Structural uncertainty in onchocerciasis transmission models influences the estimation of elimination thresholds and selection of age groups for seromonitoring
File(s)
Published version
Author(s)
Type
Journal Article
Abstract
Background. The World Health Organization recommends monitoring Ov16 serologyin children aged <10 years for stopping mass ivermectin administration. Transmission models can help to identify the most informative age groups for serological monitoring and investigate the discriminatory power of serology-based elimination thresholds.Model predictions will depend on assumed age-exposure patterns and transmission efficiency at low infection levels. Methods. The individual-based transmission model, EPIONCHO-IBM, was used toassess: i) the most informative age groups for serological monitoring using receiveroperator characteristic curves for different elimination thresholds under various age-dependent exposure assumptions, including those of ONCHOSIM (another widely-used model), and ii) the influence of within-human density-dependent parasite establishment (included in EPIONCHO-IBM but not in ONCHOSIM) on positive predictive values for different serological thresholds.Results. When assuming EPIONCHO-IBM exposure patterns, under-10s are themost informative age group for seromonitoring; when assuming ONCHOSIM’s exposure patterns, 5–15-year olds are the most informative (as published elsewhere).Omitting density-dependent parasite establishment results in more lenientseroprevalence thresholds, even for higher baseline infection prevalence and shorter treatment durations.Conclusions. Selecting appropriate seromonitoring age groups depends critically onage-dependent exposure patterns. The role of density dependence on elimination thresholds largely explains differing EPIONCHO-IBM and ONCHOSIM elimination predictions.
Date Issued
2020-06-15
Date Acceptance
2019-12-16
Citation
Journal of Infectious Diseases, 2020, 221 (Suppl. 5), pp.S510-S518
ISSN
0022-1899
Publisher
Oxford University Press (OUP)
Start Page
S510
End Page
S518
Journal / Book Title
Journal of Infectious Diseases
Volume
221
Issue
Suppl. 5
Copyright Statement
© The Author(s) 2020. Published by Oxford University Press for the Infectious Diseases Society of America.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited.
Sponsor
Medical Research Council (MRC)
The Task Force for Global Health
Grant Number
MR/R015600/1
1708CR001/VP1 (OPP1184344)
Subjects
Ov16 serology
age-dependent exposure
density dependence
elimination
ivermectin
microfilarial prevalence
onchocerciasis
positive predictive value
receiver operating characteristic curve
threshold
06 Biological Sciences
11 Medical and Health Sciences
Microbiology
Publication Status
Published
Date Publish Online
2020-03-16