In humans, autosomal recessive deletion of UNC93B1 gene was found in children suffering from sporadic herpes simplex virus 1-associated encephalitis and autosomal dominant deficiency was recently detected in SARS-CoV-2-infected patients suffering from life-threatening pneumonia, demonstrating the physiological importance of UNC93B1-TLR interaction in host defense (14–16). The gene discussed is UNC93B1; the disease is encephalitis.