U1 and COVID-19: In our study, the positivity rate of ANA in COVID-19 patients (6.4%) is not significantly different from that in the general Chinese population.One study analyzed 12 types of autoantibodies in 21 patients with severe and critical COVID-19 infections, reporting detection rates of 50% for ANA, 25% for anti-Ro-60 antibodies, 20% for anti-Ro-52 antibodies, 5% for anti-DNA topoisomerase I (Scl-70) antibodies, and 5% for anti-U1 ribonucleoprotein (U1-RNP) antibodies (4).