The Child Ecosystem and Childhood Pulmonary Tuberculosis: A South
African Perspective
Teresa DeAtley,1 Lesley Workman,2Grant Theron,3 Sabine Bélard, 2,4,5Margaretha Prins,2 Lindy Bateman,2Martin P Grobusch,4,6 Keertan
Dheda,11,12 Mark P Nicol,8 Katherine
Sorsdahl,9 Caroline Kuo,1,10 Dan J
Stein,10 Heather J Zar2
- Brown University School of
Public Health, Department of Behavioral and Social Sciences Brown
University School of Public Health, 121 S Main St, Providence, Rhode
Island 02903, USA
- Department of Paediatrics and Child Health, Red Cross War Memorial
Children’s Hospital, and SAMRC unit on Child and Adolescent Health,
University of Cape Town; Cape Town, South Africa.
- DST/NRF Centre of Excellence for Biomedical Tuberculosis Research,
South African MRC Centre for Tuberculosis Research, Division of
Molecular Biology and Human Genetics, Faculty of Medicine and Health
Sciences, Stellenbosch University, Tygerberg, South Africa.
- Center of Tropical Medicine and Travel Medicine, Amsterdam University
Medical Centers, location AMC, University of Amsterdam, Amsterdam, The
Netherlands.
- Department of Paediatric Pneumology and Immunology, Charité -
Universitätsmedizin, Berlin, Germany.
- Institute of Infectious Diseases and Molecular Medicine, University of
Cape Town, Cape Town, South Africa
- Lung Infection and Immunity Unit, Division of Pulmonology and
University of Cape Town Lung Institute, Department of Medicine,
University of Cape Town, Cape Town, South Africa
- Division of Infection and Immunity, School of Biomedical Sciences,
University of Western Australia, Perth, Australia and Division of
Medical Microbiology, University of Cape Town and National Health
Laboratory Services, Cape Town, South Africa.
- Alan J Flisher Centre for Public Mental Health, Department of
Psychiatry and Mental Health, University of Cape Town, Cape Town,
South Africa.
- Department of Psychiatry and Neuroscience Institute, and SA MRC unit
on Risk and Resilience University of Cape Town, South Africa
- Centre for Lung Infection and Immunity, Division of Pulmonology,
Department of Medicine and UCT Lung Institute & South African MRC/UCT
Centre for the Study of Antimicrobial Resistance, University of Cape
Town, Cape Town, South Africa.
- Faculty of Infectious and Tropical Diseases, Department of Infection
Biology, London School of Hygiene and Tropical Medicine, London, UK.
Keywords: TB risk factors, conceptual hierarchical frameworks
Corresponding Author: Professor Heather J. Zarᶧ
Department of Paediatrics and Child Health,
5th floor ICH Building,
Red Cross War Memorial Children’s Hospital
Cape Town
South Africa
Tel: 2721-658-5324
Acknowledgements
We gratefully acknowledge the contributions of the NHLS diagnostic
microbiology laboratory at Groote Schuur Hospital; the study, laboratory
and clinical staff at Red Cross Children’s Hospital and the Division of
Medical Microbiology, and the children and their caregivers.
Funding
The study was funded by the National Institute of Health, USA
(1R01HD058971-01), the Medical Research Council of South Africa, the
National Research Foundation (NRF) South Africa and the EDCTP (TB-NEAT;
IP.2009.32040.009). Prof Zar and Stein are supported by the Medical
Research Foundation of South Africa. Prof Dheda acknowledges funding
from the SA MRC (RFA-EMU-02-2017), EDCTP (TMA-2015SF-1043,
TMA-1051-TESAII, TMA-CDF2015), UK Medical Research Council
(MR/S03563X/1) and the Wellcome Trust (MR/S027777/1).
Ethical Standards
The authors assert that all procedures contributing to this work comply
with the ethical standards of the relevant national and institutional
committees on human experimentation and with the Helsinki Declaration of
1975, as revised in 2008. Written, informed consent was obtained from a
parent or legal guardian and assent from children older than seven
years. The study was approved by the Human Research Ethics Committee of
the Faculty of Health Sciences, University of Cape Town.
Abstract
Introduction
This study investigates drivers of childhood pulmonary tuberculosis
(PTB) using a childhood ecosystem approach in South Africa. An ecosystem
approach towards identifying risk factors for PTB may identify new
directions for intervention.
Methods
Data were collected as part of a prospective cohort study of children
presenting at a primary care facility or tertiary hospital with
suspected TB. Characterization of the childhood ecosystem included
proximal, medial and distal determinants. Proximal determinants included
child characteristics that could impact PTB outcomes. Medial
determinants included relational factors such as caregiver health that
might impact interactions with the child. Distal determinants included
macro-level determinants of disease such as socioeconomic status and
food insecurity. Children started on TB treatment were followed for up
to 6 months. Multivariate regression models tested independent
associations between factors associated with PTB in children.
Results
Of 1,738 children enrolled in the study, 242 (20%) of children had
confirmed PTB, 756 (63%) were started on TB treatment, and 444 (37%)
had respiratory conditions other than TB. In univariate analyses,
childhood malnutrition and caregiver smoking were associated with
treated or confirmed PTB. In multivariate analyses, proximal factors
such as male gender and hospitalization and low socio-economic status as
a distal factor were associated with PTB.
Conclusions
Interventions may need to target subgroups of children and families at
elevated risk for PTB. Screening for risk factors such caregiver health
may guide targeting, and provision of social protection programs to
bolster economic security may be important interventions for attenuating
childhood exposure to risk factors.