Coulby Cameron, Domingo Francesca Reyes, Hiebert Joanne, MacDonald Diane
Centre for Immunization and Respiratory Infectious Diseases, Public Health Agency of Canada, Ottawa, ON.
National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, MB.
Can Commun Dis Rep. 2020 Apr 2;46(4):77-83. doi: 10.14745/ccdr.v46i04a04.
Measles has been eliminated in Canada since 1998. Every year, the Public Health Agency of Canada presents epidemiologic evidence to the Pan American Health Organization (PAHO) to verify that measles continues to be eliminated in Canada. The objectives of this article are to: provide an epidemiologic summary of measles activity reported in 2018 in Canada, and provide documented evidence to support the continued verification of measles elimination status in Canada.
Measles surveillance data were captured by the Canadian Measles and Rubella Surveillance System (CMRSS) and descriptive analyses of demographics and risk factors were performed. Outbreak characteristics were summarized and genotypic analyses conducted. Surveillance data for 2018 were evaluated against PAHO's essential criteria for measles elimination status.
In 2018, 29 measles cases were reported across five provinces in Canada, an incidence rate of 0.8 cases per 1,000,000 population. Of these 29 cases, 16 were imported and five resulted in further transmission within Canada. The age-specific incidence rate was highest among those aged younger than one year (10.2 cases per 1,000,000 population, n=4). Only nine cases were considered up-to-date for measles vaccination, and 11 cases were hospitalized. Genotype information was available for most of the measles cases (n=27); they were all found to be genotypes that circulated globally in 2018. Canada met or partially met three out of four of PAHO's criteria for verification of measles elimination.
Although importations and areas of low vaccination coverage continue to challenge Canada's elimination status, there is no evidence that endemic transmission of the measles virus has been re-established. Canada maintains its measles elimination status.
自1998年以来，加拿大已消除麻疹。每年，加拿大公共卫生署都会向泛美卫生组织（PAHO）提供流行病学证据，以证实加拿大持续维持麻疹消除状态。本文的目的是：提供2018年加拿大报告的麻疹活动的流行病学总结，并提供书面证据以支持对加拿大麻疹消除状态的持续核实。
通过加拿大麻疹和风疹监测系统（CMRSS）收集麻疹监测数据，并对人口统计学和风险因素进行描述性分析。总结疫情特征并进行基因分型分析。根据PAHO的麻疹消除状态基本标准对2018年的监测数据进行评估。
2018年，加拿大五个省份共报告了29例麻疹病例，发病率为每100万人口0.8例。在这29例病例中，16例为输入性病例，5例在加拿大境内导致了进一步传播。年龄别发病率在1岁以下人群中最高（每100万人口10.2例，n = 4）。只有9例被认为麻疹疫苗接种及时，11例住院治疗。大多数麻疹病例（n = 27）可获得基因型信息；所有病例均为2018年在全球传播的基因型。加拿大在PAHO的四项麻疹消除核实标准中，有三项达到或部分达到。
尽管输入病例和疫苗接种覆盖率较低的地区继续对加拿大的消除状态构成挑战，但没有证据表明麻疹病毒已重新建立地方性传播。加拿大维持其麻疹消除状态。
