Many Calcuttans are down with fever, cough and sore throat and doctors are blaming air pollution, along with viruses, for the spurt in ailments.

Hospitals said many patients are admitted with fever and respiratory distress and the demand for critical care beds has shot up at some of the healthcare facilities over the past week, officials said.

According to doctors, people from all age groups are contracting viral infections and suffering from ailments linked to air pollution.

“Some of those coming to my clinic with fever are testing positive for mosquito-borne viral infections such as dengue and chikungunya. Also, people are suffering from non-flu viral infections causing fever, sore throat and cough,” said Chandramouli Bhattacharya, an infectious disease specialist at Peerless Hospital.

“The flu tests for these patients are returning negative,” he said. In most cases, the fever is subsiding after two to three days.

“Air pollution is also one of the causes of respiratory distress. The pollutants reduce the immunity of the respiratory system and so people become more vulnerable to viral infections,” said Bhattacharya.

Angshuman Mukherjee, a senior consultant pulmonologist at Manipal Hospitals Mukundapur, said he is getting 10 to 12 new patients every day suffering from cold, cough and respiratory distress.

“At least 30 such patients are turning up in my clinic every day, including those who had contracted viral infections earlier and are on follow-up,” said Mukherjee.

The number of such patients has increased, post-Diwali.

“The weather conditions start changing around Diwali. Now is the ideal condition for viruses to become more active,” he said.

“The rise in air pollution is another reason for the spread of ailments. The pollutants being breathed in enter the respiratory tracts, causing irritations, sore throat and cough,” said Mukherjee.

Doctors suggest that adults vaccinate themselves against influenza, pneumonia, Herpes Zoster and Pertusis.

Children, too, are suffering from viral infections.

“Ten to 12 per cent of the children coming to the clinic are suffering from fever and rash. These are mostly caused by viral infections,” said Apurba Ghosh, the director of the Institute of Child Health.

Hospitals attribute their high occupancy rates to patients getting admitted with fever and respiratory conditions.

“Most of the patients getting admitted with fever and chest infections are elderly people,” said Pradip Tondon, the CEO of Belle Vue Clinic.

At Woodlands Multispeciality Hospital, all 45 critical care beds were full on Sunday evening.

“Many of the patients are suffering from respiratory distress. There are a lot of queries for critical care beds and there is a waiting list,” said Rupak Barua, the managing director and CEO, Woodlands Multispeciality Hospital.