A public health emergency is a formal declaration by a government official or international body that a disease outbreak, disaster, or other health threat has reached a level of severity requiring extraordinary response measures. These declarations unlock funding, relax regulatory barriers, and activate resources that aren’t available under normal circumstances. They exist at every level of government, from local and state declarations up to national emergencies and global alerts issued by the World Health Organization.
How a National Emergency Is Declared
In the United States, the Secretary of Health and Human Services has the authority to declare a public health emergency under federal law. Once declared, the emergency lasts for 90 days and terminates either when the Secretary determines the threat no longer exists or when that 90-day window expires, whichever comes first. The declaration can be renewed in additional 90-day periods if the threat persists, which is exactly what happened during COVID-19, when the emergency was renewed repeatedly for over three years.
The declaration gives the federal government a broad set of tools. The Secretary can issue grants, fund investigations into the cause and treatment of a disease, and enter into emergency contracts. Federal agencies can extend deadlines for required data submissions and waive associated penalties. If a state governor or tribal organization requests it, the Secretary can authorize the temporary reassignment of public health workers to address the crisis. The government can also fast-track hiring, bypassing the usual civil service procedures to fill critical positions during the response.
What Changes for the Public
The practical effects of a public health emergency touch everyday life in ways most people don’t expect until they experience one. During COVID-19, Congress required states to maintain Medicaid enrollment for nearly all beneficiaries as a condition of receiving a temporary 6.2 percentage point increase in federal Medicaid funding. This “continuous enrollment condition” meant states could not drop people from Medicaid coverage during the emergency period. When that provision ended on March 31, 2023, millions of people faced eligibility redeterminations for the first time in years.
Healthcare delivery rules also shift dramatically. Telehealth is a clear example. Before COVID-19, Medicare placed strict limits on which patients could use telehealth, where they had to be located, and which providers could offer it. The emergency declaration allowed those restrictions to be waived. Patients could see doctors by video or phone from home regardless of where they lived. Many of those flexibilities have since been extended by legislation through December 31, 2027, and some, particularly for behavioral and mental health services, have been made permanent. Audio-only phone appointments, for instance, are now a lasting option for Medicare patients receiving mental health care.
How State Emergencies Work
State governors have their own parallel authority to declare emergencies, and these declarations come with significant powers. A governor can suspend specific provisions of state laws, local ordinances, and regulations if following those rules would prevent, hinder, or delay the emergency response. These suspensions are issued in 30-day periods and can be renewed, but they must represent the “minimum deviation” from existing law necessary to address the crisis.
In practice, this might mean suspending licensing requirements so out-of-state healthcare workers can treat patients, waiving procurement rules so the state can buy emergency supplies quickly, or modifying scope-of-practice laws so pharmacists or nurses can administer vaccines without the usual paperwork. Each suspension must specify exactly which law is being changed and under what conditions, and it must be tied directly to the emergency response rather than used as a blanket override of normal governance.
The International Level: PHEIC
At the global scale, the World Health Organization can declare a Public Health Emergency of International Concern, known by the acronym PHEIC (pronounced “fake”). This is the highest level of alarm the WHO can issue, and it’s governed by the International Health Regulations adopted in 2005. A situation qualifies as a PHEIC if it meets at least two of four criteria: the public health impact is serious, the event is unusual or unexpected, there is significant risk of international spread, and there is significant risk of international travel or trade restrictions.
The WHO Director-General makes the final call, but not alone. An Emergency Committee composed of international experts drawn from fields like disease control, virology, vaccine development, and infectious disease epidemiology reviews the evidence and advises on whether the situation warrants a declaration. At least one committee member must be an expert nominated by the country where the outbreak originated. The committee also recommends temporary measures that affected countries and other nations should take to contain the spread while avoiding unnecessary disruption to trade and travel.
Once declared, a PHEIC doesn’t simply remain in place indefinitely. The Emergency Committee reconvenes at least every three months to reassess the situation, reviewing current data to determine whether the emergency still qualifies and whether the recommended measures need to change. Notable PHEICs have included the 2009 H1N1 influenza pandemic, the 2014-2016 West Africa Ebola outbreak, the 2015-2016 Zika virus outbreak, COVID-19, and mpox.
What Gets Activated Behind the Scenes
One of the most tangible assets triggered by a federal emergency declaration is the Strategic National Stockpile, a federal reserve of medicines, medical equipment, and supplies maintained for a range of health threats. When an emergency is declared, these materials can be deployed to affected areas to supplement state and local supplies that are running low or exhausted.
Emergency declarations also open the door to what legal scholars describe as “unconventional legal responses.” This includes mechanisms to help government agencies quickly acquire supplies, bring in volunteer health workers to handle the surge in patients, and coordinate across jurisdictions that normally operate independently. The legal landscape during an emergency is deliberately flexible, designed to remove bureaucratic bottlenecks that would slow down a response when speed matters most.
How Emergencies End
Ending a public health emergency is not simply about the disease disappearing. At the federal level, the HHS Secretary formally declares that the emergency no longer exists, or the 90-day period expires without renewal. The consequences of ending an emergency can be just as significant as declaring one. Waivers expire, funding streams close, and regulatory flexibilities that patients and providers have come to rely on revert to their pre-emergency status unless Congress acts to extend them.
At the WHO level, the Emergency Committee advises the Director-General on when to terminate a PHEIC, based on whether the epidemiological situation still meets the criteria. The COVID-19 PHEIC, for example, lasted from January 2020 to May 2023. When that designation ended, countries were expected to transition from emergency response to longer-term disease management, integrating surveillance and vaccination into routine public health systems rather than relying on emergency-level coordination.