The Health Ministry has said the H7N9 bird flu cases in China are isolated, and there is no evidence of human-to-human transmission so far.
But it is monitoring the situation closely.
Experts said that there is currently limited understanding of the H7N9 virus, and more study is needed.
However, experience shows that influenza viruses are usually species-specific.
Associate Professor Leo Yee Sin, clinical head of the Communicable Diseases Centre at Tan Tock Seng Hospital, said: “In other words, they will only infect certain species in the environment, or certain limited species in the environment. Very rarely do we see cross-species infection. For example for influenza virus, there are a lot of these influenza viruses in the environment, carried by different migrating birds and waterfowl, but under very unusual circumstances, would you see a jump from animal to human.
Source: Channel News Asia
4 Ill in Jiangsu China :http://www.todayonline.com/chinaindia/china/4-more-seriously-ill-h7n9-virus-jiangsu
2 dead in Shanghai China :http://www.todayonline.com/chinaindia/china/two-deaths-shanghai-h7n9-bird-flu#inside