CD40LG and anemia (phenotype): A study in Italy reported that parvovirus B19 can persist in immunocompetent symptomatic and non-symptomatic individuals by the presence of viral DNA in different tissue but this was observed in the absence of viraemia and anti-B19 IgM.13 These results have implications for children under the age of five years, because such children are vulnerable to the detrimental effects of anaemia.