These findings are relevant to COVID-19 because all of these disorders induce inflammation1,8,9 and yet still benefit from treatment with GM-CSF, whichincreases, rather than decreases, the number and activation of microglia, the resident phagocytes of the CNS that are often cited as indicators of a dangerous pro-inflammatory milieu that must be suppressed to achieve successful treatment. This evidence concerns the gene CSF2 and COVID-19.