The lungs were bogged with fluid; debris from dead cells clogged the air sacs. “There appears to be a fork in the road to immunity to Covid-19 that determines disease outcome,” Iwasaki told me. “If you mount a robust innate immune response during the early phase of infection [presumably via an intact type 1 interferon response], you control the virus and have a mild disease. If you don’t, you have uncontrolled virus replication in the lung that […] fuels the fire of inflammation leading to severe disease.”
