Long-term trends in pediatric intussusception in Hokkaido, Japan, 2007-2024 across the rotavirus vaccination era.

Abstract

Objectives: Pediatric intussusception is the most common cause of acute intestinal obstruction in young children. We investigated long-term epidemiological trends in pediatric intussusception before and after rotavirus vaccine introduction and during the COVID-19 pandemic in Hokkaido, Japan.

Methods: A retrospective multicenter surveillance study was conducted at 17 hospitals in Hokkaido between 2007 and 2024. Clinical characteristics, management, outcomes, and viral antigen test results were collected. Only cases fulfilling Brighton Level 1 diagnostic certainty were included. Annual incidence rates were calculated using regional population statistics.

Results: A total of 513 children met the inclusion criteria, with 93.0% aged 0-4 years. Non-surgical reduction was successful in 94.0% of cases, and no deaths or long-term sequelae were observed. Among infants aged <1 year, incidence decreased from 99.4 per 100,000 person-years during the pre-vaccination period (2007-2011) to 69.9 during the voluntary vaccination period (2012-2019), and was 79.7 during the universal vaccination/COVID-19 period (2020-2024). Corresponding incidence rates among children aged 0-4 years were 55.4, 36.7, and 38.1 per 100,000 person-years, respectively.

Conclusion: Among children aged 0-4 years, intussusception incidence was lower during the period following rotavirus vaccine introduction than during the pre-vaccine period and remained broadly stable during the universal vaccination and COVID-19 period. The observed changes cannot be attributed to rotavirus vaccination alone because of concurrent changes in infectious disease circulation and other population-level factors. Continued surveillance is warranted to further clarify the epidemiology of pediatric intussusception.