Funding for this research was provided by:
National Research Foundation
Poliomyelitis Research Foundation (PRF 20/22)
National Health Laboratory Service
South African Medical Research Council
University of Pretoria
South African Department of Science and Innovation
Division of Intramural Research, National Institute of Allergy and Infectious Diseases
Received: 4 November 2021
Accepted: 7 March 2022
First Online: 28 March 2022
Change Date: 5 May 2022
Change Type: Correction
Change Details: A Correction to this paper has been published:
Change Details: https://doi.org/10.1186/s12985-022-01803-4
: Ethics approval was obtained for this study from the Faculty of Health Sciences Research Ethics Committee, University of Pretoria, South Africa: Reference number 282/2020. Written consent was obtained from all participants in the parent study (Ethics reference: 295/2015) [CitationRef removed].
: Not applicable.
: The authors declared no competing interest.