Impact of Severe Weather Conditions on Biological Products

CBER is providing interested persons with information concerning the storage and use of temperature-sensitive biological products that have been involved in a temporary electrical power failure or flood conditions. While people should not be put at risk by using a product that may be unsafe due to the conditions under which it was stored, shortages should not be created by discarding product simply because of power failures that may not adversely affect the product. Vials of biological products in contact with flood waters should be discarded given the possibility of contamination and the likelihood of significant exposure to temperatures outside of those recommended for cold chain storage.

Most biological products require specific storage conditions, as indicated in the product labeling, to maintain their safety, purity, and potency. These products include bacterial and viral vaccines, allergenic extracts, plasma derivatives, and other products requiring refrigeration or frozen storage, as well as products that can be stored at controlled room temperature (i.e., not exceptionally cold or hot). When there is an electrical power failure, whether due to accident, equipment failure, or disruption in the electrical power grid, the temperature control systems for product storage may not function. For example, on August 14, 2003, the northeast region of the country experienced a power outage lasting from one to several days, and some health professionals were uncertain what to do with products that they had in storage. Power failures are not only a concern regarding storage in a facility, as failure of the refrigeration or freezer unit on a carrier (e.g., truck) while the products are in transit may also occur. The information below may assist interested persons in determining what to do with their biological products in the event of a power failure.

Vaccines Requiring Refrigeration or Frozen Storage

Most refrigerated vaccines are relatively stable at room temperature for limited periods of time, although certain vaccines are temperature-sensitive. Products stored in a closed refrigerator (or freezer, if appropriate) during a power outage may maintain their potency unless the power outage is of such duration that the refrigerator's (or freezer's) internal temperature rises significantly. It is recommended that thermometers be located in the refrigerator and freezer section so that temperatures can be read when power resumes to see if excursions outside of recommended temperatures have occurred. The "How Supplied/Storage and Handling" section of the product label may also be consulted for information. Most vaccine manufacturers have data to support the stability of their products at somewhat elevated temperatures and related duration of storage; please call the supplier or the manufacturers' customer service department if you are concerned about the impact of temperature/time duration on product stability.

If the Power Goes Out

In the past, persons responsible for storing refrigerated or frozen biological products have taken the following actions to preserve cold storage conditions during a power outage:

• Note the time of the power outage and do not open freezers and refrigerators until power is restored. This will help keep the temperature low for a longer period of time.

When Power is Restored

• Record the temperature in the refrigerator or freezer as soon as possible after power is restored and before the temperature has begun to drop again. Continue to record the temperature at periodic intervals until it reaches the temperature range indicated on the product labeling as appropriate for product storage.

• Record the duration of increased temperature exposure. For example, the temperature of the freezer was 0 degrees Fahrenheit at noon on day 1 when the power failed; 15 degrees Fahrenheit at 6 PM on day 2 when the power was restored; 10 degrees Fahrenheit at 10 PM on day 2; and 0 degrees Fahrenheit at 7 AM on day 3. This information about time/temperature duration can enable calculations to be made by the product manufacturer, in consultation with FDA as necessary, about the continued potency of the involved products.

If a Flood is Expected

When a flood is anticipated, storage facilities have taken steps to raise stored products out of range of anticipated flood waters. For example:

• Elevate biological products stored on warehouse floors off the ground (e.g., on pallets). For those items on shelves, it may be important to securely anchor the shelves to keep products dry.

• For products stored in refrigerators at floor level, elevate refrigerators on wheels or platforms to the extent possible.

If Flooding Occurs

Vials containing vaccine exposed to flood waters should be considered contaminated and also likely to have been exposed to temperatures outside of those recommended for cold chain storage, and should be discarded.

Other Non-Blood Biologicals Requiring Refrigeration or Frozen Storage

The information above concerning the storage and recording of time/temperature conditions are applicable to other non-blood biologicals requiring refrigeration or frozen storage.

Blood Products and Plasma Derivatives

Blood banks and plasma centers typically have back-up generators and emergency procedures in place for storing products in the event of a power outage.

• Blood establishments collecting and storing blood and blood components generally have written procedures in place to address emergency circumstances. Problems or issues affecting the blood supply should be brought to the attention of the FDA.

• Blood establishments should contact their Consumer Safety Officers if they need assistance with handling products impacted by power failures.

• Blood components exposed to flood waters should be discarded.

For health clinics, physician offices or in-home users that may not have emergency back-up power, the following may be helpful:

• There is some evidence that lyophilized coagulation products such as Factor VIII and Factor IX may be stored at room temperature for a fairly long period of time without loss of factor potency. If you are concerned about the exposure or efficacy of a particular product, please call the supplier or the manufacturers' customer service department.

• Many immune globulin products are licensed for storage at 36 to 46 degrees Fahrenheit, and some products may be stored at room temperature for all or part of the time before expiration. Because storage temperatures and times are specific to each product, you should follow the package insert recommendations for Immune Globulin Intravenous (IGIV), intramuscular IG (IG), and subcutaneous IG (IGSC) products. Products requiring lower temperatures can be stored on wet ice. All of these products should not be frozen. If you have any questions about the storage of these products, you should consult the package inserts.