The mingle of the viruses is likely to have occurred in east China's Yangtze River Delta areas covering Shanghai, Zhejiang and Jiangsu provinces.

 

　　Infections on the mainland have so far been isolated to this region.

 

　　However, researchers with the Chinese Academy of Sciences' Key Laboratory of Pathogenic Microbiology and Immunology say no genes in H7N9 were traceable to pigs.

 

　　So far, H7N9 has been found in pigeons, quails and chickens.

 

　　Researchers are now trying to make sense of the mutation of the new strain of bird flu.

 

　　They are also stepping up monitoring of bird migration paths to prevent the H7N9 from spreading.

 

　　To that end, mainland authorities say they've been collaborating with health authorities on Hong Kong and Taiwan.

 

　　Fan Liqing is with the State Council's Taiwan Affairs Office.

 

　　"We will continue to honor the agreement on medical and hygiene cooperation of cross strait, enhancing ties with Taiwan, and providing support and aid based on the situation of preventing and controlling the disease. We will take correspondent measures to prevent the spread of H7N9."

 

　　On top of sharing information, samples of the new strain of the virus are being sent to Taiwan for further testing and to help in the development of a potential vaccine.

 

　　Scientists on the mainland are in the process of developing a vaccine for H7N9, which is expected to be made available in the next seven months.

 

　　As part of efforts to strengthen surveillance of the new virus, testing reagents for the H7N9 virus have been distributed to all flu monitoring sites across China.

 

　　China officially confirmed the first cases of the H7N9 virus in humans late last month.

 

　　So far, there's been no discernable proof of human-to-human transmission.

 

　　World Health Organization Spokesperson Gregory Hartl.

 

　　"There is no evidence of sustained human-to-human transmission. There are some suspected but not yet confirmed cases of perhaps very limited transmission between family members. As I just said, those are still being investigated."

 

　　Meantime, the first person to recover from the H7N9 bird flu here in China has been discharged from hospital.

 

　　The 4-year old boy is now well enough to leave hospital in Shanghai.

 

　　For CRI, I'm Shen Chengcheng.