Can Flanders resist the measles outbreak? Assessing vaccination coverage in different age groups among Flemish residents.

The Belgian strategic plan to eliminate measles contains several vaccination strategies including routine immunisation programmes and catch-up campaigns. A new expanded programme on immunisation-based survey (2016) assessed the uptake of the recommended measles-mumps-rubella (MMR) vaccine in three different cohorts: toddlers, adolescents and parents of toddlers. A two-stage cluster sampling technique was used to select 875 toddlers (age 18-24 months) and 1250 adolescents (born in 2000) from 107 municipalities in Flanders. After consent of the parent(s), 746 (85.2%) families of toddlers and 1012 (81.0%) families of adolescents were interviewed at home. Measles vaccination coverage was high at 18-24 months (96.2%) and 81.5% were vaccinated at recommended age. Toddlers who had two siblings or a non-working mother or changed vaccinator were more at risk for not being vaccinated. Coverage of the teenager dose reached 93.5% and was lower in adolescents with educational underachievement or whose mother was part-time working or with a non-Belgian background. Only 56.0% of mothers and 48.3% of fathers remembered having received at least one measles-containing vaccine. Although measles vaccination coverage in toddlers meets the required standards for elimination, administration of the teenager dose of MMR vaccine and parent compliance to the recent measles catch-up campaign in Flanders leave room for improvement.