BEIJING (AFP) - A seven-year-old girl was confirmed as Beijing's first human case of H7N9 bird flu on Saturday, local authorities said, as China's outbreak of the disease spread to the capital.
The girl, whose parents are poultry traders, was in a stable condition in hospital, the Beijing health bureau said. Her mother and father had been quarantined for observation but had shown no symptoms so far, it added.
She developed a fever, sore throat and headache on Thursday, it said, and her parents took her to hospital. Samples from her tested positive H7N9 the following day, and the national disease control centre confirmed the results on Saturday.
Chinese officials announced nearly two weeks ago that they had found the H7N9 strain in humans for the first time, and the girl brought the number of confirmed infections in the outbreak to 44, 11 of whom have died.
All previous cases had been confined to eastern China.
Experts fear the prospect of such viruses mutating into a form easily transmissible between humans has the potential to trigger a pandemic.
But the World Health Organisation (WHO) said this week that there was as yet no evidence of human-to-human transmission of H7N9.
Health authorities in China say they do not know exactly how the virus is spreading, but it is believed to be crossing to humans from birds, triggering mass poultry culls in several cities.
The United Nations' Food and Agriculture Organisation (FA0) has said H7N9 shows "affinity" to humans while causing "very mild or no disease" in infected poultry, making finding the source of transmission more difficult.
The statement from the Beijing health bureau did not say whether the girl or her family members had recently travelled to any of the areas where H7N9 infections have been identified.
But Mr Cheng Jun, vice-director of Ditan hospital, where the girl was being treated, told state broadcaster CCTV: "Ever since the outbreak started in Shanghai we have been making preparations." Beijing, which has a population of more than 20 million, has already banned live poultry trading and pigeon releases, the health bureau said.
Authorities have also ordered stepped-up surveillance of wild birds in the city and people at risk of infection, such as poultry farmers, transporters and vendors, it added.
Shanghai has had 20 confirmed cases so far and was the first to halt trading in live poultry and cull birds last week, followed by other cities in eastern China.
US fast food giant KFC, already hit by an earlier scandal in China over antibiotics in chicken, saw March sales in the country plunge 16 per cent, with parent Yum! Brands saying bird flu publicity had "a significant, negative impact".
In 2003 Beijing was accused of trying to cover up the outbreak of Severe Acute Respiratory Syndrome, which went on to kill about 800 people globally.
But it has been praised for transparency over H7N9, with the WHO saying it was pleased with the level of information sharing and US scientists congratulating it for "the apparent speed with which the H7N9 virus was identified" in a New England Journal of Medicine article.
China has said it expects to have a vaccine ready in seven months but in the article the US experts said developing one could take "many months".