Two months after arriving at Calcutta with Gaffky and Fischer - he had observed the comma-shaped bacillus in seventy cholera victims. His final communication from India (4 March 1884) designated village ponds - used for drinking water and all domestic purposes - as sources of localized outbreaks.....Later in May 1897 - when he reached Bombay - bubonic plague was epidemic in upper India. For working on which disease - who was awarded the Nobel Prize in Medicine