Live vaccines following intravenous immunoglobulin for Kawasaki disease: Are we vaccinating appropriately?

Aim: Australian and New Zealand guidelines recommend that live vaccines be postponed for 11 months after treatment of Kawasaki disease (KD) with intravenous immunoglobulin (IVIG). We aimed to describe patterns of live-vaccine administration after KD treatment, focusing on the measles-mumps-rubella/measles-mumps-rubella-varicella (MMR/MMRV) vaccines, and to compare real-world practice with current recommendations.

Methods: We combined data from inpatient Electronic Health Records and the Australian Immunisation Register for all children who received IVIG for the treatment of KD under the age of 5 years at two Australian tertiary children's hospitals over a 12-year period. Children who received IVIG <11 months before a scheduled MMR/MMRV were deemed 'at risk' of breaching the guidelines, and those whose subsequent vaccination occurred <11 months after the IVIG were deemed to have 'breached' the guidelines.

Results: Of those at risk, three-quarters (76%) breached the guidelines for their first MMR/MMRV. Findings were similar (50%-80%) for the second MMR/MMRV dose.

Conclusions: The majority of Australian children treated for KD with IVIG may not be optimally protected by MMRV vaccination. Immunisation systems should address this avoidable risk.