The Olympics' top anti-doping official said Friday that drug use by athletes in China was no worse than in any other country.

Prince Alexandre de Merode, chairman of the International Olympic Committee's medical commission, downplayed the recent spate of positive tests involving Chinese athletes as isolated cases.While ruling out any systematic doping program in China, de Merode called on Chinese sports bodies to take tough sanctions against any coaches or officials who might be responsible for providing drugs to athletes.

Eleven Chinese athletes, including world champion women swimmers Yang Aihua and Lu Bin, tested positive for performance-enhancing drugs at the Asian Games in Japan in October. It's believed to be the highest number of positive tests by athletes from a single country at any major competition.

But de Merode said there was no reason to single out China.

"The Chinese had a delegation of 500 athletes at the Asian Games, and about 10 positive cases is not such a high percentage," de Merode said.

"There are no more cases in China than anywhere else," he said. "These are epidemics that occur on occasion."

De Merode rejected suggestions that the number of cases indicate that China is involved in an organized, systematic doping campaign similar to the one that operated in former East Germany.

"There is no politics of systematic doping in China," he said. "It's limited to certain sports."