NANJING - Hospital sources in East China's Jiangsu province said Wednesday that the five patients who have been diagnosed with the lesser-known H7N9 bird flu remain in critical condition.

Four of the patients are locals from four cities in Jiangsu. Another patient is from neighboring Anhui province, who was transferred to a hospital in Jiangsu's provincial capital of Nanjing for better treatment last week. None of them have shown signs of recovery.

Sources with Zhongda Hospital in Nanjing said the patient from Anhui has suffered multiple organ failure, especially in the lungs.

Gulou Hospital in Nanjing, which has been treating a local patient surnamed Xu, said the woman is still in intensive care.

All of the patients began showing symptoms of pneumonia in the second half of March, and they later tested positive for the new strain of bird flu, which has claimed two lives in Shanghai.

Among the patients in hospital care, only Xu, a poultry culler, had close contact with poultry. It is still unclear how the others were infected, and no mutual infections were discovered among them, the National Health and Family Planning Commission said Sunday.

Health authorities in Jiangsu have designated 16 leading hospitals to accept new cases in a bid to offer better treatment and reduce the mortality rate.

Sales of poultry in markets and restaurants in Jiangsu have remained stable. Long queues formed on Wednesday in front of a deli selling smoked duck, a popular local specialty, in Nanjing.

Vendors at the city's major marketplaces of Yingbin and Caixia said the city's health department sent staff to thoroughly disinfect the stalls.

"We have started to pay attention to wearing gloves during poultry culling, but we don't like to wear face masks, because we're afraid of scaring away customers. The look may make people worry about bird flu risks," said a vendor surnamed Li.

On Wednesday, Pang Xinghuo, spokesman for the Beijing Municipal Disease Control and Prevention Center, said the capital would not rule out the possibility of H7N9 cases popping up.

"The metropolitan area with a massive population flow every day can not rule out H7N9 risks. However, with the battle experiences of SARS and H1N1 influenza outbreaks, the city has been well prepared for epidemic control," he said.

He said the center has ordered hospitals to include H7N9 bird flu testing in routine monitoring and to train hospital staff on how to treat pneumonia caused by unknown factors.

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