abstract
Several case reports have described immune hemolytic anemia (IHA) following vaccination in children. We examined the risk of IHA in the 42 days following vaccination exposure using a self-controlled case series study design. In our population-based cohort of nearly 4.5 million children in the Vaccine Safety Datalink, we identified 55 confirmed cases of new-onset IHA from 1991 through 2000. We found no association between IHA and diphtheria-pertussis-tetanus vaccination (incidence rate ratio (IRR)=0.65, 95% CI: 0.19-2.24), hepatitis B vaccination (IRR=1.73, 95% CI: 0.59-5.01), or any vaccination (IRR=1.04, 95% CI: 0.46-2.32).
