Bacterial and fungal contaminants, which may be introduced during repeated use of a multi-dose vial, would have an opportunity to grow in the partially-used vials.

多剂量瓶重复使用过程中可能带入的细菌和真菌污染物将会有机会在没有用完的瓶中生长。

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Thimerosal, a mercury preservative found in the multi-dose vial H1N1 vaccines, has been controversially linked to autism, though no studies have proved that theory.

CNN: To vaccinate or not? Some wary on H1N1 choice