How Could Rotashield® Cause Intussusception?
The “unique strain” hypothesis posits that the G3 strain, that was a simian rotavirus strain RRV and not a human-rhesus re-assortment strain, could invade the small intestines, possibly leading to intussusception. The “heterologous host strain” hypothesis is that because cross-species infections are rare, immunization with Rotashield may differ in certain ways with natural infection, and the biological features of the heterologous strains may lead to intussusception. The “bolus dose” hypothesis states that the critical difference between Rotashield immunization and natural infection is the dose of virus. In natural infections, relatively small numbers of virus are ingested, and they infect the proximal small intestine first. Immunization, on the other hand, administers a large number of viruses, and they may replicate in sites different from those of natural infection.
