Seasonal Flu Vaccine: High Demand Leads to Short Supply

The acute awareness of pandemic influenza (2009 H1N1) has led to an unprecedented demand for, and subsequent shortage of, vaccines for seasonal influenza. According to today's NYT, the shortage of seasonal flu vaccines is so severe that the NYC health department has asked doctors to refrain from vaccinating healthy adults younger than 65 years of age.

The number of doses of seasonal flu vaccine that were manufactured for this year, 114 million, is slightly higher than the number made last year, and about 90 million doses have been shipped so far, reports the NYT. But the shipped supply has nearly been consumed, with an estimated 85 million shots administered to date (which is about 24 million more than the number given out by this time last year). Manufacturers cannot make more seasonal flu vaccine, because they are committed to producing the pandemic flu vaccine.

Among the 5 FDA-approved vaccines for seasonal flu, a total of 248 lots have been released. (But how many packages or doses in a lot is unclear. The numbers may also vary, depending on the manufacturer or distributor. If lot numbers are uniform, then 1 lot represents about 46,000 doses [114 million divided by 248].)

Vaccine and Manufacturer	No. Lots Released	Package	National Drug Code (NDC)
Afluria; CSL Ltd	52	10 single-dose prefilled syringes	33332-009-01
		10-dose vial	33332-109-10
Fluarix; GSK	16	5 single-dose prefilled syringes	58160-876-46
Flulaval; ID Biomedical Corp of Quebec (distributed by GSK)	19	10-dose vial	19515-886-07
FluMist; MedImmune	36	10 single-dose prefilled sprayers	66019-107-01
Fluvirin; Novartis	39	10 single-dose prefilled sprayers	66521-112-02
		10-dose vial	66521-112-10
Fluzone; sanofi-pasteur	86	10 single-dose prefilled syringes (0.25 mL)	49281-009-25
		10 single-dose prefilled syringes (0.5 mL)	49281-009-50
		Single-dose vial	49281-009-50
		10-dose vial	49281-384-15

1 dose = 0.5 mL, unless otherwise indicated.

Except in the case of Flumist,* the seasonal flu vaccines contain the following inactivated viruses:

• A/South Dakota/6/2007 (H1N1) (an A/Brisbane/59/2007-like virus)
• A/Uruguay/716/2007 (H3N2) (an A/Brisbane/10/2007-like virus)
• B/Brisbane/60/2008

* Flumist contains the attenuated viruses.

N.B.--The NDC contains an initial 5-digit labeler code, which is assigned by the FDA, and a 3- or 4-digit product code, which is assigned by the drug firm.