Enteropathogen antibody dynamics and force of infection among children in low-resource settings
- University of California, Berkeley, United States
- United States Centers for Disease Control and Prevention, United States
- Kenya Medical Research Institute, Kenya
- Kongwa Trachoma Project, United Republic of Tanzania
- Georgia State University, United States
- Task Force for Global Health, United States
Abstract
Little is known about enteropathogen seroepidemiology among children in low-resource settings. We measured serological IgG responses to eight enteropathogens (Giardia intestinalis, Cryptosporidium parvum, Entamoeba histolytica, Salmonella enterica, enterotoxigenic Escherichia coli, Vibrio cholerae, Campylobacter jejuni, norovirus) in cohorts from Haiti, Kenya, and Tanzania. We studied antibody dynamics and force of infection across pathogens and cohorts. Enteropathogens shared common seroepidemiologic features that enabled between-pathogen comparisons of transmission. Overall, exposure was intense: for most pathogens the window of primary infection was <3 years old; for highest transmission pathogens primary infection occurred within the first year. Longitudinal profiles demonstrated significant IgG boosting and waning above seropositivity cutoffs, underscoring the value of longitudinal designs to estimate force of infection. Seroprevalence and force of infection were rank-preserving across pathogens, illustrating the measures provide similar information about transmission heterogeneity. Our findings suggest antibody response can be used to measure population-level transmission of diverse enteropathogens in serologic surveillance.
Data availability
Analyses were conducted in R version 3.5.3. Data and computational notebooks used to complete the analyses are available through GitHub and the Open Science Framework (osf.io/r4av7).
Article and author information
Author details
Funding
National Institutes of Health (K01-AI119180)
- Benjamin F Arnold
Bill and Melinda Gates Foundation (OPP1022543)
- Patrick J Lammie
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: In Haiti, the human subjects protocol was reviewed and approved by the Ethical Committee of St. Croix Hospital (Leogane, Haiti) and the institutional review board at the US Centers for Disease Control and Prevention (CDC). After listening to an overview of the study, individuals were asked for verbal consent to participate. Verbal consent was deemed appropriate by both review boards because of low literacy rates in the study population. With each longitudinal visit, the study team re-consented participants before specimen collection. Mothers provided consent for children under 7, and children 7 years and older provided additional verbal assent. In Kenya, the human subjects protocol was reviewed and approved by institutional review boards at the Kenya Medical Research Institute (KEMRI) and at the US CDC. Primary caretakers provided written informed consent for their infant child's participation in the trial and blood specimen collection and testing. The original trial was registered at clinicaltrials.org (NCT01695304). In Tanzania, the human subjects protocol was reviewed and approved by the Institute for Medical Research Ethical Review Committee in Dar es Salaam, Tanzania and the institutional review board at the US CDC. Parents of enrolled children provided consent, and children 7 years and older also provided verbal assent before specimen collection.
Reviewing Editor
- Mark Jit, London School of Hygiene & Tropical Medicine, and Public Health England, United Kingdom
Publication history
- Received: January 29, 2019
- Accepted: August 15, 2019
- Accepted Manuscript published: August 19, 2019 (version 1)
- Version of Record published: September 16, 2019 (version 2)
Copyright
This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.
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Enteropathogen antibody dynamics and force of infection among children in low-resource settings
eLife 8:e45594.
https://doi.org/10.7554/eLife.45594
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