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Back in the spring, before the first surge of the coronavirus had fully diminished, public-health experts were already warning of a second surge. Shutdowns were ending and public spaces reopening, but as the months turned cold, they said, cases could spike again—more dramatically, even, than in the first wave.

The reprieve after the first wave, though, was short: By June, case numbers were climbing again. As northerners were headed outside, southerners were headed inside, where the virus spreads most easily, and the country’s summer surge began.

By this way of looking at the pandemic—the increases, dips, and plateaus in case numbers on a national scale—the United States is in its third surge. Cases, hospitalizations, and deaths all peaked and then subsided first in April and again in August. When the current surge will peak is not yet clear.

Read: One day, 3,000 deaths

Another way of looking at it takes into account the pandemic’s patchwork spread. At the state level, only one state, Louisiana, has suffered three major surges. In some of the places hit worst in the earlier surges, November and December mark the virus’s first resurgence. In New Jersey and Connecticut, hospitalizations are climbing again to levels not seen since spring, and in Arizona and Texas, they are as high as they ever were.

This chart shows the states where hospitalizations hit at least 300 people per million in at least two nonconsecutive weeks, according to data from the COVID Tracking Project at The Atlantic. This level of hospitalization is a good measure of the pandemic’s local severity, both because it captures serious cases that aren’t limited to deaths and because hospitalization data are reliable over short time frames (unlike data for cases and deaths, which can be delayed by weekends and holidays). This cutoff, 300 per million, is somewhat arbitrary, but it captures the states that have generally suffered the most during the pandemic.

Using this measure, the beginning of the pandemic, when the dimly understood novel coronavirus spread rapidly through the East Coast, shows up clearly. Illinois, Michigan, and Louisiana all had major outbreaks as well, generally centered on the metropolitan areas of Chicago, Detroit, and New Orleans.

At the end of March, The New York Times reported that Louisiana had perhaps the fastest growth in cases in the world—2,305 cumulative cases through March 26—perhaps because of Mardi Gras. In Michigan, officials and experts pointed to deep poverty and lack of resources in the Detroit metro area to explain the disproportionate impact there: thousands of homes without water, high levels of multigenerational housing, few jobs in which residents can work remotely. Chicago faced similar problems. The initial surge swept first through the city’s Black communities; of the first 1,000 COVID-19 deaths in Cook County, half of the victims were Black, twice their proportion of the population. Again, local experts attributed the numbers to a combination of inequalities, including poverty, underlying health conditions, and struggling hospitals; the county’s massive jail was also the country’s worst COVID-19 hot spot in early April.

Read: The pandemic’s final surge will be brutal

As the problem in those states began to subside, hospitalizations were on the rise in the Sun Belt, from the South through the Southwest. Why was the problem worse in the Sun Belt during the summer? A few theories have been suggested. First, the rise coincided with business reopenings across the region. Places hit harder early on were slower to reopen; across the Sun Belt, by contrast, states went through what Alexis Madrigal and Robinson Meyer call “all or nothing” reopenings. Second, the Northeast and the Midwest are often unpleasant outside in the early spring and lovely during the summer, while the reverse is often true in the Sun Belt. In that last week of June, “America lost control of the pandemic,” as Meyer wrote at the time, and 16 states hit their highest case counts, most of them Sun Belt states.

Now the situation is much worse than that awful week. Of the 12 states that have exceeded 300 hospitalizations per million twice during the pandemic, all 12 were above that threshold during the week of December 6. Louisiana is above that threshold for the third time this year—it suffered through the first round of uncontrolled community spread, then through the Sun Belt surge, and again through the winter surge. Half of those 12 states have higher hospitalization rates now than during their first surges.

In the first few months of the pandemic, the virus came in waves, rising in one place, falling in another. Now it’s rising almost everywhere. With federal assistance drying up, improvement in the unemployment rate slowing, and consumer spending down, states and municipalities have been slow to go through another round of shutdowns. Nowhere in the country has the virus ever been truly driven back; when the conditions were right, it surged again.