Miyazono Y, Arai J, Kanai Y, et al. - Through conducting a nationwide prospective survey in Japan, researchers sought to examine the clinical background, course, prognosis, and incidence of the relatively novel late‐onset acute hemolytic disease in very low birthweight (VLBW) infants. From 2011 to 2015, a nationwide prospective survey was performed as a rare disease surveillance project of the Japan Society for Neonatal Health and Development. There were 24 confirmed cases. No recurrence of the hemolytic episode occurred during the observation period. In this study, 9 to 33 days after birth in Japan, at least 1 out of 1,259 VLBW infants experienced hemolysis. This disease should be recognized as among the significant pathological conditions of VLBW infants due to the risk of kernicterus, indicating the need to manage jaundice and anemia up to 5 weeks after birth.