There is an isolation ward at the government-run hospital in eastern Kolkata where three people are admitted, people familiar with the matter said. But Dr Chakraborty said they are not Nipah patients.
Thirteen people have died of the Nipah virus in Kerala.
"The patients were whimsically referred to us from the districts. We have checked their symptoms and we are sure it is not Nipah virus," the Director of Health Services said. "The patients are on antibiotics and responding well. There is absolutely no need to panic."
Ever since Nipah virus deaths were reported from Kerala last week, there has been panic across the country, including Bengal, which has seen at least two episodes of Nipah virus attacks in the past.
In 2003, several people had died of the virus in Siliguri in north Bengal. In fact, the Nipah virus is still referred to sometimes as the Siliguri virus.
"We treat one crore outdoor patients every month. They are all being properly investigated and will be tested for Nipah, only if there are medical symptoms of the virus. These patients do not have any such symptoms," Dr Chakraborty said.
Other states are also paying close attention to patients who show symptoms of the deadly virus. The state-run Goa Medical College and Hospital has kept under observation a 20-year-old Kerala resident who was found having symptoms of the Nipah virus.
The Goa government has formed a committee, headed by the coastal state's health secretary, to draw a protocol to deal with Nipah virus cases, if any, in the state.
In Tamil Nadu, state health minister C Vijaya Baskar has said the government has taken precautionary steps to prevent the appearance of the virus in the state. "I categorically say there are no cases of Nipah virus in Tamil Nadu. In the two suspected cases reported in Kerala, I think they are still carrying out tests to ascertain if it is of the virus," he told reporters.