HMOX1 and viral infectious disease: Since the discovery of HO-1 in 1968 [13] as the crucial enzyme in scavenging the hemoglobin and heme toxicity effects by catalyzing pro-inflammatory hemoglobin and heme to their anti-inflammatory catabolic products bilirubin and CO [14], a substantial progress has been made to explore its potential against numerous pathological conditions, including viral infections.