Data Snapshot: The 2022 Mpox outbreak in review. Top ten nations by cases and deaths per capita.

In the spring and summer of 2022, Mpox (formerly known as monkeypox) was spreading rapidly around the world. But unlike Covid-19, this virus proved far easier to stop with a combination of behavioral changes and vaccines. While cases are still being reported, they are now rare.

Which nations had the most cases and deaths per capita? Take a look below. However, keep in mind that differences in cases per capita are as likely to reflect differences in testing capacity (or strategies) as anything about the populations themselves. Meanwhile, deaths per capita likely reflect who got infected. For example, I’d surmise that in Peru (where cases per capita were high, but deaths per capita were exceedingly high), a highly vulnerable group of people got infected. It wouldn’t take much for that to be the case because literally 15 people in Peru died of Mpox during the outbreak (which translates out to 4.5 per 10m people, as seen in the graph below).

In addition, we’ve learned more about the epidemiology of the Mpox outbreak in the US. In the end, most cases were among males (>95%). There were disparities along racial and ethnic lines.

Also, as I first wrote in Inside Medicine last summer, pre-symptomatic spread is now understood to occur and acknowledged by experts. Also, as I wrote here, casual/passive contact did not seem to be “enough” to spread this virus (if it had been routinely spreading that way, the gender breakdown would not have mainly remained among males).

Lastly, you may have noticed that the fatality rate in this Mpox outbreak was much lower than in during prior outbreaks. In fact, in the past the case fatality rate of Mpox was 3-11%. In this outbreak, it was closer to 0.1% (96 deaths worldwide out of 85,922 cases, or around 1 for every 895 documented cases). That’s likely mostly due to the same factors driving the differences seen in the two graphs above (increased testing capacity/liberal testing strategies in some places and the risks of the affected populations) plus, to some extent, the success of vaccination campaigns.

All told, this outbreak was bad, but could have been a whole lot worse.

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