The H7N9 bird flu virus has been detected in a 53-year old man in Taiwan, the island's first case, Taiwan's disease control authority confirmed Wednesday.

The Centers for Disease Control said Wednesday that the man became sick with the H7N9 bird flu virus after returning from a visit to the eastern Chinese province of Jiangsu on April 9.

It did not identify him or provide details on his condition, except to say that he had suffered from a high fever for three days.

The patient, who is Hepatitis-B-positive and suffers from high blood pressure, is in a serious condition, the statement said.

A total of 139 people who have had close contact with him are being monitored, it said.

Taiwan health authorities informed the mainland's counterpart earlier on Wednesday, the statement said.