The health department, civic bodies and police will together run surveillance and shift family members and other close contacts of a person testing positive for Covid-19 to a quarantine centre but will not shut down entire neighbourhoods, government officials said.

Chief minister Mamata Banerjee said on Saturday entire neighbourhoods would not be sealed off or markets shut because of one coronavirus case.

Mamata said the Calcutta Municipal Corporation would do the needful whenever a resident in the city tested positive for the coronavirus. “A similar protocol will be followed by the Bidhannagar and Howrah municipal corporations,” an official said.

Before the chief minister’s clarification, there was fear that markets would shut down in places where positive cases have been reported.

“No market will be closed. We will only enforce the lockdown but markets will remain open.... But people cannot loiter around,” Mamata said.

A CMC official said: “Our roles are clearly demarcated. The state health department will shift family members and other close contacts of a patient to the quarantine centre in New Town. The CMC will conduct awareness campaign in the neighbourhood, sanitise public places in the area and run health surveillance of the residents.”

The police, too, will join in the effort to inform people about the regulations. An officer of Calcutta police said they would continue awareness drive over public address system, asking people to stay indoors and step out only if there is an emergency or to collect essential items. “We have been repeatedly telling people not to rush because all essential items are available in the market,” said an officer.

Calcutta police have been monitoring the markets to ensure there is no hoarding and shoppers maintain social distancing norms.

Bidhannagar police have launched five cars to help senior citizens, persons with disabilities and others to reach markets. The cars will run round the clock till the lockdown is lifted and can be booked by dialling +91- 62916-06161 (toll free).

CMC sources said the awareness campaign would highlight basic preventive measures such as washing hands with soap or cleaning them with an alcohol-based hand rub and maintaining social distancing.

A doctor working with the CMC said they “sanitise the public places around the homes of Covid-19 cases for three to four days after a person tests positive”. Sanitisation is done, usually by the civic body’s conservancy workers, with a one per cent sodium hypochlorite solution.

The Bidhannagar Municipal Corporation, too, will conduct sanitisation drive in areas under its control, an official of the civic body said.

The chief minister said: “We will be extra careful in all places from where cases are reported. We will sanitise the area. We will make people understand that they should not step out, but markets will not close down.”

Apart from sanitising the neighbourhood of a positive person, the municipal corporations in Calcutta, Bidhannagar and Howrah are also sanitising public spaces in areas under their supervision. These include hospitals and health clinics run by the corporations and roads.

Another doctor with the CMC said a health condition surveillance in the immediate neighbourhood of an infected person starts soon after the person tests positive.

The surveillance includes visiting every house. Health workers ask if anyone is running a temperature or suffering from respiratory distress or dry cough — symptoms of Covid-19.

“If someone reports a symptom, he or she is first asked to visit the local CMC clinic. A doctor examines the person at the clinic,” said the CMC doctor. If the doctor feels so, he or she may ask the person to visit a hospital.

So far, more than 40 positive cases have been reported from the CMC area.

The civic body has contacted the market committees and asked them to make a list of grocers, medicine stores, and shops selling fish, vegetables and meat. “The panels have been asked to coordinate with councillors and give a contact number that the residents can use to place orders,” mayor Krishna Chakraborty said.