The researchers studied over 200 cases in different parts of India of which 20 cases where studied in Hyderabad.
Links:
[1] http://admin.indiaenvironmentportal.org.in/news/hyderabad-dirty-street-drinks-give-cholera
[2] http://admin.indiaenvironmentportal.org.in/category/newspaper/deccan-chronicle-telangana
[3] http://admin.indiaenvironmentportal.org.in/category/thesaurus/telangana
[4] http://admin.indiaenvironmentportal.org.in/category/thesaurus/waterborne-diseases
[5] http://admin.indiaenvironmentportal.org.in/category/thesaurus/cholera
[6] http://admin.indiaenvironmentportal.org.in/category/thesaurus/health-effects
[7] http://admin.indiaenvironmentportal.org.in/category/thesaurus/drinking-water
[8] http://admin.indiaenvironmentportal.org.in/category/thesaurus/water-pollution
[9] http://admin.indiaenvironmentportal.org.in/category/thesaurus/water-quality