BDV induced local C1q mRNA expression in the hippocampus and cortex (Dietzschold et al., 1995) and ZIKV infection enhanced expression of C1q and C3, associated with microglial activation and hippocampal synaptic damage and memory impairment in a murine infection model using ZIKV intracerebroventricular infusion (Figueiredo et al., 2019). This evidence concerns the gene C3 and infection.