Eight city residents were detected with cholera in the first eight days of this month, according to the Brihanmumbai Municipal Corporation (BMC) data.
Last month, 12 people were treated for cholera in the city Doctors are worried over the rising number of cases, which was unheard of in the past few years.
"Till last year, we had sporadic cholera cases, which tested positive in the preliminary hanging drop test. But these eight have tested positive in the confirmatory culture test, which detects the presence of cholera causing bacteria," said Manisha Mhaiskar additional municipal commissioner, Brihanmumbai Municipal Corporation (BMC).
The National Institute of Cholera and Enteric Disease receives samples of 20,000 gastroenteritis patients annually, of which 20% test positive for cholera.
Three of the eight cholera patients belong to B Ward, which includes Dongri, Yellow Gate and Pydhonie area, while two cases each were reported from E Ward (Byculla, Chichpokli) and Mumbai Central region.
According to health experts every gastroenteritis case is predisposed to cholera and people should be cautious and maintain personal hygiene.
Between July 1 and July 8 the city has reported 686 gastroenteritis cases.
"There will be many more cholera cases and these cases are just the tip of the iceberg.
In cholera, the patients gets dehydrated very quickly and pass stool continuously, whereas in gastroenteritis the patient may pass stools eight to 10 times a day," said Dr Viral Patrawala, gastroenterologist at Dr LH Hiranandani Hospital, Powai.