Search

Background: Drug-resistant tuberculosis (TB) is a global public health issue. To monitor this in Canada, surveillance systems have been in place for the last 20 years., Objective: To describe drug resistance patterns among TB isolates in Canada in 2017 by type of resistance as well as geographic location, demographic data and origin and to compare current data to those of the previous 10 years., Methods: Data were derived and analyzed from two sources. The Canadian Tuberculosis Laboratory Surveillance System (CTBLSS) is an isolate-based laboratory surveillance system and was used to obtain information on the results of drug susceptibility testing (DST) as well as province or territory, sex and age of the individual from which the sample originated. The Canadian Tuberculosis Reporting System (CTBRS) is a case-based surveillance system with information on active and retreatment TB cases in Canada and was used to derive origin data, which is defined as either foreign-born, Canadian-born Indigenous or Canadian-born non-Indigenous. Analysis was descriptive and compared with data from these two sources for 2007-2016., Results: In 2017, 1,515 TB isolates were tested for resistance to anti-TB drugs, with 123 (8.1%) demonstrating resistance to any first-line anti-TB drug. Of these, 103 were monoresistant, six were polyresistant and 14 were multidrug-resistant tuberculosis (MDR-TB). No extensively drug-resistant tuberculosis (XDR-TB) isolates were reported. Drug resistance was reported in seven provinces/territories (British Columbia, Alberta, Saskatchewan, Manitoba, Ontario, Quebec and New Brunswick). There were 63 isolates from females with drug resistance (9.5%) and 60 isolates from males with drug resistance (7.0%). Drug resistance was found in a greater percentage of isolates among those aged 25-34 (n=29, 23.6%). By origin, 1,072 (11%) foreign-born TB cases reported between 2005 and 2015 were drug-resistant. Among the Canadian-born non-Indigenous and Canadian-born Indigenous TB cases, 143 (9%) and 54 (2%) were drug-resistant, respectively. Compared with previous years, the number of isolates tested increased slightly (from 1,267 to 1,515); however, there was a decrease in the percentage of isolates with reported drug resistance (from 10.5% in 2007 to 8.1% in 2017)., Conclusion: In 2017, TB drug resistance rates remained low in Canada., Competing Interests: Conflict of interest: None.Funding: This work was supported by the Public Health Agency of Canada as part of its core mandate.

Background: Tuberculosis (TB) is a major global health problem that affected an estimated 10.4 million people worldwide in 2016. The Public Health Agency of Canada (PHAC) monitors active TB disease through a national surveillance system, which is a collaborative effort withthe provinces and territories., Objective: This article presents an epidemiological summary of the active TB disease cases reported from 2006 to 2016, with a focus on 2016. Treatment outcomes for cases diagnosed in 2015 are also presented., Methods: The Canadian Tuberculosis Reporting System (CTBRS) is a case-based surveillance system that maintains non-nominal data on people diagnosed with active TB disease in Canada. Data are collected annually from the provinces and territories, analyzed by PHAC and validated by each province and territory., Results: The number of active TB disease cases increased from 1,642 in 2015 to 1,737 in 2016, corresponding to an increase in incidence rate from 4.6 to 4.8 per 100,000 population. Foreign born individuals continued to make up the majority of cases reported (70%) and the incidence rate remained highest among Canadian born Indigenous people (23.5 per 100,000 population) and was particularly high within the Inuit population (170.1 per 100,000 population). Over the past decade, there was a slight decrease in the number of cases among children and the proportion of re-treatment cases declined from 8.3% of cases in 2006 to 5.4% of cases in 2016., Conclusion: Although tuberculosis incidence rates in Canada are low in the global context and have been relatively stable over the last decade, there has been a slight increase in rates over the last three years, especially in the foreign born population which accounts for the majority of cases. The decrease in cases among children suggests less active transmission and the low proportion of re-treatment cases suggests effective treatment and adherence., Competing Interests: Conflict of interest: None.

Background: Drug-resistant strains of tuberculosis (TB) pose a serious threat to TB prevention and control efforts. The Canadian Tuberculosis Laboratory Surveillance System (CTBLSS) was created in 1998 to monitor emerging trends and patterns in TB drug resistance in Canada., Objective: To present a descriptive overview of TB drug resistance data collected through the CTBLSS for the years 2006 to 2016 in Canada, with a focus on 2016., Methods: The CTBLSS is an isolate-based surveillance system designed to collect data on TB drug resistance across Canada. Each year, data are collected and analyzed by the Public Health Agency of Canada (PHAC) and then validated by the submitting laboratory., Results: In 2016, anti-tuberculosis drug susceptibility test results were reported for 1,452 isolates. The proportion of TB drug-resistant strains remained relatively stable with 108 (7.4%) of the isolates classified as monoresistant, five (0.3%) isolates as polyresistant and 17 (1.2%) as multidrug-resistant TB (MDR-TB) strains. In 2016, there were no extensively drug-resistant TB (XDR-TB) isolates identified. Males accounted for 792 (54.5%) of all reported isolates and 64 (49.2%) of the resistant strains and females accounted for 11 (64.7%) of the MDR-TB strains. Between 2006 and 2016, individuals between 15 and 44 years of age comprised 47.4% of all reported isolates, 54.0% of isolates showing any resistance and 72.3% of MDR-TB strains., Conclusion: TB drug resistance levels have been relatively low and stable over the past 11 years and have remained below the global average since national surveillance began. However, with growing worldwide concern about drug resistance and the emergence of XDR-TB, the CTBLSS will remain vital to the monitoring of TB drug resistance in Canada., Competing Interests: Conflict of interest: None.