More human infections from bird flu are expected before the spring, with sporadic human-to-human transmissions in China, according to the nation's top scientists.

The forecast was made after five human cases of bird flu were reported in Guangdong and Jiangxi provinces and in Shanghai. To date, three deaths have been confirmed from the H5N6 and H7N9 strains of the virus.

Shu Yuelong, director of the Chinese National Influenza Center said: "Don't panic, as there is zero possibility of sustainable or easy human transmissions of the bird flu virus. This means that the possibility of a mass outbreak of human bird flu can be ruled out so far."

Shu said that sustainable transmission refers to the easy and continuous secondary and tertiary transmissions of the virus among humans.

He said a majority of the human bird flu cases detected so far involved people who had contact with live birds.

Of the recent human cases reported, three from Guangdong and one from Jiangxi involved the H5N6 strain. The seven human infections from this strain detected to date all occurred in China.

The strain has a fatality rate of 67 percent, Shu said, and was first reported in Sichuan province in May 2014.

Ina recent case in Zhaoqing, Guangdong, a pregnant woman with the H5N6 strain had her baby delivered via cesarean section, according to the local health authority.

The baby was free from the virus, but the mother remained in critical condition. All her close human contacts were cleared from infection after a period of quarantine. Lu Hongzhou, head of the Shanghai Public Health Clinical Center, said the live poultry trade and markets are mainly to blame for the human infections.

He called for live poultry markets to be closed to prevent the virus from mutating and moving from birds to humans via close contacts.

Gao Fu, deputy director of the Chinese Center for Disease Control and Prevention, said such markets act as an "incubator" for different strains of the bird flu virus.

Surveillance undertaken by the Ministry of Agriculture showed the H5N6 strain is widespread among farmed poultry - both chickens and ducks - particularly in South China.

Humans are susceptible to H5N6 and "contact has to be cut off by closing live poultry markets," Gao said.

The H5N1, H7N9 and H5N6 strains of bird flu have been reported in China to date.

On Jan 8, public health authorities in Shanghai confirmed a human case of H7N9 bird flu.

The male patient, 59, lives in the city and is being treated at a hospital, the Shanghai Municipal Health and Family Planning Commission said.

The H7N9 strain was first reported to have infected humans in March 2013 in China. It is most likely to strike in winter and spring.

shanjuan@chinadaily.com.cn

(China Daily 01/15/2016 page3)