CDC discourages the practice of prefilling vaccine into syringes for several reasons, including:
- The increased possibility of administration and dosing errors
- The increased risk of inappropriate storage temperature
- The probability of bacterial contamination
- The probability of reducing the vaccine’s potency over time
Prefilling vaccine into syringes also violates basic medication administration guidelines, which state that an individual should administer only those medications he or she has prepared and drawn up.
Although pre-drawing vaccine is discouraged, a limited amount of vaccine may be pre-drawn in a mass-immunization clinic setting under the following conditions:
- Only a single type of vaccine (for example, influenza) is administered at the mass-immunization clinic setting
- Vaccine is not drawn up in advance of its arrival at the mass-vaccination clinic site
- These pre-drawn syringes are stored at temperatures appropriate for the vaccine they hold
- No more than 1 vial or 10 doses (whichever is greater) is drawn into syringes
- Clinic staff monitor patient flow carefully and avoid drawing up unnecessary doses or delaying administration of pre-drawn doses
At the end of the clinic day, all remaining vaccine in syringes prefilled by staff should be discarded.