A 4-year-old boy has recovered from a new strain of bird flu that has killed nine people in China, a doctor said Wednesday.

The child from Shanghai is among 33 people confirmed to have been infected with the H7N9 virus. The official Xinhua News Agency said he was the first to completely recover and be discharged from a hospital.

A doctor at the Infectious Disease Department of the Pediatric Hospital affiliated with Shanghai's Fudan University confirmed the boy had recovered and left the hospital, but said she didn't know if it was the first recovery from H7N9. She refused to give her name, as Chinese officials often do.

Five new cases of H7N9 infection were reported on Wednesday. Two of those were in Shanghai, two in Jiangsu province, and one in Zhejiang province, according to the websites of the provincial and city health authorities. Both Zhejiang and Jiangsu border Shanghai.

China announced the first known cases on March 31, sparking concern among experts worldwide because it was the first time the strain of bird flu has been known to infect humans. They fear the virus could mutate in a way that allows it to spread easily among people, but so far there has been no sign of human-to-human transmission.

Chinese health officials believe people may be getting sick from direct contact with infected fowl, but the virus is hard to track because it appears to be spreading in birds without making them ill. The World Health Organization says at least two family clusters are being investigated, but that there is no evidence of infections among other contacts or health workers who cared for them. There have been no reported cases outside of eastern China.

Xinhua also said Wednesday that police in southwest China detained three people for up to 10 days for spreading false rumours online that the H7N9 virus had been detected in a live poultry market in Guizhou province. It said the report was reposted many times, causing fear among local people.

Meanwhile, Indonesia announced it is suspending the import of poultry products from China until the Chinese government confirms the country is free of the virus.