1. Department of Medical Virology, Faculty of Health Sciences, University of Pretoria, P.O. Box 2034, Pretoria 0001, South Africa
2. Enteric Viruses Research Group, Institute of Primate Research, P.O. Box 24481, 00502 Karen, Nairobi, Kenya
3. Department of Medical Virology, National Health Laboratory Service Tshwane Academic Division, Pretoria, South Africa