The H7N9 mutation of the bird flu virus is "more prone to human infection" than the H5N1 virus, with the fatality rate reaching 20-30%. China's National Influenza Center (CNIC) has reported athat H7N9 has killed 19 in China this year already and the total number of infections has reached 96. Although , as always, details are few and far between, CNIC's Shu Yuelong states that "the risk assessment of H7N9 epidemic outbreak is unchanged," despite the admission that the virus is more difficult to prevent as there is no obvious symptom for H7N9 infected poultry. South Korea has expanded a poultry cull on fears of contagion.
H7N9 bird flu has killed 19 in China this year already, and the total number of human infections has reached 96, according to the Chinese Center for Disease Control and Prevention.
Shu Yuelong, director of the Chinese National Influenza Center (CNIC), said on Monday that a large-scale H7N9 epidemic is unlikely during the Spring Festival holiday, as no H7N9 virus mutation that could affect public health has been identified so far.
"There is no evidence of constant inter-human transmission, and the risk assessment of H7N9 epidemic outbreak is unchanged," said Shu.
Shu reiterated that H7N9 is more prone to human infection than H5N1, with H7N9 case fatality rate reaching 20 to 30 percent.
The virus is more difficult to be prevented as there is no obvious symptom for H7N9 infected poultry, and at present the CNIC is not able to precisely predict the direction of the mutation of the H7N9 virus.
"We will continue to strengthen monitoring and carry out research," said Shu.
On Sunday, the National Health and Family Planning Commission issued a paper on H7N9 diagnosis and treatment, noting that early report, diagnosis and treatment are the best ways to prevent and control the virus.
South Korea is expanding a poultry cull in a bid to contain the spread of bird flu that has been found on an increasing number of farms around the country and in migratory birds.
The country's agriculture ministry said the H5N8 strain of bird flu had been detected on six poultry farms and that there had been 13 cases in migratory birds since the first outbreak earlier this month.
No human infection has been reported, while the ministry is looking into four additional reports from poultry farms and more than 50 other suspected cases in migratory birds, it said in a statement on Monday.
South Korea will slaughter over 1.4 million farm birds, including 644,000 that have already been killed, according to the ministry. That would be under 1 percent of the country's total 160 million poultry population.
The first case of H5N8 bird flu was found on January 17 at a duck farm in the southwestern province of North Jeolla, about 300 km (186 miles) from Seoul.