Relationship between Pentavalent Rotavirus Vaccine and Intussusception: A Retrospective Study at a Single Center in Korea

Abstract

Purpose: Despite withdrawal of RotaShield® and the development of second generation live attenuated rotavirus vaccines, concerns remain regarding the relationship between rotavirus vaccine and intussusception. Nevertheless, since there is no study in Korea, we reviewed data from cases at Severance Children's Hospital to determine the association between rotavirus vaccine and intussusception.

Materials and methods: Patients coded as intussusception and following a prescription of RotaTeq® from 2007 to 2013 were reviewed. We calculated comparative incidence figures (CIFs) and 95% confidence intervals (CIs) to compare the risk of intussusception in Korea with the risk in the United States. Expected cases within the four-week post-vaccination window were calculated by applying rates of intussusception from data compiled by the Health Insurance Review and Assessment Service (for a five-year period) to numbers of vaccinations.

Results: In total, 10530 doses of pentavalent rotavirus vaccine were administered. A total of 65 intussusception cases were diagnosed, although only two cases occurred within four weeks after vaccination. This was compared to six cases within 999123 doses in United States from April 2008 to March 2013 (CIF, 31.63; CI, 31.33-31.93). When we adjusted incidence rate differences for both countries, the CIF decreased to 7.05 (CI, 6.72-7.40). When we compared our identified cases with the expected cases from our hospital, there was no increased intussusception occurring within four weeks of vaccination.

Conclusion: We found no association between pentavalent rotavirus vaccine and intussusception. Therefore, rotavirus vaccination should be considered due to its benefits of preventing rotavirus-associated diseases.

Keywords: Korea; Pentavalent rotavirus vaccine; intussusception.

Fig. 1. Plot showing a trend for the total infants below 12 months of age who visited our hospital (black line), and total diagnosed and treated intussusception infants below 12 months of age in our hospital (gray line) between 2005 and 2013. The tendency of intussusception decreased across most of the years studied. The reason for the increased number of intussusceptions in 2012 remains unclear.

Fig. 2. Number of incidents over the observation period divided into two-month intervals. A periodic increase in incidents is seen; however, the overall pattern is a decline in incidence. The incidence rate was calculated using standard poisson-based methods, and a decrease in the risk ratio by 0.51 was observed.