1. Department of Virology, Faculty of Basic Medical Sciences, College of Medicine, University of Ibadan, Ibadan, Nigeria
2. Centre for Human Virology and Genomics, Department of Microbiology, Nigerian Institute for Medical Research, Lagos, Nigeria
3. Infectious Diseases Institute, College of Medicine, University of Ibadan, Ibadan, Nigeria
4. Division of Virology, National Institute for Biological Standards and Control, Potters Bar, Hertfordshire, United Kingdom
5. WHO National Polio Laboratory, University of Ibadan, Ibadan, Nigeria