BACKGROUNDER | A veterinary tranquilizer is compounding a crisis of drug deaths
Tech titans call for a pause in developing more powerful artificial intelligence tools
Emma Freire | On the third anniversary of lockdowns, experts reassess the sharp divide over COVID vaccines
BACKSTORY | The challenges of reporting on America’s vaccine controversy
TECHNOLOGY | Field-testing DuckDuckGo’s AI-powered search engine
BY THE NUMBERS | Lower prices will give financial relief to Americans living with diabetes
SCIENCE | Scientists hope a blood test can improve treatment
