Nationwide population-based study showed that the rotavirus vaccination had no impact on the incidence of biliary atresia in Korea

Aim Rotaviruses have been associated with biliary atresia. This study investigated whether the rotavirus vaccine, which was introduced to Korea in 2008, had an impact on the incidence of biliary atresia. Methods We identified all rotavirus infections (n = 436 826) and biliary atresia cases (n = 528) diagnosed from 2006 to 2015 from insurance and health databases. The annual and seasonal incidence of biliary atresia and rotavirus infection rates in neonates and children were calculated. The difference in the risk of biliary atresia between rotavirus-infected and non-infected neonates was analysed. Results The incidence of rotavirus infections was 20.6 versus 13.4 per 1000 cases before (2006-2008) and after (2009-2015) vaccine implementation. However, neonatal rotavirus infection rates did not decrease, with an incidence of 14.5 versus 14.8 per 1000 cases before and after vaccination. The biliary atresia incidence remained constant at 12.0 per 100 000 cases. Rotavirus infections in neonates were a risk factor for biliary atresia (odds ratio 3.14, 95% confidence interval 1.87-5.26). Conclusion Rotavirus vaccination had no impact on the incidence of biliary atresia, possibly because the vaccination did not change the neonatal rotavirus infection rate through herd immunity. However, rotavirus infections in neonates were significantly associated with biliary atresia.