In addition, interpretation of the results of currently available serologic methods for the diagnosis of acute infections in pregnant women is complicated by (i) the prevalence of T. gondii IgG antibodies in chronically infected women, (ii) the fact that T. gondii IgM antibodies may persist for a year or more after infection, and (iii) the fact that false-positive T. gondii IgM antibody results are not uncommon outside of reference laboratories (5, 6). The gene discussed is CD40LG; the disease is infection.