In the current study, we observed that under the challenge of VSV and LPS, the expression of hepatic rate-limiting enzymes Cyp7a1, Cyp27a1, Cyp8b1, and Hsd3b7, as well as circulating CA and CDCA were all significantly decreased in mice, suggesting that infections may interfere with the synthesis process of BAs in the liver. This evidence concerns the gene CYP7A1 and infection.