In the last two years, the civic body had not reported a single positive case of cholera.
“We had patients who tested positive for the cholera bacteria in the hanging drop test but not in the confirmatory culture test. This year, we are testing all suspected cholera case with the confirmatory test,” said Manisha Mhaiskar, additional municipal commissioner, Brihanmumbai Municipal Corporation (BMC).
Of the 40 cholera cases, eight were reported from E ward (Byculla) followed by six cases from G south (Prabhadevi).
“There is no particular area as such, where there is a spurt of cholera cases. All cases are sporadic,” Mhaiskar added.
The civic body data shows a 50% rise in gastroenteritis patients in the city compared to last July.
While 1,652 cases were reported in July last year, this July 2,481 patents have already taken ill to gastroenteritis.
Experts said that as all gastroenteritis cases are predisposed to be cholera but there could be many undetected cholera cases as well.