GENEVA (Reuters) - An international team of flu experts will go to China this week to help with investigations into the deadly H7N9 virus, the World Health Organization (WHO) said on Tuesday.
The new strain of avian flu has killed 14 among 63 people known to have been infected, but no human-to-human spread of the virus has been confirmed.
"We're still trying to find out more information about the reservoir (of the virus). From what we know at the moment, the poultry markets have been a focus of attention, but the fact-finding mission will be looking into this as a key target of its research," WHO spokesman Glenn Thomas told a regular U.N. news briefing in Geneva.
The team includes four specialists in areas such as emerging viruses, human-to-animal flu viruses and epidemiology, as well as an unspecified number of WHO staff, Thomas said. Another WHO spokesman, Gregory Hartl, said it would be made up of eight people in all.
One of the points the mission wants to investigate is how some people seem to fight off the infection.
"There are some examples of mild cases, and also some cases of people improving, who have gone from critical to a stable condition, and that is something that will be explored by the fact-finding mission," Thomas said.
China confirmed on Saturday a seven-year-old child had been infected by the virus in the capital Beijing, the first case outside the Yangtze river delta region in eastern China where the new strain emerged last month.
No exact date has been set yet for the arrival of the team which is expected to hold talks in Beijing and visit affected provinces, he said.
The mission - made up of American, European, Australian and Chinese experts - will get underway by Saturday and is expected to carry out a week-long study, Thomas said.
In a statement issued late on Monday, the WHO said more than 1,000 close contacts of the people confirmed as having H7N9 were being closely monitored for symptoms. "So far, there is no evidence of ongoing human-to-human transmission," it said.
Another U.N. agency, the Food and Agriculture Organization, is also working with Beijing.
"We're working with the Chinese authorities to develop a market chain analysis to trace the sources of infected poultry back to the farms of origin and to identify other infected farms," FAO spokesman Silvano Sofia told the briefing.
The WHO and FAO have praised Chinese authorities for stepping up disease surveillance and conducting retrospective testing of people who had respiratory illnesses of unknown origin. Sofia said China should also be commended for making information about the virus public and available to scientists.
"The virus sequence release has allowed the scientific community to perform further analysis and to be better prepared for diagnosis and production of human vaccines," he said.
In the meantime, "the public should take routine care to prevent transmission of respiratory infection and to avoid direct contact with sick or dead poultry or livestock," he said.
China's poultry sector has recorded losses of more than 10 billion yuan ($1.6 billion) since reports emerged of the new bird flu strain two weeks ago, an official at the country's National Poultry Industry Association told Reuters on Tuesday.
(Reporting by Stephanie Nebehay and Tom Miles in Geneva; Additional reporting by Sui-Lee Wee in Beijing; Editing by Sonya Hepinstall)