A sign warning tourists not to contact with seagulls is seen at the seashore in Qingdao city, East China's Shandong province, April 14, 2013.[Photo/Xinhua]

A sign warning tourists not to contact with seagulls is seen at the seashore in Qingdao city, East China's Shandong province, April 14, 2013. The city has suspended trade of live poultry and warned people to avoid contact with birds, as an effort to prevent the H7N9 infections. The total number of confirmed human infections of the H7N9 bird flu in China has risen to 51, as two new cases were reported in Central China's Henan province on April 14.