A top mainland respiratory disease expert has said the chance of an outbreak of the H7N9 bird flu virus becoming serious in the Guangdong area is low.
Dr Zhong Nanshan said the number of people infected was small and previous serious flu outbreaks had affected a higher percentage of more vulnerable groups like the elderly.
Dr Zhong, a fellow of the Chinese Academy of Sciences, also told a press conference tests for the virus needed to be improved so people who have been infected get diagnosed and treated more quickly.
Six people are known to have contracted the virus in Guangdong since August, with four getting sick this month.
Dr Zhong said he could not entirely rule out the chance of humans spreading the virus to each other, but only two possible cases of human transfer of H7N9 bird flu are now under investigation in two families in Shanghai and Jiangsu province.
"These two family members engage in very close contact, which show limited human transmission," he said.
Zhong said the condition of two of the four patients in the province who were seriously ill with the virus appeared to be worsening. This was partly due to delays in diagnosis, he said.
Three of the six people infected in Guangdong had undergone several inconclusive quick tests before doctors were finally able to confirm they had the illness with a more comprehensive genetic test. It took one patient about 13 days to be diagnosed after catching the virus.
"This shows rapid test kits are not very reliable,'' said Zhong. "This needs to be improved, but it's a worldwide issue," he said.
The industry and commerce department in Guangdong has ordered a temporary shutdown of poultry markets for sterilisation tomorrow, at the end of the year and before the Lunar New Year holiday.
The provincial authorities said the supply of live poultry to Hong Kong would continue as long as the livestock tested negative for the bird flu virus.
Meanwhile, Xinhua has reported an outbreak of the H5N2 bird flu virus at a poultry farm in Baoding in Hebei province. The farm has been sealed off. About 4,000 chickens raised at the farm were found to have the illness.
A new strain of bird flu in humans, H10N8, was confirmed in Jiangxi province on Wednesday. A woman, 73, died of the illness.