1. Department of General Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India;
2. Department of Microbiology, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India;
3. Department of Pathology, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India;
4. Department of Geriatric Medicine (Previously Department of General Medicine), Institute of Medical Sciences, Banaras Hindu University, Varanasi, India