TLR7 and COVID-19: However, given that (i) TLR7 signaling promotes both inflammatory and antiviral responses, (ii) human studies provide correlative evidence for the role of TLR7 activity in severe COVID-19, and (iii) there is an incomplete understanding of the in vivo role of TLR7 signaling in lung antiviral and inflammatory responses, the conclusive evidence demonstrating the role of TLR7 signaling in lung viral replication, lung antiviral and inflammatory responses, pulmonary damage, and disease outcomes is lacking.