A large South African household study has quietly unsettled one of medicine's foundational assumptions about influenza: that antibodies, once present at sufficient levels, reliably confer protection. Tracking over 1,500 people across three flu seasons, researchers found that children under five remained dramatically more vulnerable to infection and contagious far longer than adults — not because they lacked antibodies, but because something deeper in the biology of early childhood resists the protection those antibodies are supposed to provide. The finding asks us to reckon with how much of wh
Children's Influenza Vulnerability Persists Despite Protective Antibodies
Children under 5 face significantly elevated infection risk and prolonged illness duration compared to older populations, affecting household transmission and disease burden.