TAIPEI, Taiwan (AP) — Taiwan heightened surveillance of travelers from China on Thursday after authorities confirmed the island’s first case of a new deadly strain of bird flu.

The 53-year-old man became ill with fever after returning from a visit to the eastern Chinese province of Jiangsu on April 9, the Centers for Disease Control said.

Commuters wear masks at a subway station in Taipei, Taiwan, Thursday. Pic: AP.

He twice tested negative for H7N9 but eventually tested positive Wednesday after his condition deteriorated, CDC official Chang Feng-yi said.

He said Thursday authorities will step up screening of visitors from China at airports for signs of fever and other ailments. News reports said Taiwanese airlines will suspend providing chicken and ducks that come from China.

China and Taiwan have close trade and economic ties. An estimated 1 million Taiwanese live on the mainland. Many Taiwanese laptop and other electronics makers have operations in Jiangsu province, where the first case of H7N9 was confirmed March 31.

Some 6,000 Chinese tourists visit Taiwan every day.