will require public and private consortium funding and concerted political will.
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Affiliation(s)
- Mark Hatherill
- South African Tuberculosis Vaccine Initiative (SATVI), Division of Immunology, Department of Pathology, Institute of Infectious Disease & Molecular Medicine, University of Cape Town, Cape Town, South Africa
| | - Richard G White
- TB Modelling Group, TB Centre - Centre for the Mathematical Modelling of Infectious Diseases, Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Thomas R Hawn
- Division of Allergy and Infectious Diseases, Department of Medicine, University of Washington, Seattle, WA, United States
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