Vaccine A potentially contaminated batch of a U.S.-made vaccine for children has not caused any adverse effects in China, but public health officials will continue to monitor the situation. This was stated by Yan Jiangying, spokeswoman of the State Food and Drug Administration.

She was responding to the worldwide recall of 1.2 million doses of the vaccine Hib produced by Merck & Co, a U.S.-based pharmaceutical maker.

“No cases have been detected in which children in China have been affected by Hib,” she said. “Medical institutions nationwide have stopped administering the vaccine, and the existing stock has been sealed.”

The company announced on Wednesday that it had discovered a sterilization problem at a factory in Pennsylvania. The subsequent recall involved Hib, a vaccine that protects against meningitis, pneumonia and other dangerous infections, and a serum that combines Hib with a hepatitis B vaccine.

About 100,000 doses of Hib have been available in China since October, Yao Rui, who works at the Merck’s Building said.

The company said on its website the chances that any individual dose of vaccine contaminated are low, and even in cases in which contamination has occurred, the amount is likely to be small.

Health officials said contaminated doses of the vaccine will cause skin irritation, swelling and redness around the spot where the shot was given.

Yao said the company had already informed drug watchdogs, centers for disease control, Merck distributors and the general public about the recall.

“However, due responsibilities such as legal liability and compensation claims from people who have been harmed by such products cannot be waived,” Yan said.