On New Year's Eve 2019, China notified the World Health Organization of a cluster of cases of "pneumonia of an unknown cause."

The big picture: The year since then has been defined all over the world by the struggle against a virus that has now claimed at least 1.6 million lives. But its toll has been unevenly distributed.

By the numbers: Residents of the European Union have died at 16 times the rate of Africans and 30 times the rate in Oceania, according to the official data (levels of testing and transparency vary).

• While one in every 1,000 Peruvians has died of the virus, just one in every 3 million Taiwanese has.
• Americans have died at 2.5 times the rate of Canadians and 46 times the rate in Japan.

Breaking it down: Western Europe has seen two massive waves — one peaking in April, the other in November. Countries including Belgium, Italy, Spain and France (12th on this list) were hit particularly hard by both waves.

Central and Eastern Europe largely avoided the worst of the first wave, but now countries there are facing the most dire crises anywhere in the world.

• Slovenia (pop. 2 million), for example, had recorded just 150 total deaths as of Oct. 1. Over the next 10 weeks, that number jumped to over 2,000.
• If the U.S. was experiencing Slovenia's current death rate, it would be recording 50,000 deaths per week.

In Latin American countries like Peru, Argentina, Mexico (13th) and Brazil (14th), death tolls began to climb more gradually in the spring, but have never really been brought under control since.

• That's also the case in the U.S., which crossed 300,000 deaths on Monday.

Breaking it down: The death rates in Mexico and France are virtually identical. But their trajectories — as seen through rolling 7-day averages of new deaths — tell very different stories.

• France was averaging 975 deaths per day at one point during the spring peak, and as few as 8 per day during the summer lull.
• Mexico hasn't hit such a sharp peak, but has been consistently averaging over 300 deaths per day since May.

Zoom in: Belgium has been hit hardest of all by coronavirus death rates.

Worth noting: Belgium's tally includes suspected COVID-19 deaths in facilities such as nursing homes, even without a positive test, which authorities have cited as one reason the country's death rate is so high.

• Other explanations include regional divisions, an overcomplicated bureaucracy and muddled public messages.

What to watch: Producing, distributing and administering vaccines globally will be the driving challenge of 2021, and likely beyond.

Note: Our graphic excludes countries with populations under 1 million.