Throughout the covid-19 pandemic, there have been fierce debates about the scope of public health and the differential utility of recommendations versus mandates. With the rapid development of highly effective vaccines against covid-19, the acute phase of the pandemic will likely end with a transition to addressing covid-19 as an endemic virus. However, the next public health emergency may not be far off, and it is important to take stock of what lessons were learned. 

Public health has traditionally operated on core principles including equity, social justice, and participation. Equity is critical since the impact of respiratory pathogens have historically been defined by socioeconomic disparities. These disparities, therefore, could have been anticipated as drivers of covid-19. Social justice suggests the need to try and achieve balance of the benefit and potential harms of an intervention to a community. And finally, participation focuses on engaging beneficiaries in the design and implementation of public health programmes.

Here, we review the experience of covid-19 and put forth 10 principles of how the public health community should manage pandemics moving forward. 

1. Resources before restrictions. In the context of a rapidly emerging public health emergency, it is natural to wish to impose restrictions in order to curb transmission. During the covid-19 pandemic, we have seen how risk of catching the virus was actually mediated by structural determinants, including living and working conditions. While it was reasonable to implement widespread restrictions early in 2020, when uncertainty was high, it is critical to accompany any restrictions with adequate resources to address unmet needs. Since essential workers, broadly defined as people who cannot work remotely, were often still asked to go to work, restrictions may have yielded limited impact unless people were provided safe isolation spaces, occupational health support including well-fit N95 masks when appropriate, core employment benefits such as paid sick leave, support for those needing to self isolate, and outreach testing aligned with lived realities.
2. Do more for those who need more. Deep inequities define many societies, so public health often designs services allocating greater investments to mitigate these structural inequities. Equitable design of testing and vaccination programmes would require more outreach-based approaches to aid people who cannot work remotely, work multiple jobs, do not have private transport, and cannot take time off work. Similarly, if people have sufficient resources, emergency financial and isolation support may not be needed to prevent household or occupational transmission. But clearly, there are many people who do need these services—and moving forward—public health can and should anticipate these unmet needs and work to address these in any pandemic response.
3. Meet people where they are. Public health is a service industry that must meet its clients where they are. This is fundamentally different to other sectors, for example, a law enforcement agency which is focused on aligning behaviors with a specific set of policies. Public health serves people as they are, whereas the police bring people to where they expect them to be. People—not experts—decide how much they are willing to give up, and what is not possible to forgo. For example, in this pandemic, we asked Americans to abandon holding the hand of a loved one as they died. That is something that will scar our souls for years to come. Was that a choice made by people—or the whims of hospital bureaucrats? We struggle with that decision and many others that appear to run counter to the will of the people or the very nature of humanity.  
4. In the beginning precaution is fine, but eventually public health must be driven by data. The precautionary principle—when you don’t know, be careful—is a commonly used framework in public health. During covid-19, this principle was often used to proactively close establishments without characterising the contribution of those closures to overall transmission. But precaution is not an absolute, nor an indefinite, mandate. It is a renewable contract. As more information comes out, such precautions must be revisited and altered. Temperature screens, plexiglass shields, mask wearing outside, closing schools, not allowing small outside gatherings—all interventions driven by assumptions that should have been continually revisited as the data was garnered that such practices did not affect epidemic trajectories.Schools represent an example of the challenges of empiricism during covid-19 with often blanket closures. Could schools be opened safely? In the US, we did not try until the fall of 2020, and even then, although schools opened safely and data were presented, these results were not believed by many. There are some questions for which we continue to lack good data: for instance, whether 2-4 year old children need masks—a decision that splits the World Health Organization (WHO) and Centre for Disease Control and Prevention (CDC) guidance. Public health programmes should continually strive for empiricism—and sustained use of restrictive strategies without attempts to reduce uncertainty is bad policy.
5. Debate and dialogue. Nothing about the epidemiology or appropriate responses to covid-19 has been simple. Consequently, perspectives have varied even among highly trained and experienced professionals systematically evaluating the same data. Engaging in discussions about the validity of complementary or even contradictory inferences can support an effective response. However, it is not feasible to engage meaningfully within 280 characters or if value judgments are ascribed to only certain positions. Public health means that the consensus view may have blindspots, so we must encourage healthy debate and dialogue. Debate was stifled during covid-19 in the name of fear. We witnessed social media platforms censoring scientific views and positions, only later to rescind those bans (e.g. the lab leak hypothesis). But equally we have seen misinformation proliferate on social media platforms. How to manage, foster, and regulate social media businesses must be part of future disaster planning.
6. Duty and sacrifice. Our parents’ generation were willing to die for their country, and yet—in modern America—we seem less and less able to even tolerate a minor inconvenience. Duty is intrinsic to public health, and has always meant caring for the vulnerable, even when that puts yourself at risk, or provides no accolades or glory. Earning money from lucrative consulting (which has happened too often by public health or epidemiologic experts in this pandemic) is not public health, but a cancer on our soul.
7. Speaking truth to power. Public health means going on TV and saying that the Governor is failing, not that people are failing. Yet, over and over, we heard experts lament that it was private gatherings and bad people, and not bad systems and weak leadership that failed. The inattention to the structural and network risks including structural racism that increased risks for some and not others is antithetical to public health. Shame-based messaging has no role in a pandemic.
8. Specified interventions without judgement. Historically, public health tries to disrupt normal life—and culture—as little as possible while still preserving safety. Public health does not seek to change the way of life of the populations on which it serves. Public health does not judge or shame people for the desires of the body or spirit, such as being around others.
9. Does not know borders. Public health does not divide us, and consider others foreign or alien. It unites us. Just as covid-19 does not follow political maps, public health spans all nations. The combination of inequitable distribution of vaccines around the world, combined with differential freedom of movement based on vaccination status allows public health to validate xenophobic policies. The covid-19 response highlighted nationalistic tendencies across much of Europe and North America which should be understood to better facilitate future coordination across nations.
10. Harm reduction: Harm reduction—when applied to disease prevention including for infectious diseases—is the principle of advising individuals how to mitigate risk, while acknowledging the real-world human desires or conditions that may lead individuals to take some risks. The goal of harm reduction is similar to lockdowns—reducing infections. However, harm reduction-based approaches acknowledge and integrate realistic strategies responsive to the needs (financial and social) of human beings.

