Longitudinal trends of neutralizing antibody prevalence against human cytomegalovirus (HCMV) over the past 30 years in Japanese women

Abstract

The neutralizing antibodies (NAb) to HCMV in women are associated with the risk of transplacental infection of the fetus with HCMV in pregnant women. The IgG-positive rate determined with enzyme immunoassay (EIA) or indirect immunofluorescence assay has decreased approximately from 100% to 70% over the past 30 years in Japan. We tested serum samples from 630 women in Japan aged 20 to 49 years from whom blood had been drawn between 1980 and 2015. We measured the IgG titer using an EIA-based assay and the HCMV-NAb titer with neutralization test assay using an HCMV isolate on human retinal epithelial cells. Longitudinal transitions of HCMV-NAb prevalence were clarified. The prevalence of HCMV-EIA-IgG, HCMV-NAb of 16 titer, and HCMV-NAb of 100 titer changed from 96.6 to 78.9%, 93.3% to 85.6%, and 35.5% to 41.1%, respectively, between 1980-1990 and 2010-2015. HCMV NAb prevalence at the titer of 16 decreased by 7.7%, whereas that at the NAb titer of 100 increased by 4.6%. It is expected that HCMV NAb with high titer in pregnant women reduces the risk of intrauterine HCMV transmission from mother to fetus. The association between the risk of congenital HCMV infection and HCMV-NAb prevalence remains to be addressed.