The Howrah civic body has started collecting blood samples of patients with fever in and around Nandibagan in Salkia after a man from the area died of dengue at a private hospital in Calcutta last week.
None of the samples has tested positive so far, a Howrah Municipal Corporation (HMC) official said.
Debashis Roy, the civic bodyís chief medical officer of health, said Ashok Verma, 59, had returned with high fever to Nandibagan in the first week of August from his ancestral home in Balia, UP.
When his condition worsened, he was admitted to the Calcutta hospital, where he died. ďWe are sure he caught the disease outside Bengal,Ē Roy added.