Since April a mysterious outbreak of hepatitis in children around the world has baffled doctors. Some children have required liver transplants and more than 20 have died. Recent findings may link the spike in cases to covid-19 lockdowns. We examine the evidence and ask how a lack of exposure to bugs can affect immune systems. What other consequences could pandemic restrictions have for the long-term health of children—and adults? Kenneth Cukier hosts. For full access to The Economist’s print, digital and audio editions subscribe at economist.com/podcastoffer and sign up for our weekly science newsletter at economist.com/simplyscience. Our GDPR privacy policy was updated on August 8, 2022. Visit acast.com/privacy for more information.