Shanghai reported two cases of H7N9 infection yesterday, bringing the city's total to 13, including five fatalities.
Eight patients are now being treated in isolation but none of their close contacts had tested positive, the Shanghai Health and Family Planning Commission said.
The latest cases are both Shanghai retirees and they are said to be in a stable condition.
A 62-year-old man began to develop a fever on April 1 and went to a branch of the Shanghai No. 1 People's Hospital, where he was treated for an upper respiratory tract infection.
When his condition didn't improve he returned to the hospital last Friday and was found to be suffering from pneumonia.
Tests by the Shanghai Center for Disease Control and Prevention confirmed an H7N9 infection.
The other new case was a 77-year-old man who began to have a fever and feel his body ache last Wednesday. He was diagnosed with upper respiratory tract infection at Pudong District People's Hospital.
On Sunday, he went to Jing'an District Central Hospital and was diagnosed with pneumonia.
He tested positive for H7N9 early yesterday.
The city government held a meeting yesterday morning to stress the importance of preventing the spread of H7N9 and of following treatment guidelines.
The health commission has set strict procedures for the diagnosis of H7N9 cases under the guidance of the national commission, it said.
It is requiring all medical facilities in the city to screen patients suffering from unexplained pneumonia and offer effective treatment to all patients with flu-like symptoms.
A combination of Western medicine and traditional Chinese medicine is being recommended during diagnosis and treatment of patients with H7N9 infection.
Hospitals are also being required to strengthen front-line medical staff for H7N9 cases and improve the success rate of treatment.
Meanwhile, an inspection of local poultry farms has found no trace of bird flu, the Shanghai Agricultural Commission said.
The city's animal disease prevention and control center collected 336 samples from poultry farms yesterday and all tested negative.
The commission said that road checks were being stepped up to prevent live poultry entering the city. Five vehicles were turned around yesterday.
The city government also urged residents to phone 12315 to report any trading in live poultry which is now banned in the city due to the current bird flu crisis.
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