IFNA2 and COVID-19: The risk of critical COVID-19 in adults with auto-Abs neutralizing IFN-α (regardless of their ability to neutralize IFN-ω) is much higher than that in adults with auto-Abs neutralizing IFN-ω only (P = 0.008 at 100 pg/ml and P = 0.0006 at 10 ng/ml; Table 5).