The number of people in China stricken with the H7N9 strain of bird flu has risen to 104, the World Health Organization announced on Monday.
Chinese officials said six new cases of bird flu, including five in Zhejiang province and one in Jiangsu, had been detected over the weekend, Xinhua News reported. The WHO confirmed an additional two cases in Zhejiang on Monday, citing new information from the National Health and Family Planning Commission.
Twenty-one people have died from the virus, WHO said, while 70 bird flu patients are currently hospitalized, according to CNN.
The most deaths and cases of infection have occurred in eastern China, though four people in the northern and central parts of the country — one in Beijing and three in Henan Province — also have the virus, CNN said.
On Friday, international and Chinese health experts began a weeklong, WHO-sponsored investigation into how H7N9 — a strain of bird flu not seen before three weeks ago — is transmitted.
About 40 percent of patients have claimed they had no direct contact with live poultry or other birds, which makes transmission "very difficult to understand," Dr. Masato Tashiro, director of WHO's influenza research center in Tokyo, told the Associated Press.
People have potentially been exposed to the virus at live poultry markets where birds are slaughtered or from migratory bird droppings, health experts say.
"People can still get exposed to the fecal material with viruses without noticing it or without direct contact with poultry or wild birds themselves," David Hui, an infectious diseases expert at the Chinese University of Hong Kong, told the AP.
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