(*4), pleural effusion and peritoneal effusion (*5) are among the characteristic symptoms of congenital CMV infection. Approximately 90% of infants who experience these clinical manifestations are left with the aforementioned severe aftereffects. In recent years, it has been discovered that treating newborns with these clinical manifestations of congenital CMV infection with the antiviral drug, Valganciclovir, can improve not only hearing issues but also reduce delays in mental and physical development. In Japan, a clinical trial is ongoing to approve the neonatal therapies as treatments cov...