What is a public health crisis, and why do we have so many of them?

A night sky glowing with fire in the mountains, thousands of emergency personnel deployed, and hundreds of thousands more ordered to evacuate from their homes. A series of wildfires in Los Angeles County sparked by dry conditions and whipping Santa Ana winds is the first public health emergency declared by the Department of Health and Human Services for 2025—but, it almost certainly will not be the last.

The severity of public health emergencies is increasing, fueled by contagious disease threats, natural disasters, and human-made catastrophes like opioid abuse. In 2024 alone, the U.S. faced 17 public health emergencies and at least three public health advisories that made the news and elevated scrutiny about these issues—but the difference between the two can be unclear.

Northwell Health partnered with Stacker to analyze federal resources and credible news accounts to explain how government health crisis declarations work and their purpose.

Governments use declarations and advisories to alert people about public health emergencies and crises. But, the response and enforcement of these crises vary.

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What constitutes a public health emergency, and what happens when it's declared?

PHEs are defined by complex or difficult situations that impact the population's health and health systems in one or more geographic regions. They may be emergencies that begin in one place and spread globally.

From 2005 until 2024, 155 national or state public health emergencies have been declared or extended. PHEs stay active either for the duration of the event or for 90 days but can be extended. About 42% of them were for 23 separate hurricanes, followed by the national opioid public health emergency, which was extended 29 times as of the end of 2024.

It doesn't need to be a pending catastrophic disaster to be declared. Before President Barack Obama's inauguration, President George W. Bush declared a PHE to call upon more resources to keep attendees safe, anticipating large crowds for the pivotal moment in American history.

The secretary of health and human services makes PHE declarations, which can be activated if an emergency is imminent and has the potential to significantly impact national security or the health of U.S. citizens.

Once the Department of Health and Human Services issues a PHE declaration, it must inform many government agencies, including Congress, the Department of Homeland Security, the Department of Justice, and the FBI. Then, government agencies can mobilize resources like funding and personnel to implement emergency response measures that may include waiving regulations to speed up responsiveness or conduct investigations into the origins of the emergency.

In certain instances, such as in response to Hurricane Helene in 2024, once the president issues an emergency declaration and the HHS secretary declares a PHE, Medicare and Medicaid providers and suppliers are given greater flexibility to support the emergency health needs of their beneficiaries. For Hurricane Helene, the Administration for Strategic Preparedness and Response also deployed personnel to assess the storm's impact and provide medical care.

The ASPR coordinates the logistics of the federal response and helps states by providing funding and technical assistance when necessary. Its powers grew in 2022 as a counterpart to the Centers for Disease Control and Prevention, the Food and Drug Administration, and the National Institutes of Health.

Public health advisories are the surgeon general's priorities

Not to be confused with PHEs, "public health advisories" function differently—and are more like a wake-up call—with a less straightforward approach.

Public health advisories are called for by the surgeon general, who issues these statements to educate and raise awareness of significant and urgent public health issues. Advisories also advocate for short- and long-term solutions to address these issues by individuals, health care providers, and policymakers. However, they do not have the authority to enforce policy or activate funding. They are generally shorter and more urgent than full surgeon general reports, but they can have a significant impact.

A 1964 report on the health risks of smoking kick-started a spate of efforts from across society—governments, private sector actors, and volunteer organizations—to combat its adverse effects. It helped start conversations about such ambitious projects as cigarette tax increases and smoke-free air laws. Taken together, these concerted efforts have extended the lives of an estimated 8 million Americans, according to a study published in the Journal of the American Medical Association.

Surgeon General Dr. Vivek Murthy has issued a range of advisories, most recently on how alcohol increases cancer risks and the harms of gun violence—but also on the effects of social media on youth mental health within months of Meta's news-making questioning before the Senate Judiciary Committee.

Without a clear and present danger like public health emergencies, it can be difficult to figure out how seriously to take the surgeon general's advisories, some of which have been characterized as public health crises like other public health emergency declarations. In an op-ed, Jeneen Interlandi, a scientist and public health writer for The New York Times Magazine, captured the confusion of the language used to describe these, saying, "In public health, at least, there is no objective formula for determining when a problem becomes a crisis."

She points to the subjectivity of public health crises plainly: "Even a deadly disease is a crisis only when we treat it like one … keep in mind that heart disease has killed nearly 100 million people in the time it took COVID to claim 7 million or so."

Interlandi argues that framing so many issues as crises lessens its effect and can lead to apathy. "In the future, if we survive that long, historians will marvel at either our capacity to endure so much hardship at once or our ability to label so many disparate problems with the same graying word," she wrote. "In the meantime, officials and policymakers—and, yes, journalists—ought to consider how they employ this term and why, and whether it's having the desired effect."

On the other hand, these advisories send a clear warning to the public that something is amiss, especially when it's hard to parse because of its widespread effects and ubiquity. After decades of mass shootings and staggering statistics of homicide and suicide, the government finally declared gun violence—the leading cause of child deaths nationally—a public health crisis in an advisory from the U.S. surgeon general in 2024. The historic declaration outlined the severity of the public health emergency and suggested solutions to mitigate it.

High-profile actions like these turn public attention to emergencies that may be living in the shadows. Like cigarette smoking before it, millions of lives could be extended because of it. As physician Dr. Deborah Prothrow-Stith told NPR, "It is time again to treat this epidemic, reduce our rates, and stay with it," she said. "We've done it before. We can do it again."

Story editing by Carren Jao. Additional editing by Elisa Huang. Copy editing by Tim Bruns. Photo selection by Clarese Moller.

This story originally appeared on Northwell Health and was produced and distributed in partnership with Stacker Studio.