However, only 6,552 of the adverse reactions proved to be related to the vaccine -- a rate of 73.1 per million doses, Wang's group said.
Among the most serious were allergic reactions, which accounted for about 13 percent of all the events. Eleven cases of Guillain-Barre syndrome were reported among those vaccinated, a rate of 0.1 per million doses, which is lower than the normal rate of the disease in China, Wang's team found.
"These findings suggest that the H1N1 vaccine has a reasonable safety profile, and there is no evidence that the vaccine is associated with an increased risk of the Guillain-Barre syndrome," the researchers concluded in their report.
Commenting on the study, Dr. Bruce Farber, chief of the Division of Infectious Diseases at North Shore University Hospital in Manhasset, N.Y., said that "as we know from the H1N1 experience in the U.S. last year, our vaccine was safe.
"Despite the initial public skepticism and some cynicism, influenza vaccines are safe and effective," he added. "The risk-benefit ratio, which is what vaccines and everything in medicine is about, is overwhelmingly in favor of vaccination."
Mild side effects were more common among children aged 9 and younger who were vaccinated than for older adults, the study found.
Each year in the United States about 36,000 people die from complications from the flu, and the vaccine is the best protection against getting the flu in the first place, according to the U.S. Centers for Disease Control and Prevention.
For more information on the flu, visit the U.S. Centers for Disease Control and Prevention.
SOURCES: Marc Siegel, M.D., associate professor, medicin
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