• • • • • • • • • To help prepare for public health emergencies, medical countermeasures () may be stockpiled by governments and even by some private sector partners. For example, the U.S. Department of Health and Human Services (HHS) Assistant Secretary for Preparedness and Response (ASPR) oversees the (SNS), which has large quantities of medicine and medical supplies to protect the American public if there is a public health emergency (for example, a terrorist attack, flu outbreak, or earthquake) severe enough to cause local medical supplies to run out. Some state and local governments and private sector entities also stockpile MCMs to have ready access to them if an emergency were to occur. A medical product is typically labeled by the manufacturer with an expiration date. This reflects the time period during which the product is expected to remain stable, or retain its identity, strength, quality, and purity, when it is properly stored according to its labeled storage conditions. Expiration dating can present challenges to MCM stockpilers because MCMs that have reached their labeled expiration date in most cases cannot be used.