Reading-Broad Street Killer

In the homers we have read a article 'Broad Street Killer' it's about this disease cholera that was being spread on broad street.At first people thought it was a killer on the loose but it was actually a disease.DR Snow had thought that it was being spread by the water from the wells on the streets.But nobody believed him because (A) he didn't have any evidence and (B) people thought it was a murderer.