title: Long-lasting measles outbreak affecting several unrelated networks of unvaccinated persons.
abstract: Despite a population immunity level estimated at approximately 95%, an outbreak of measles responsible for 94 cases occurred in Quebec, Canada. Unlike previous outbreaks in which most unvaccinated children belonged to a single community, this outbreak had cases coming from several unrelated networks of unvaccinated persons dispersed in the population. No epidemiological link was found for about one-third of laboratory-confirmed cases. This outbreak demonstrated that minimal changes in the level of aggregation of unvaccinated individuals can lead to sustained transmission in highly vaccinated populations. Mathematical work is needed regarding the level of aggregation of unvaccinated individuals that would jeopardize elimination.
authors.affiliation: Department of Preventive and Social Medicine, Faculty of Medicine, Laval University, Quebec, PQ, Canada.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Dallaire
authors.forename: Gaston
authors.initials: G
authors.lastname: De Serres
authors.forename: François-William
authors.initials: FW
authors.lastname: Tremblay
authors.forename: France
authors.initials: F
authors.lastname: Markowski
authors.forename: Graham
authors.initials: G
authors.lastname: Tipples
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D016358:Contact Tracing; D004196:Disease Outbreaks; D005260:Female; D006801:Humans; D032521:Immunity, Herd; D008297:Male; D008457:Measles / Q000453:epidemiology* / Q000235:genetics; D008458:Measles Vaccine / Q000627:therapeutic use; D008969:Molecular Sequence Data; D011792:Quebec / Q000453:epidemiology; D016312:Treatment Refusal; D055815:Young Adult
chemical_list: D008458:Measles Vaccine