Complicating the already complex process of distributing swine flu vaccine is the fact that there are eight vaccine formulations, each intended for use by somewhat different populations - and made by four different companies:
■ Sanofi Pasteur 0.25 milliliter prefilled syringes for children between the ages of 6 months and 35 months
■ Sanofi Pasteur 0.5 milliliter prefilled syringes for patients 3 and older
■ Sanofi Pasteur vials that provide shots for multiple patients 6 months and older
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■ Novartis vials that provide shots for multiple patients 4 and older
■ CSL prefilled syringes for patients 18 and older
■ CSL vials that provide shots for multiple patients 18 and older
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