Open AccessPublished:September 23, 2021DOI: https://doi.org/10.1016/j.ijid.2021.09.043 Objectives Hyper-inflammation caused by COVID-19 may be mediated by mast cell activation (MCA) which has also been hypothesized to cause Long-COVID (LC) symptoms. We determined prevalence/severity of MCA symptoms in LC. Methods Adults in LC-focused Facebook support groups were recruited for online assessment of […]