Q: If you place a needle on a manufacturer-filled syringe and then don’t administer the vaccine, how long can you store the syringe with the needle attached?

A: In general, a vaccine should not be prepared until the provider is ready to administer it to a patient. This is because once the syringe cap is removed or a needle is attached, the sterile seal is broken. However, if a sterile seal has been broken, staff should be sure to maintain the syringe at the appropriate temperature and either use it or discard it at the end of the clinic day. This issue is addressed in the CDC Storage and Handling Toolkit, available at www.cdc.gov/vaccines/hcp/admin/storage/toolkit/storage-handling-toolkit.pdf, page 38.