This pattern is consistent with the overexpression of genes annotated to the type-1 interferon system in the hippocampi of 6- to 10-wk-old mice in response to viral infection (76), in the interleukin-17 process observed in the ventral hippocampus of adolescent mice exposed to polyI:C during gestation (77), and in the hippocampus of pigs exposed to gestational and juvenile inflammatory signals (7). This evidence concerns the gene IL17A and viral infectious disease.