</s>The shots, made by Sanofi Pasteur, were distributed across the country last month and most have already been used, according to the Centers for Disease Control and Prevention. The 800,000 pre-filled syringes that were recalled are for young children, ages 6 months to nearly 3 years.<br/>
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Dr. Anne Schuchat, a CDC flu expert, stressed that parents don't need to do anything or to worry if their child got one — or even two — of the recalled shots. The vaccine is safe and effective, she said.<br/>
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The issue is the vaccine's strength. Tests done before the shots were shipped showed that the vaccines were strong enough. But tests done weeks later indicated the strength had fallen slightly below required levels.<br/>
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Why the potency dropped isn't clear. "That's the $64,000 question," said Len Lavenda, a Sanofi Pasteur spokesman.<br/>
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Young children are supposed to get two doses, spaced about a month apart. Health officials don't think children need to get vaccinated again, even if they got two doses from the recalled lots, said Schuchat.<e>