CD40LG and cytomegalovirus infection: In the U.S., CMV IgM seroprevalence in the general population have been briefly described among women aged 12–49 years from the National Health and Nutrition Examination Survey (NHANES) III 1988–1994.[7] The lack of temporal changes in CMV IgG seroprevalence from 1988–1994 to 1999–2004 [8] suggests that the factors associated with CMV transmission have remained fairly consistent over time and that findings on IgM seroprevalence from NHANES III are still informative for understanding the epidemiology of acute CMV infection and risk of transmission.