Is There a Link Between Administration of RotaTeq and Intussusception?
Haber P, Patel M, Izurieta HS, et al
Pediatrics. 2008; 121:1206-1212

This study by Haber and colleagues looked at rates of intussusception in children following vaccination with the bovine protein-containing rotavirus vaccine, RotaTeq™, which received licensure in February, 2006.

Infants in the United States currently receive 3 doses of this oral vaccine, given at 2, 4, and 6 months. The authors used several methods to assess whether RotaTeq™ was associated with increased risk of intussusception, including looking at data from 6 sites participating in the Vaccine Safety Datalink (a national HMO database sponsored in part by the CDC) and reports to the CDC's Vaccine Adverse Events Reporting System (VAERS).

The authors calculated "observed" vs "expected" rates of intussusception, and evaluated whether the rates of intussusception were higher than expected in the 2 data sets. The expected rates of intussusception were based on 2000-2004 rates, when no rotavirus vaccine was used in the United States.

During the 19-month study period, there were 160 cases of intussusception reported to VAERS. Approximately 15% of the cases occurred in the first week after vaccination. Based on background rates, the authors calculated that 50 cases of intussusception should have been reported to VAERS in the first week after vaccination. However, only 27 cases were reported as occurring within that window. Even with partial reporting estimates, the rate of observed intussusception (reported to VAERS) was below that expected. In the Vaccine Safety Datalink cohort, there were 3 cases of intussusception among > 100,000 children who were vaccinated vs 9 in > 160,000 children who did not receive RotaTeq™ children.

The authors conclude that the current evidence does not suggest a link between RotaTeq™ and intussusception.

Most pediatric practitioners are likely eagerly awaiting these results to reassure themselves and or their patients. As the authors note in their discussion, much of their findings depend on assumptions or calculations -- estimating the number of RotaTeq™ doses given based on number shipped, estimating the "background" rate of intussusception, etc. However, they also point out that these are perhaps the best data currently available. I suspect we will see additional estimates comparing actual reported rates to expected rates of intussusception as time goes by, but these data provide some reassurance for now.

Abstract