A 4-year-old boy confirmed with H7N9 bird flu on Thursday has recovered, a disease control and prevention official in Shanghai said on Monday.

"From a clinical point of view, the boy has recovered," said Wu Fan, director of the Shanghai Disease Control and Prevention Center.

The boy's recovery proves not every human infection of H7N9 is severe, Wu said. The boy will need to remain in the hospital for further observation, Wu added.