Live attenuated polio vaccine and the risk of intussusception

Aims Since suspicion has been raised that administration of an oral live attenuated rotavirus vaccine may increase the risk of intussusception in young children, there has been concern about the possible effects of oral polio vaccine. The aim of the study was to evaluate the relationship between oral attenuated polio vaccine and intussusception in children below the age of 1 year. Methods We conducted a nested case-control analysis based on data from the General Practice Research Database which encompassed 133 children who developed documented intussusception during the first year of life and 515 controls. Results The time from oral polio vaccine to the index date was similar in cases and controls. Relative risk estimates for intussusception ranged from 0.7 (95% CI 0.2, 2.1) for babies whose last oral polio vaccine was given 29-35 days before their index date to 1.0 (95% CI 0.4, 2.3) for those whose last oral polio vaccine was given 15-21 days before their index date (compared with babies vaccinated more than 43 days before their index date). Conclusions There is no suggestion that oral polio vaccine increases the risk for intussusception.