GM-CSF might be a key mediator of SARS-CoV-2-induced cytokine storm in a subset of COVID-19 patients with severe outcomes (Hamilton, 2020; Hue et al. 2020; Gibellini et al. 2020; Blot et al. 2020; Thwaites et al. 2021; Zhao et al. 2021). Here, CSF2 is linked to COVID-19.