The world is losing the battle against the coronavirus. As of last week, COVID-19 caseloads were rising in 115 countries and falling in just 83. Of the countries with rising caseloads, 26 saw new cases double over the previous week.

But the structure of the pandemic shows striking local differences. While the United States is experiencing its third wave of the virus, some countries are just now having their first. Falling temperatures in the Northern Hemisphere, eased restrictions and an overwhelming sense of fatigue are transforming coronavirus superstars into basket cases.

The Czech Republic, for example, was reporting just three COVID-19 deaths per day in August. By November, the figure had soared to over 200 deaths per day. Poland had 475 new cases per day in mid-September. Two months later, it was averaging 25,000.

This pattern of low cases for months before an autumn explosion has played out in every part of the world. Jordans caseloads were in the single digits all year, then rose steadily to 54 per day by Sept. 1, then 900 per day by Oct. 1, then up to 3,500 per day by Nov. 1. Turkeys caseloads have skyrocketed to the point that the graph line is almost vertical, rising tenfold since mid-November.

Even in Asia, where strict lockdowns, widespread testing and diligent contact tracing have kept cases impressively low, Japan and South Korea are now both experiencing alarmingly high infection rates.

So what happened? How did so many countries that managed the first six months of the pandemic so well suddenly drop the ball?

The answer has to do with the changing structure of the pandemic and the shifting incentives for the politicians tasked with managing it. As the coronavirus pandemic approaches its first birthday, both factors will have profound implications for the struggle against the pandemic in the United States.

A Changing Pandemic

Grzegorz Rempala, a mathematical epidemiologist at the Ohio State University, has spent the last three months watching the same pattern play out in Ohio, where he lives, and in Poland, where he grew up. After a long stretch of low caseloads, COVID-19 exploded in both places in the late summer.

The explanation, he said, is the shifting structure of the pandemic. In the spring, infections were clustered among high-risk groups: health care staff, nursing home residents, prisoners and essential workers. The virus hopped from cluster to cluster but remained relatively concentrated in workplaces and urban areas.

Over the summer, however, the virus generalized. Essential workers brought the virus home to their families, travelers spread it around the country and churches and other large gatherings became superspreader events. The virus remained at low levels in the population, but it spread to younger populations and suburban and rural areas many of which hadnt experienced widespread infection earlier in the year.

For months, huge regions of Europe and the U.S. didnt see very many COVID deaths or cases, Rempala said. People knew they were supposed to be masking and social distancing, but many of them simply chose not to because they didnt know anyone who had tested positive.