We describe a case of vaccine-associated measles in a two-year-old patient… who received her first dose of measles-containing vaccine 37 days prior to onset of prodromal symptoms.
In this report we describe a case of measles-mumps-rubella (MMR) vaccine-associated measles illness that was positive… five weeks after administration of the MMR vaccine.
[A] two-year-old child living in the Fraser Valley presented to the family physician with fever, rash, conjunctivitis and coryza. Symptoms had begun two days before, with a runny nose, followed by fever on the day hereafter. A macular rash appeared on the day of visiting the physician, starting on the face and progressing to the rest of the body…
Virus genotype was determined by the National Microbiology Laboratory… as vaccine strain…
Based on our review of the literature, this report documents the first case of MMR vaccine-associated measles, 37 days post-immunisation, well beyond 21 days and the routine 30 days post-MMR immunisation period used by the Canadian adverse event following immunization (AEFI) surveillance system.
Clinically significant vaccine-associated illness is rare, but when it occurs it is indistinguishable from wild-type measles, except by genotyping.
Detection of vaccine virus has been documented up to 14 days post-immunisation by RT-PCR, and up to 16 days by immunofluorescence microscopy of urine sediment. Complications from vaccine-associated measles have been documented in both immune-competent and compromised individuals.
Heightened surveillance and awareness of measles because of the ongoing outbreak likely contributed to the identification of this case.
[I]t likely represents the existence of additional, but unidentified, exceptions to the typical timeframe for measles vaccine virus shedding and illness.
Further investigation is needed on the upper limit of measles vaccine virus shedding…