BEIJING, Oct. 15(Xinhuanet) -- Children under 10 may need two shots of swine flu vaccine to get fully protection, said American vaccine maker Sanofi Pasteur as quoted by media reports Thursday.

    U.S. Federal officials agreed,“Two-dose shots for H1N1 swine flu would accord with recommendations for seasonal influenza immunization in children of this age.”

    “The new Sanofi results back up what government tests are showing”, said Dr. Anthony Fauci, director of the American National Institute of Allergy and Infectious Diseases.

    For younger children, the protection from one shot is "modest but not sufficient to allow for one dose to do the trick," he added.

    Sanofi is the only company licensed in the United States to produce a flu vaccine for children as young as 6 months of age.

    Sanofi said results of a U.S. clinical trial on H1N1 vaccination in children aged 6 months through 9 years suggested a single dose may protect many children but "two doses of vaccine will be required for optimal protection."

    Previous results from studies of swine flu vaccines made by Sanofi and other companies have found one dose offers good protection in adults.

    The clinical test of vaccine involved 474 children. However, only 50 percent of those aged 6 to 35 months had adequate protection after a single shot, while 76 percent of children aged 3 to 9 years were protected. That compares with 98 percent of adults who had a good immune response after just one dose.

    (Agencies)