States have taken wildly different approaches to vaccine distribution, but one thing unites them: many of their most at-risk residents, particularly in communities of colour, are being left behind. In Connecticut, which boasts one of the best coverage rates in the country, the share of the White population inoculated is at least twice that of the state's Black population. In North Dakota, another supposed success story, the gap is starker — the share of White residents who have received at least one dose is more than three times that of Black residents.This pattern holds for every state providing data.

This doesn't just cost lives. It also undermines our ability to achieve herd immunity, the point at which enough people are vaccinated to provide protection for a whole community. Although states can pad early vaccination rates by focusing on those willing and able to sign up and transport themselves to a clinic, this merely defers the difficult task of reaching places that have been historically left behind — where barriers to healthcare access didn't start with the coronavirus. If governments don't change their strategies now, vaccination rates will plateau, and large pockets of the country will remain vulnerable, offering a refuge for the virus and for the evolution of new variants. This will only extend the pain and suffering this plague has already caused and leave us more susceptible to new outbreaks.

Well before the first vaccines received Food and Drug Administration authorisation, scientists understood that speed and breadth of inoculation were equally important. They recommended a nuanced plan that prioritised distribution to those at highest risk of death and serious complications. Covid-19, the disease caused by the novel coronavirus, has a disproportionate impact on the elderly but also on people of colour, not only because they are more likely to have jobs that leave them exposed but also because of factors such as underlying disease burden and poor healthcare resulting from decades of health inequity.

But almost as soon as the shambolic rollout began, a new drumbeat emerged: "Get shots into arms."

Stories of long lines in freezing weather, doctors making mad dashes in the night to deliver expiring doses, and elderly parents spending hours on broken registration websites fuelled arguments that excessive concern with equity was generating complexity and slowing us down. Of course, this was all predictable. We did not enter the pandemic with well-resourced or integrated public-health systems, and the Federal Government under the previous administration failed to adequately plan for anything beyond the development of the vaccines themselves. But, rather than address those realities head-on, some states, encouraged by the Trump Administration, began giving up and pivoting to a stripped-down strategy of first-come-first-served within broad, age-based categories.

That approach can still reach those most at risk, including people of colour, but only if it is accompanied by a robust, fully funded plan for serving hard-to-reach groups. Some localities have taken steps in this direction. In Washington, for example, city officials changed the vaccine registration system to give priority to seniors in poorer areas with more Black residents after more than 70 per cent of the first week's shots went to wealthier, Whiter wards. Yet, nationwide, that is not what we are seeing, even under a new president who extols the need for equity. The Biden Administration has decided to ship vaccines to thousands of chain pharmacies such as CVS, Walgreens, Kroger and Walmart — a plan that will bring their shareholders billions in profits — yet only 250 community health centres. This is happening despite early evidence that chain pharmacies have been less effective than their smaller counterparts.

Many states have followed similar paths, distributing only a small fraction of doses to community health centres or cutting out local clinics entirely. And even if such clinics get additional doses, they will need significantly more logistical support to distribute them efficiently. State and local health departments, too, are seriously and chronically underfunded. The result is that we are underinvesting in essential equity measures just as they are needed most. We are sending the least privileged — those who lack ready access to healthcare or the resources to spend all day online to book an appointment — to the back of the line.

The truth is that reaching herd immunity and protecting the vulnerable are inseparable goals. Achieving both requires tailored outreach to combat vaccine hesitancy among those affected by a history of medical experimentation, who lack access to primary care, who do not speak English or who are at risk because of their undocumented status. It demands setting up distribution sites in "pharmacy deserts" and rural areas, using mobile teams to get shots to those who are stuck at home, and regularly sending doses to the thousands of local clinics where many minority and low-income Americans receive care. We also need racial and ethnic vaccination data down to the census tract level. While two thirds of the states are tracking disparities in some way, we need all states to do it consistently and at a level of geographical resolution that allows specific targeting of efforts to fairly distribute the vaccine. Ignoring equity will leave our job half-finished. A pandemic is like a forest fire: leaving embers just risks the coronavirus, or its new variants, roaring back from these forgotten places.

One reason communities of colour have been left behind is concern that some ways of reaching them could run afoul of the law. The Supreme Court has, for example, struck down certain uses of race in the context of education and employment. In December, Oregon paused a programme that sent coronavirus relief funds to Black residents and Black-owned businesses pending a lower-court decision in a suit alleging that doing so violates the Constitution's equal-protection clause. Directly assigning doses to individuals based on race would face serious obstacles in the courts, but the commonsense measures outlined earlier are a different matter. For example, courts uniformly agree that the Government may collect and study demographic data regarding race. And while the details matter, there are many things states can do: for example, targeting based on categories other than race — say, by geographic area, income or language — and understanding race holistically as one among many factors to help these groups. States should not be designing and building discriminatory systems out of fear of legal challenges.

The coronavirus relief Bill working its way through Congress may finally provide significant funding for states and localities to do this right. But if we do not begin today designing appropriate programmes, we will lose precious months. Full vaccination coverage in the United States requires tailoring our plans to communities with different needs; some require additional attention to address unique barriers. If we pretend that glaring differences in access do not exist, we will delay our nation's recovery from this pandemic. None of us is safe from the coronavirus until we're all safe.

• Gregg Gonsalves is an assistant professor in the epidemiology of microbial diseases at the Yale School of Public Health, an associate professor of law at Yale Law School and a co-director of the Global Health Justice Partnership. Amy Kapczynski, a professor of law at Yale Law School, is a co-director of the Law and Political Economy Project and the Yale Global Health Justice Partnership. David Herman is a student at Yale Law School and a member of the Global Health Justice Partnership