CXCL2, CXCL12, CXCL13, CCL1, CCL7, CCL8, CCL13, CCL18, CCL19, CCL22, CCL24, and CX3CL1 were detected in the peripheral blood of both the RSV bronchiolitis group and the control group. The gene discussed is CCL7; the disease is respiratory syncytial virus bronchiolitis.