BEIJING - A boy entering the Chinese mainland from the Hong Kong Special Administrative Region has been confirmed as infected with H7N9 bird flu, China's quarantine authority said on Monday.

Infection of the six-year-old boy, found in the city of Shenzhen across the border from Hong Kong, marks the first human H7N9 case for tourists entering the Chinese mainland, said the General Administration of Quality Supervision, Inspection and Quarantine.

The case was first noted on January 28 when the boy was diagnosed with a fever of 38.2 degrees Celsius and other symptoms such as a red throat and swelling tonsils, and confirmed later by the quarantine authorities and disease control center of Guangdong Province.

China has reported more than 120 human H7N9 cases this year, including over 26 deaths, with the provinces of Zhejiang and Guangdong worst affected.