Researchers have developed a new approach to detecting a person’s immunity to an infectious disease — providing valuable details about whether and when a person was exposed to the infection. The test was developed for detecting recent exposure to malaria, but the research team are now working to adapt it to detect previous exposure to the coronavirus that causes COVID-19. By providing a detailed picture of when an infection spread in a community, the test offers new opportunities for improving infection control and elimination strategies — particularly in lower income countries.