In many infections, the immune system builds so-called germinal centers (yellow-brown rings inside the blue) in the spleen or lymph nodes to train cells that make antibodies, but the structures fail to develop in some COVID-19 cases.
By Jon CohenScience’s COVID-19 reporting is supported by the Pulitzer Center and the Heising-Simons Foundation.At the top of the long list of uncertainties about COVID-19 is whether people who recover will develop durable immune responses to the coronavirus that causes it.