1. Department of Bacteriology, ICMR-National Institute of Cholera and Enteric Diseases, Kolkata, West Bengal, India.
2. Department of Collaborative Research Centre of Okayama University for Infectious Diseases, ICMR-National Institute of Cholera and Enteric Diseases, Kolkata, West Bengal, India.
3. Department of Epidemiology, ICMR-National Institute of Cholera and Enteric Diseases, Kolkata, West Bengal, India.
4. Department of Health and Family Welfare, Government of West Bengal, Kolkata, West Bengal, India.
5. Department of Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan.