He has thirty (30) years experience in teaching and research in various aspects of infectious diseases transmission, pathology, treatment, prevention and control. He has published 166 articles in peer-reviewed scientific journals. In addition, he has a keen interest in health research ethics, and received advanced training in research ethics through a Fogarty Grant of the NIH leading to a Postgraduate Diploma in Health Research Ethics from Stellenbosch University. He is very personate about clinical research and ethical standards in the conduct of health research in developing countries, and have trained research ethics committee members in Kenya on principles of bioethics, and on international guidelines and regulations of research ethics.