Local hospitals are reporting a big rise in numbers of patients with respiratory diseases — including H1N1 swine flu.

Tests in some hospitals found that many patients had this strain of flu, which in November became a seasonal flu type included in nationwide monitoring.

The Shanghai Center for Disease Control and Prevention said the epidemic of flu is stable in the city, but that Shanghai has entered the peak season for the bug with the arrival of cold fronts and smoggy days.

Among affected groups, many students hit by flu have been asking for sick leave.

Flu-related rumors are also circulating on social media platforms, with claims that H5N2 bird flu is coming.

The rumors say that those infected have similar symptoms to ordinary cold but with repeated fevers.

Rumormongers also warn parents not to take their children to public places and to stay away from live poultry to prevent H5N2.

But Dr Lu Hongzhou, director of the H7N9 expert group, said H5N2 is different from other avian flu viruses — such as H7N9 and H5N1 — as it doesn’t affect humans.

Xinhua Hospital said its out-patient and emergency services have been extremely busy in recent days.

The hospital created a record by providing out-patient and emergency services to 16,171 people on December 30.

Between January 1 and 7, the number of people visiting its out-patient and emergency services was up 37.7 percent on last year, while pediatric services at the hospital saw a 48 percent increase.

Dr Bai Jianwen, director of Shanghai East Hospital’s emergency department, said most patients have symptoms such as a headache, a sore throat, aches all over their body, high fever and a cough.

“Flu is different from an ordinary cold, which can be treated by drinking water and rest,” Bai said. “Flu symptoms only improve through professional treatment. If they don’t receive antibiotics, patients can develop bacterial infection three or four days later.”

Doctors said temperature fluctuations make people more susceptible to flu, while air pollutants can affect the immune system. People with a weak immune system are more likely to develop serious symptoms.

To reduce the chance of coming down with a winter bug, experts advise avoiding going to crowded places and washing your hands frequently.