These debates have increasingly been tied to political parties. Restrictions on movement or business, and the use of various non-pharmacologic interventions for covid-19, are increasingly seen as markers of being on the political left or right. Sometimes, and perhaps even worse, they take on moral dimensions. Even something universally seen as a good—public education—has become linked to party. While politics will always contextualize public health, empiricism is unattainable if every decision in public health is viewed through a political lens.

The world continues to be more connected, facilitating both the best and worst of human experiences. From the perspective of infectious disease pandemics, it means that the emergence of a highly transmissible virus runs the risk of rapid global spread. Pandemic preparedness is more than data aggregators and rapid vaccine development, it is about leveraging the best of public health principles to support evidence-based and human-rights affirming responses to serve all, not just the wealthy. 

Monica Gandhi, infectious diseases doctor and professor of Medicine at University of California San Francisco. Twitter: @MonicaGandhi9

Vinay Prasad is a practicing hematologist-oncologist and an associate professor in the Department of Medicine and the Department of Epidemiology and Biostatistics at University of California, San Francisco. He tweets @VPrasadMDMPH

Stefan Baral is a physician epidemiologist and an associate professor in the Department of Epidemiology at the Johns Hopkins School of Public Health. He tweets @SDBaral

Competing interests: The authors have read and understood BMJ policy on declaration of interests and declare the following interests: VP discloses research funding from Arnold Ventures; royalties from Johns Hopkins Press, Medscape, and MedPage; consulting fees from UnitedHealthcare; speaking fees from Evicore and New Century Health; and Patreon backers for Plenary Session podcast.