Medical Express Five years ago, at the outset of the coronavirus pandemic, a phenomenon became abundantly clear: Preschool-age children rarely developed severe cases of COVID-19. It wasn’t that children under the age of 5 were avoiding infection. To the contrary, they were coming down with COVID like everyone else. In the United States, the Centers for Disease Control and Prevention estimates that more than 90% of children from infancy through age 17 have been exposed to SARS-CoV-2, the virus that causes COVID.
What made the youngest population of children different is their generally striking avoidance of severe coronavirus infection. That fact has led scientists worldwide to seek an answer to a deceptively simple question: How does the youngest population of children, no matter where they are in the world, continually elude severe COVID?