Health Sciences unit, Faculty of Social Sciences, Tampere University, Tampere, Finland.
Infectious Disease Control and Vaccinations Unit, Department of Health Security, Finnish Institute for Health and Welfare, Helsinki, Finland.
PLoS One. 2021 Apr 23;16(4):e0250674. doi: 10.1371/journal.pone.0250674. eCollection 2021.
We describe the epidemiology of tuberculosis (TB) and characterized Mycobacterium tuberculosis (M. tuberculosis) isolates to evaluate transmission between foreign-born and Finnish-born populations. Data on TB cases were obtained from the National Infectious Disease Register and denominator data on legal residents and their country of birth from the Population Information System. M. tuberculosis isolates were genotyped by spoligotyping and Mycobacterial Interspersed Repetitive Unit Variable Number Tandem Repeat (MIRU-VNTR). We characterized clusters by age, sex, origin and region of living which included both foreign-born cases and those born in Finland. During 2014-2017, 1015 TB cases were notified; 814 were confirmed by culture. The proportion of foreign-born cases increased from 33.3% to 39.0%. Foreign-born TB cases were younger (median age, 28 vs. 75 years), and had extrapulmonary TB or multidrug-TB more often than Finnish-born cases (P<0.01 for all comparisons). Foreign-born cases were born in 60 different countries; most commonly in Somalia (25.5%). Altogether 795 isolates were genotyped; 31.2% belonged to 80 different clusters (range, 2-13 cases/cluster). Fourteen (17.5%) clusters included isolates from both Finnish-born and foreign-born cases. An epidemiological link between cases was identified by (epidemiological) background information in two clusters. Although the proportion of foreign-born TB cases was considerable, our data suggests that transmission of TB between foreign and Finnish born population is uncommon.
我们描述了结核病（TB）的流行病学，并对分枝杆菌（M. tuberculosis）分离株进行了特征分析，以评估外国出生和芬兰出生人群之间的传播情况。TB 病例数据来自国家传染病登记处，合法居民及其出生国的分母数据来自人口信息系统。分枝杆菌分离株通过 spoligotyping 和分枝杆菌插入重复单元可变数串联重复（MIRU-VNTR）进行基因分型。我们通过年龄、性别、原籍和居住地区对集群进行了特征描述，其中包括外国出生病例和芬兰出生病例。2014-2017 年期间，共报告了 1015 例 TB 病例，其中 814 例经培养证实。外国出生病例的比例从 33.3%增加到 39.0%。外国出生的 TB 病例更年轻（中位数年龄 28 岁 vs. 75 岁），且更常患有肺外 TB 或耐多药-TB（所有比较均 P<0.01）。外国出生的病例出生于 60 个不同的国家，最常见的是索马里（25.5%）。共有 795 个分离株进行了基因分型，31.2%属于 80 个不同的集群（范围为 2-13 例/集群）。14 个（17.5%）集群包括芬兰出生和外国出生病例的分离株。两个集群的病例通过（流行病学）背景信息确定了病例之间的流行病学联系。尽管外国出生的 TB 病例比例相当大，但我们的数据表明，外国和芬兰出生人群之间的 TB 传播并不常见。
