Angry parents have accused a township health service center in Taixing, Jiangsu Province, of using their children as guinea pigs after it was found to have injected more than 100 of them with vaccines still under clinical trial.

Both the health center in Fenjie Town and the Taixing City Disease Control Center admitted that the vaccine was not yet on the market but insisted that the trial had been approved by parents, the Modern Express reported yesterday.

However, parents said they had no idea it was a trial when their children took part in January last year.

Li Wei said the center had asked him to bring his two-year-old daughter to have a free hand-foot-and-mouth disease vaccine a year ago. He understood that 200 children would be taking part in the inoculation program.

"I felt confused as I was told my daughter needed to have blood tests regularly after the inoculation," Li said.

Li told the newspaper that his daughter had tested positive in two blood tests, but the newspaper did not specify what the tests were for.

He told reporters he searched online and found that the vaccine had not been approved for use but was still under clinical trial.

Another parent, Fang Yun, told the newspaper that her daughter had contracted hand-foot-and-mouth disease two months ago and said a worker at the center had told her secretly that the vaccine had some problems.

"No one ever told me it was a trial," Fang said.

An official surnamed Gu at the center told the newspaper the program was nationwide and the center was just one of many places where it was carried out. The trial was conducted with the approval of parents, Gu added.

Yao Genhong, an official with the disease control center, said parents had all signed on agreements for the project, but he failed to provide any documentation when asked.