Genetic Mystery: Why Some People Never Contract COVID-19

Since the pandemic's earliest days, medicine has grappled with one of its most humbling riddles: why some people, exposed intimately and repeatedly to COVID-19, never fall ill at all. Researchers across São Paulo, New York, and beyond are tracing the answer into the genome itself, finding clues in natural killer cells, interferon pathways, and the quiet architecture of inherited immunity. What emerges is not a clean explanation but a deeper appreciation for the complexity of human biology — a reminder that vulnerability and resilience are written in languages we are only beginning to read.