A High Incidence of Intussusception Revealed by a Retrospective Hospital-Based Study in Nha Trang, Vietnam between 2009 and 2011

Rotavirus is a leading cause of severe diarrhea among children worldwide. Thus, the World Health Organization recommended including rotavirus vaccines in national immunization programs. One concern about rotavirus vaccine, however, is a possible association with intussusception. Thus, it is crucial to know the baseline incidence of intussusception in the first year of life. A study conducted in Hanoi, Vietnam showed that the incidence of intussusception was the highest in the world. This retrospective cross-sectional study was undertaken to determine the incidence of intussusception among children <5 years of age in Nha Trang, Vietnam. Hospital charts between 2009 and 2011 were reviewed in Khanh Hoa Provincial General Hospital where virtually all cases of intussusception occurring in the city were assumed to have been encountered. The incidence of intussusception among children <1 year of age was 296 per 100,000 person-years (95% confidence interval [CI]: 225-382), and that among children <5 years of age was 196 per 100,000 person-years (95% CI: 169-226), confirming the high incidence of intussusception in Vietnam. Nevertheless, there was no intussusception in the first three months of life. We therefore recommend that the first dose of any rotavirus vaccine be administered to infants between 6 and 12 weeks of age.