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Your state’s Covid-19 epidemic, explained in 4 maps

These maps show how your state is doing.

The profile of a person wearing a face mask, with an American flag in the background.
A volunteer greets local residents at a food distribution center in New York City on March 18, 2020.
John Moore/Getty Images

America’s national Covid-19 epidemic continues, with the US’s daily new cases down from an early January peak but still higher than those of most developed nations — and the country recently surpassing 500,000 deaths due to the disease.

At the state level, things can look even worse than the national picture.

Public health experts look at a few markers to determine how bad things are in each state: the number of daily new cases; the infection rate, which can show how likely the virus is to spread; and the percentage of tests that come back positive, which should be low in a state with sufficient testing. Combined, these three benchmarks can tell you whether or not a state’s coronavirus outbreak is under control.

Vox’s analysis, updated weekly, shows the vast majority of states are reporting alarming trends for coronavirus cases based on these benchmarks. Only one state — Hawaii — fares well on all three metrics, suggesting the vast majority of states don’t have their outbreaks fully under control right now.

A map of states’ Covid-19 outbreaks, based on a range of metrics.

The US outbreaks are due to the failure of both the American public and the country’s leaders to take the virus seriously enough; to the extent they did, many let their guard down prematurely. With the support of former President Donald Trump, states moved to reopen — often before seeing sizable drops in daily new Covid-19 cases, and at times so quickly they weren’t able to tell whether each phase of their reopening plan was leading to too many new infections.

The public embraced the reopenings, resuming their usual day-to-day activities and often refusing to adhere to recommended precautions like physical distancing and mask-wearing.

Even as cases began to fall later in the summer, America’s overall caseload remained very high. Yet many states moved to reopen once more, with much of the public embracing the looser restrictions and subsequently going out.

It’s this mix of government withdrawal and public complacency that experts have cited in explaining why states continue to struggle with getting the coronavirus under control.

“It’s a situation that didn’t have to be,” Jaime Slaughter-Acey, an epidemiologist at the University of Minnesota, previously told me, adding, “You had opportunities to be proactive with respect to mitigating the Covid-19 pandemic and to help normalize culture to adopt practices that would stem the tide of transmissions as well as the development of Covid-19 complications. … It was not prioritized over the economy.”

The effects are felt not just in terms of more infections, critical illnesses, new chronic conditions, and deaths, but in the long-term financial impact as the economy struggles, many people still refuse to go out, and businesses resist reopening during a pandemic.

“Dead people don’t shop. They don’t spend money. They don’t invest in things,” Jade Pagkas-Bather, an expert in infectious diseases and a doctor at the University of Chicago, previously told me. “When you fail to invest in the health of your population, then there are longitudinal downstream effects.”

With a Covid-19 vaccination campaign underway, a finish line to this crisis in finally visible. But until America reaches sufficient population protection — and, preferably, herd immunity — every day the coronavirus spreads means more illnesses, hospitalizations, and deaths.

As the country works toward vaccinating everyone, the three benchmarks tracked by Vox give an idea of how each state is doing in its fight against Covid-19 in the meantime. Nationwide, it’s pretty grim.

1) Most states have too many daily new Covid-19 infections

A map of each state’s Covid-19 cases per capita.

What’s the goal? Fewer than four daily new coronavirus cases per 100,000 people per day, based on data from the Covid Tracking Project and the Census Bureau.

Which states meet the goal? Just one — Hawaii.

Why is this important? The most straightforward way to measure whether any place is experiencing a big coronavirus outbreak is to look at the number of daily new Covid-19 cases.

There’s no widely accepted metric for how many cases, exactly, is too many. But experts told me that aiming for below four daily new cases per 100,000 is generally a good idea — a level low enough that a state can say it’s starting to get significant control over the virus.

A big caveat to this metric: It’s only as good as a state’s testing. Cases can only get picked up if states are actually testing people for the virus. So if a state doesn’t have enough tests, it’s probably going to miss a lot of cases, and the reported cases won’t tell the full story. That’s why it’s important not to use this benchmark by itself, but to use it alongside metrics like the test positive rate.

