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As of this writing, there have been 127,863 confirmed cases and 4,718 deaths from the COVID-19 pandemic worldwide.

In the U.S., there have been over 1,200 cases and 38 deaths. In three short months, a novel coronavirus has captured global consciousness and changed day-to-day life in large parts of the world, in the process becoming a public health emergency that is testing, like perhaps no event before it, our global capacity to respond to large-scale infectious threats.

As public health agencies like the World Health Organization (WHO) and the Centers for Disease Control and Prevention (CDC) work around the clock to coordinate a local, national, and global response to the rapidly changing situation, we are, collectively, learning how to better grapple with this epidemic.

While there will be much to learn when (we hope) this epidemic is over, I think there are some key lessons that emerge clearly that are worth highlighting even now, when the epidemic is at the very forefront, dominating all our conversations, sharpening our thinking.

Lesson one: public health is political

It is difficult to find any discussion about COVID-19 that does not mention the actions of a government—whether it is the Chinese government’s handling of disease containment or the American government’s efforts to keep COVID-19 from spreading to its shores.

When large-scale, sudden health challenges strike, political leadership is essential for coordinating response and communicating to the public accurate, up-to-date information about the threat. It is on the latter point, especially, that the Trump administration has struggled. The president has contradicted CDC officials, mischaracterized the nature of the threat, and attempted to portray virus fears as a hoax by political opponents.

These actions do not help efforts to stop this outbreak. In fact, they hinder them, by muddying the waters when clear communication can mean the difference between sickness and health, life, and death.

The Trump administration has also cut critical public health programs created to protect populations during disease outbreaks, further undermining response.

In addition to coordinating public health response and controlling the budget of key health organizations, politics shapes health at a fundamental level, influencing the social, economic, and environmental conditions that create a context for health or disease.

COVID-19 has exposed just how lacking investment in improving these conditions has long been in the US. We have not done enough to prevent pockets of marginalization from emerging within the broader population. This has increased certain groups’ vulnerability to COVID-19—older adults, in particular, and those living with underlying chronic disease.

The choice to help or ignore such populations is deeply political, and it extends to other groups facing marginalization, from LGBT populations, to immigrants, to people of color. There is ample research showing how the conditions of marginalization undermine health.

For example, laws allowing businesses to deny services to same-sex couples have been linked to a 46 percent increase in mental distress among sexual minority adults. Socioeconomic status is one of the key drivers of health, and this status is inseparable from the world of politics.

Lesson two: science matters

In this age of “fake news” and “alternative facts,” it is possible to think science is somehow less relevant than it once was.

Denial of climate change and the safety of vaccines are examples of how science can be pushed aside when it conflicts with a political agenda. President Trump’s dim view of health authorities is another reflection of this anti-science trend.

Yet science matters. This is especially clear during a disease outbreak. For example, social distancing—the practice of preventing the spread of disease by limiting the interaction of individuals and groups—may seem like an obvious action to take during outbreaks of disease.

But there is much we are still learning about the science of why and how social distancing works. Research like this study of social distancing during the 1918—1919 flu pandemic helps inform our understanding of the efficacy of this approach. The study found a strong link between “early, sustained, and layered application” of measures such as school closures and bans on public gatherings and mitigating the effects of the pandemic.

Such research is just as important to pandemic response as the science of vaccines, helping us chart a course through shifting circumstances. It is important to listen to what science tells us—not just about responding to COVID-19, but about what we can do to build a healthier world every day.

Lesson three: education of the public matters

Infectious challenges shine a light on a central concern of public health: that it is about public health—about improving the health of populations. This is not what we tend to think about when we think about health in this country.

Instead, we think about the health of individuals, of the doctors and medicines that help us recover when we, as individuals, get sick. We do this instead of thinking about the public health steps we should take to prevent disease in populations—to keep from needing doctors and medicines to begin with.

Preventing disease in populations takes robust, responsive health systems, cities and communal spaces that are built with health in mind, economies that do not generate the poverty and income instability that feed poor health, and cooperation at the local, national, and global level in creating the conditions for health.

All of this requires long-term planning, and a willingness to invest in health as a public good worthy of collective by-in. This begins with educating the public about what really matters for health. The reaction to Covid-19 has shown how much we still must do in this regard.

In the weeks since the disease was first directed in Wuhan, Hubei, China, anti-Chinese sentiment has been part of the narrative about Covid-19. This is not only unfortunate in itself, it undermines our ability to address the disease. Navigating infectious threats—and promoting public health in general—depends on our ability to work together, which we cannot do if we are willing to tolerate marginalization, bigotry, and the reflexive building of walls.

Lesson four: we should always be talking about public health

In the film Glengarry Glen Ross, there is a famous scene where a character tells a group of salesmen that the key to their profession is “ABC,” or “Always Be Closing.”

The key to a healthier world, where we are far less vulnerable to infectious threats, could be said to be “ABTAPH,” or “Always Be Talking About Public Health.” This means talking about public health not just in times of challenge, but at all times.

Imagine, for a moment, what our country would be like if we placed a concern for public health at the heart of all we do. If we poured money into the public health programs the Trump administration has cut. If we refused to accept certain groups facing disproportionate vulnerability to disease, understanding that their vulnerability is our vulnerability, especially during an epidemic.

COVID-19 is a novel challenge, but it is not the first large-scale health threat to show us why we need to make this better world a reality. The destructive hurricanes of recent years are another warning of how disasters can be far worse when we neglect public health.

When hurricanes strike, a population’s ability to “bounce back” is shaped by the conditions that influence public health in a region prior to the disaster. For example, a 2010 study found that poverty, housing, and immigrant and minority status all played a role in creating vulnerability among populations prior to Hurricane Katrina, and increased the potential for suffering after the storm.

When hurricanes strike, we are quick to mobilize aid for the affected, just as we demand rapid response from government and health authorities in the event of a disease outbreak. Yet, in both cases, we are less likely to address the “preexisting conditions” that can worsen these acute challenges. Disasters happen. We need to have the public health infrastructure in place so that, when they do, their effect is as minimal as we can make it.

COVID-19 has revealed weak points in how we think about health and how we prepare for disease. Many questions about COVID-19 remain. Perhaps the most important one is: can we engage in the uncomfortable conversations we need to have that can lead to a healthier world?

It is only by having these conversations, and by learning the lessons of challenges like COVID-19, that we can build a world that is less vulnerable to challenges like what we now face.

Sandro Galea, MD, DrPH, is Professor and Dean at the Boston University School of Public Health. His latest book is Pained: Uncomfortable conversations about the public’s health. Follow him on Twitter: @sandrogalea