Ever since the new coronavirus emerged as a global threat, public health officials have repeated the same warning: Shutdowns, masks, and social distancing can help to contain the virus—but the pandemic won't truly end until we get a vaccine.

But what does it mean to "get a vaccine"?

It's not enough, after all, to devise a single dose of vaccine in a hermetically sealed laboratory. We must also conduct clinical trials to prove that vaccine is effective, manufacture it in mind-boggling quantities under impeccably sanitary conditions, dispense it into hundreds of millions of vials, ship it (perhaps under refrigeration) to every city and village in the country, and inject it into the arms of nearly every single American.

And if the vaccine requires multiple doses? Well, we'll have to do much of that work all over again.

A slip-up at any of these stages could delay the end of the epidemic, potentially costing tens of thousands of lives—and further postponing the day when America returns to "normal."

So which obstacles are most likely to delay a Covid-19 vaccine, and how can we prepare to overcome them? That's the focus of an extensive new report authored by Ezekiel Emanuel, the prominent bioethicist and former adviser to President Barack Obama, and Topher Spiro of the left-leaning Center for American Progress.

It's a sobering read, one that makes clear just how daunting a task it will be to bring this epidemic to a close.

The biggest obstacles standing in the way of a vaccine

Emanuel and Spiro identified no fewer than 22 roadblocks to a vaccine, surfacing seemingly esoteric issues such as limits in "the capacity of manufacturers of brewing equipment" and "assess[ing] alternatives to glass vials."

But upon deeper review, six potential problems stand out to us as especially critical:

1. America is investing heavily in unproven vaccine types—raising the risk that all of our major vaccine candidates could fail Most vaccines approved for other diseases are based either on live, weakened copies of the virus or "inactivated" copies of the virus. Yet many of the Covid-19 vaccines currently furthest into development, including all five vaccines prioritized by the White House's Operation Warp Speed, rely on newer, less-tested technologies, such as mRNA or viral vectors. As the report notes, "Remarkably, no U.S. vaccine uses traditional inactivated-virus technology, and only one Operation Warp Speed vaccine uses traditional protein-based technology." If these new technologies fail, the United States could be left with no effective Covid-19 vaccine—and no clear backup plan. To avert that outcome, the authors recommend diversifying the vaccine pipeline. This would not only increase our odds of finding a successful vaccine; it also could help us generate multiple vaccines, some of which could be safer or more effective for particular patient populations.
2. We'll need to manufacture perhaps half a billion doses of a vaccine That means half a billion vials to store it, half a billion stoppers to close those vials, and half a billion syringes to administer it, not to mention the supplies and technology to store and ship those doses in sterile, temperature-controlled conditions. The complexities and interdependencies in the vaccine supply chain call to mind the still-stalled supply chain for Covid-19 tests. In many parts of the country, patients can now get "tested," insofar as technicians can stick swabs up their noses, but labs don't actually have the reagents and other raw materials needed to process those swabs, leading to weeks-long delays in reporting results. To address this challenge, Emanuel and Spiro propose big investments in manufacturing facilities—not just for the vaccine itself, but also for the supplies required to package, transport, and deliver a vaccine. They also propose coordinating pharmaceutical companies, governments, and contract development and manufacturing organizations to prevent bottlenecks.
3. We'll need fair, transparent principles for distributing a vaccine once it's available Should health care workers have early access to an approved vaccine? What about people in regions of the country where the virus is running rampant? Or members of disadvantaged populations who are currently dying at disproportionate rates? So far, these questions don't have clear answers. (This challenge once again echoes controversies related to Covid-19 tests, which remain unavailable to many ordinary Americans—even as they're readily accessible to many professional athletes and high-level political leaders.) Emanuel and Spiro propose a four-tier framework for how to distribute and allocate vaccines to different populations: health care workers in tier one, essential workers in tier two, high-risk populations in tier three, and the general population in tier four. They also propose providing the vaccine to states in proportion to their populations, and making the vaccine available only at sites that can implement the targeting guidance.
4. We'll need to distribute the vaccine to everyone, including people who can't afford to pay for it To finance the vaccine itself, the authors propose a straightforward solution: universal public financing. This approach, they say, would increase uptake, avoid gaps in insurance coverage, and "eliminate profiteering." But the authors stop short of proposing how to decide which vaccines the government should pay for, or at what rates. It's not clear whether Emanuel and Spiro support value-based approaches, such as paying more for a vaccine that works more effectively—or how they'd alter vaccine prices as new evidence becomes available. And it's not clear how pricing would differ for vaccines that received significant federal funding during the development process. As for administering the vaccine, Emanuel and Spiro call on lawmakers to cap administration fees, require insurance plans to fully cover the cost, and set aside public funding to vaccinate uninsured individuals. They also propose creating public-private partnerships with retail pharmacies, such as Walmart and CVS, to establish free community vaccination clinics.
5. We'll need a comprehensive, media-savvy vaccine education campaign This is especially true because so many Americans are "vaccine-hesitant." Surveys have indicated that only about half of the population currently says they're willing to receive a Covid-19 vaccine. The authors propose widespread education campaigns using celebrities, public figures, and medical organizations. Their historical example of a successful campaign? Elvis Presley receiving a polio shot on The Ed Sullivan Show, helping to drive a massive increase in youth vaccination rates. One challenge the authors don't address: how to customize outreach to different demographic groups, which may have different levels of health literacy and trust of our health care system. They also don't provide recommendations for addressing misinformation on social media platforms, such as Facebook and Twitter.
6. Even after vaccines are administered, we'll need comprehensive reporting and disclosure The authors call for CDC to leverage its centralized distribution mechanisms for publicly financed vaccines to collect data about vaccine distribution and use, potential adverse events, and potential corruption or undue influence. This is especially critical because the FDA could preliminarily approve a vaccine on the condition that the manufacturer continue to gather further evidence. Ongoing data collection will provide essential insights into how vaccines work in real-world circumstances, such as whether a vaccine is causing unexpected side effects or diminishing in effectiveness over time. If multiple vaccines are approved, comprehensive reporting also could reveal which vaccines work best for which patients, enabling better distribution and targeting.

How Covid-19 is disrupting your supply chain (and what to do about it)

Why this matters: Getting a vaccine approved is only 'the tip of the iceberg'

For those of us feeling encouraged by the recent progress of vaccine candidates, Emanuel and Spiro's report is a sobering read. It makes clear that vaccine approval is just the "tip of the iceberg," and that the real work will come next: manufacturing, distributing, publicizing, and monitoring the vaccine—that is, taking it from a few isolated laboratories into the arms of 330 million Americans.

And let's not forget, even a universally administered vaccine may not be universally effective. The FDA has said it will approve a vaccine that shows 50% efficacy relative to a placebo. While manufacturers and public health experts are aiming for higher effectiveness (Peter Marks of the Center for Biologics Evaluation and Research has proposed 70% as a goal), it's clear that early vaccines may still leave some patients vulnerable.

And all of this is unfolding against a backdrop that has revealed just how poorly prepared the health care industry is to manufacture and distribute needed supplies—from tests to drugs to personal protective equipment—at a massive scale on short notice.

Let's hope that plans such as this one can galvanize enough investment, coordination, and planning to resolve these problems and smooth our path to the "new normal."