The number of daily new cases may also give a delayed snapshot of a Covid-19 outbreak. If test results take a week to get reported to the state, the count for daily new cases will really reflect the state of the outbreak for the previous week.

If testing is adequate in a state, though, the toll of daily new cases is perhaps the best insight as to how big a state’s Covid-19 outbreak is.

2) The coronavirus is spreading too quickly in some states

A map of each state’s Rt.

What’s the goal? An effective reproduction number, or Rt, below 1, based on data from the Centre for Mathematical Modeling of Infectious Diseases.

Which states meet the goal? All but Alaska, Minnesota, New Hampshire, North Dakota, and Wyoming — 45 states, as well as Washington, DC.

Why is this important? The Rt measures how many people are infected by each person with Covid-19. If the Rt is 1, then an infected person will, on average, spread the coronavirus to one other person. If it’s 2, then an infected person will spread it to two on average. And so on.

It’s an attempt, then, to gauge how quickly a virus is spreading. One way to think about it: Unlike the count for daily new cases, this gives you a snapshot not of a state’s Covid-19 outbreak today, but of where the outbreak is heading in the near future.

The goal is to get the Rt below 1. If each infection doesn’t lead to another, that would over time lead to zero new Covid-19 cases.

The estimated Rt can be very imprecise, with margins of error that make it hard to know for certain in any state if it’s really above or below 1. Different modelers can also come up with different estimates. That’s, unfortunately, just the reality of using limited data to come up with a rough estimate of a disease’s overall spread.

The Rt also reflects an average. If 10 people are infected with Covid-19, nine spread it to no one else, and one spreads it to 10, that adds up to an Rt of 1. But it masks the fact that individuals, for whatever reason, can still cause superspreading events — which seem of particular concern with the coronavirus.

And the Rt is only as good as the data that goes into calculating it. If a state’s data is poor quality or inconsistent, it might skew the picture. That can help explain why some states with bad and continuing outbreaks may fare better on this benchmark than others.

Still, the Rt is one of the better measures we have for tracking a pathogen’s spread across the whole population. When paired with the other metrics on this list, it can give us a sense of each state’s outbreak now and in the future.

3) Most states’ positive rates for tests are too high

A map of Covid-19 positive rates in each state.

What’s the goal? Less than 5 percent of coronavirus tests coming back positive over the previous week, based on data from the Johns Hopkins Coronavirus Resource Center and the Covid Tracking Project.

Which states meet the goal? Alaska, California, Colorado, Connecticut, Hawaii, Illinois, Indiana, Maine, Maryland, Massachusetts, Michigan, Minnesota, Montana, Nebraska, Nevada, New Mexico, New York, North Dakota, Oregon, Rhode Island, Vermont, Washington, West Virginia, and Wisconsin — 24 states, as well as Washington, DC.

Why is this important? To properly track and contain coronavirus outbreaks, states need to have enough testing. There are all sorts of proposals for how much testing is needed in the US, up to the tens of millions.

But one way to see if a state is testing enough to match its outbreak is the rate of tests that come back positive. An area with adequate testing should be testing lots and lots of people, many of whom don’t have the disease or don’t show severe symptoms. High positive rates indicate that only people with obvious symptoms are getting tested, so there’s not quite enough testing to match the scope of an outbreak.

The goal for the positive rate is, in an ideal world, zero percent, since that would suggest that Covid-19 is vanquished entirely. More realistically, in a world going through a pandemic, the positive rate should be below 5 percent. But even if a state reaches 5 percent, experts argue it should continue trying to push that number further down — to match nations like Australia, New Zealand, and South Korea, which have gotten their positive rates below 3 percent or even 1 percent — in order to truly get ahold of their outbreaks.

As long as a state is above 5 percent, chances are it’s still missing a significant number of Covid-19 cases. And the higher that number is, the more cases that are very likely getting missed.

So even if your state is reporting a low number of daily new cases, a high positive rate should be a cause for alarm — a sign that there’s an outbreak that’s only hidden due to a lack of testing. And if your state is reporting a high number of daily new cases and a high positive rate, that’s all the more reason for concern, suggesting the epidemic is even worse than the total case count indicates.

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