CXCL9 and viral infectious disease: There have been reports summarizing that most chemokines, such as CXCL2, CXCL9, and CXCL10, possess the ability to regulate the activation and migration of white blood cells, and control viral infections and the host defense functions of viral infections [33,34], but there is not yet a review summarizing the function of CX3CL1 in different viral infections.