Diagnostic tests used for confirmation of B19 V include serum specific IgG antibodies testing which is used to confirm an exposure to B19 V infection, serum IgM antibodies testing which is recommended to diagnose acute viral infection and remain detectable several months after infection, and other diagnostic tests such as viral DNA detection by using the PCR technique [7, 11, 13]. The gene discussed is CD40LG; the disease is viral infectious disease.