1. Department of Medical Microbiology and Parasitology, Obafemi Awolowo University, Ile-Ife, Osun State, Nigeria
2. Department of Virology, College of Medicine, University of Ibadan, Ibadan, Oyo State, Nigeria
3. Department of Microbiology, Faculty of Science, Ekiti State University, Ado-Ekiti, Ekiti, State, Nigeria
4. WHO National Polio Laboratory, University of Ibadan, Ibadan, Oyo State, Nigeria