Fever, often accompanied by cold and cough, affected several households across the city during the festive season.
Seasonal flu, H1N1 or swine flu, and influenza B are among the infections currently circulating in the city, health experts said. While most patients recover at home, some have required hospital admission, doctors said.
“Some patients have been admitted with malaria and some with influenza B. Those with malaria have been admitted in the past two or three days, while the others were admitted over the past seven to 10 days,” said Chandramouli Bhattacharya, an infectious disease expert at Peerless Hospital.
Those admitted with influenza-like symptoms are mostly elderly or immunocompromised patients, he said.
Influenza B is a generally milder form of influenza, with symptoms usually subsiding within two or three days.
Doctors do not routinely recommend tests unless a patient requires hospitalisation.
“Most cases are seasonal flu, including H1N1. All these infections are contagious, and transmission rates are high,” said Suman Saha, consultant microbiologist at Narayana Health RN Tagore Hospital.
Seasonal changes, accompanied by greater differences between day and night temperatures, can increase virus transmission, he said.
The viruses spread through the air and via respiratory droplets released during coughing, Saha said. Children can contract infections from adults, while adults can also catch them from children.
Fever is not always high-grade but may last a day or two longer than usual, he said.
“Viral fever usually subsides within a couple of days, but in these cases it may persist for another day or two. Weakness can continue even after the fever subsides,” Saha said.
Outpatient departments at several facilities remained closed during the four days of Puja, but doctors continued to receive calls from patients.
“Children aged seven to 17 came with complaints of gastroenteritis and dysentery. During Puja, children and adults often eat out, and the source of the water used to prepare the food may be unknown. Contaminated water can lead to infections,” said Apurba Ghosh, executive director of the Institute of Child Health.