Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain
the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in
Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles
and JavaScript.
Meta’s planned shift away from third party fact-checking in favour of a crowdsourced approach has perplexed those who study the spread of misinformation.
The threshold has been exceeded for only one year so far, but humanity is nearing the end of what many thought was a ‘safe zone’ as climate change worsens.
Pharmaceuticals and vector-control programmes have greatly diminished the once-widespread disease, but sustained effort will be needed to stamp out infection for good.