COVID vaccines were developed with record-breaking speed. But their distribution has been anything but quick. As of Monday morning, about 47 percent of the doses distributed to states had not been administered, according to data from the U.S. Centers for Disease Control and Prevention. This means that a month into the distribution effort, only about 6 percent of people in the U.S. have received at least one dose of the two-dose vaccines that are now available. Anthony Fauci, the nation’s top infectious diseases expert, estimates that up to 90 percent of the U.S. population needs to be vaccinated to reach herd immunity—the point at which so many people are protected from the disease that it peters out.

In an effort to pick up the pace, many states have expanded access to a COVID vaccine to everyone aged 65 and older, people with medical conditions that put them at high risk of the disease and certain essential workers. But the hodgepodge of policies and priorities in different states and the lack of unified infrastructure has caused chaos and confusion for people eager to get their shot. Many of the country’s most vulnerable people are encountering busy phone lines, crashing Web sites, byzantine online registration portals and long lines at vaccination sites, prompting concerns that the expanded rollout could worsen the racial and economic inequalities laid bare by the COVID-19 pandemic.

Emergency physician and former Baltimore health commissioner Leana Wen has been vocal about the tough decisions that must be made to address this distribution debacle. Wen spoke with Scientific American about how authorities decide who is next in line, the hurdles in getting vaccinated that some people are facing and the need to balance speed with fairness.

[An edited transcript of the interview follows.]

How do we decide who to prioritize for vaccines? And how does the ethics of who is “deserving” play into that process?

The CDC has an advisory committee that took painstaking approaches to determine the priority tiers. The determination of who went first—health care workers and nursing home residents—was fairly uncontroversial. Beyond that, I think it gets to the question you are asking, which is not necessarily who is “deserving” but rather what problems we are trying to solve. Is it most important to safeguard those who don’t have the option to social distance? Or is it more important to reduce illness? I don’t have an answer here, but the way the vaccine rollout has been going so far is not working. The tiers look good on paper, but they are so rigid. And there are so many problems with matching supply and demand on the ground that the lack of flexibility has resulted in the great tragedy of doses being wasted. At this point, the necessary step is to relax the measures and open vaccination up to broader categories of eligibility because there has been a lack of infrastructure to implement this the right way.

Why is the vaccine distribution going so poorly?

It’s a combination of two things that are interrelated. One is that the federal government seems to have understood its role in the vaccine process as stopping at the point at which it gets vaccines distributed to states. I don’t think this was apparent before, but it certainly is now. [The federal government] entirely ceded the responsibility of the “last mile,” so to speak. The second related issue is that the state and local health departments put in charge of this last mile have not had the funding that they need. State and local health departments were already substantially underfunded and understaffed even before the pandemic. And then they had to take on testing, contact tracing, public education, and helping businesses and schools to reopen safely with a very limited budget. Now they’re being told to stand up this vaccination program without additional staff or additional resources. I heard a health official liken this to being given brand-new shiny vehicles but with no gas. State health departments requested $8.4 billion, but [at first] only received $400 million. [Editor’s Note: The most recent $900-billion COVID relief bill included the remaining $8 billion in funding for vaccine distribution.]

Is the public vaccine rollout making it difficult for people who might not have a lot of resources or the wherewithal to navigate all the red tape?

As we move on to vaccinate as many people as we can, those who are already disadvantaged and those who are already the most vulnerable will have less access again. The people who are wealthier and privileged—those who can keep calling a hotline because they have a cell phone with unlimited minutes or can figure out how to sign up online because they have good Internet and are tech-savvy—will have an advantage. If you make it first come, first served, you will vaccinate more people, but it will come at the cost of not prioritizing fairness. There are no clear answers. I think you need to keep on looking toward fairness and equity. But that really should not come at the cost of speed either. How you balance those is extremely tricky.

Is it fair to open up eligibility so widely, when so many people at high risk still have not been vaccinated?

You have to consider a balance of fairness versus speed. If fairness is the overriding principle, then it will be slower because it will take time to reach individuals who don’t have much access or resources or might be vaccine-hesitant. But there’s definitely an argument to be made at this point in the pandemic—when thousands of people are dying every day—that speed is paramount. All the individuals who are vaccinated were once susceptible to coronavirus, so every dose that you’re getting into an arm is necessary and will help.

But how do you address those concerns without further exacerbating the inequalities so clearly exposed by the pandemic?

It may be that we get out the doses as quickly as we can in this first tranche while we’re building the infrastructure to reach these hard-to-reach and more vulnerable communities. I think there is a way to do both. But there needs to be some acknowledgment that some trade-off has to occur.

Do you think these logistics hurdles will get better or worse going forward? Will distribution get even trickier as more people become eligible?

The hope when these tiers were very carefully designed was that people would have some sense of when it’s their turn. If we had a functional system, then, in theory, you would enter in your information, find out when you would likely be eligible to get vaccinated, and then get an e-mail or a call at that time. But we don’t have anything close to a system like this for something that is in such high demand. I think the next best thing is to open it up to a lot more people, and that includes creating community access points. Offer the vaccine at doctor’s offices, pharmacies, grocery stores, mass vaccination sites. Will it be confusing? Absolutely, because each state will still have its own rules. And it will lead to that first come, first served mentality. But it will be better than the other scenario, which is letting a whole lot of vaccine go to waste.

How urgent is this issue?

This is a race against time. We need to get out the vaccine in order to reach herd immunity. We know this virus—like every virus—is constantly mutating. We are already seeing the B.1.1.7 variant first identified in the U.K. and the B.1.351 variant first identified in South Africa, which are more transmissible. There may well be home-grown U.S. variants that we find over time that are not only more transmissible but also more virulent and cause more severe disease. [Editor’s Note: As of this writing, another variant called L452R, which was first detected in Denmark, has been linked to several outbreaks in California, but it is not yet known whether it is more contagious or virulent.]

Imagine if this pandemic were a war against a foreign enemy where 3,000 to 4,000 Americans were dying every day. We wouldn’t even question the idea of devoting all our resources to this effort. That’s what should be happening now. [Many] Americans have not done the other measures that are needed. We’ve squandered all our other chances. The vaccines are our last best hope.

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