As the serum/plasma samples were diluted 1/10 in these assays, these findings suggest that more than 13.6% of patients with life-threatening COVID-19 have circulating auto-Abs neutralizing 1 ng/mL IFN-α2 and/or IFN-ω in vivo, a greater proportion than the 10% of patients with auto-Abs neutralizing 100 ng/mL reported in previous studies (9, 11–15, 35). Here, IFNA2 is linked to COVID-19.