CD40LG and chlamydia infectious disease: Among the 1,480 children, 1,253 (84.66%) had EBV infection (i.e., were EBV-DNA positive or IgM positive), 796 (53.78%) had CMV infection, 806 (54.46%) had M. pneumoniae infection, 159 (10.74%) had parvovirus infection, 38 (2.57%) had influenza virus infection, 25 (1.69%) had adenovirus infection, and 1 (0.07%) had chlamydia infection (Fig. 1).