Dataset Information

Is there a fundamental flaw in Canada's post-arrival immigrant surveillance system for tuberculosis?

ABSTRACT:

Background

New immigrants to Canada with a history of tuberculosis or evidence of old healed tuberculosis on chest radiograph are referred to public health authorities for medical surveillance. This ostensible public health protection measure identifies a subgroup of patients (referrals) who are at very low risk (compared to non-referrals) of transmission.

Methods

To assess whether earlier diagnosis or a different phenotypic expression of disease explains this difference, we systematically reconstructed the immigration and transmission histories from a well-defined cohort of recently-arrived referral and non-referral pulmonary tuberculosis cases in Canada. Incident case chest radiographs in all cases and sequential past radiographs in referrals were re-read by three experts. Change in disease severity from pre-immigration radiograph to incident radiograph was the primary, and transmission of tuberculosis, the secondary, outcome.

Results

There were 174 cohort cases; 61 (35.1%) referrals and 113 (64.9%) non-referrals. Compared to non-referrals, referrals were less likely to be symptomatic (26% vs. 80%), smear-positive (15% vs. 50%), or to have cavitation (0% vs. 35%) or extensive disease (15% vs. 59%) on chest radiograph. After adjustment for referral status, time between films, country-of-birth, age and co-morbidities, referrals were less likely to have substantial changes on chest radiograph; OR 0.058 (95% CI 0.018-0.199). All secondary cases and 82% of tuberculin skin test conversions occurred in contacts of non-referrals.

Conclusions

Phenotypically different disease, and not earlier diagnosis, explains the difference in transmission risk between referrals and non-referrals. Screening, and treating high-risk non-referrals for latent tuberculosis is necessary to eliminate tuberculosis in Canada.

SUBMITTER: Long R

PROVIDER: S-EPMC6407769 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Is there a fundamental flaw in Canada's post-arrival immigrant surveillance system for tuberculosis?

Long Richard R Asadi Leyla L Heffernan Courtney C Barrie James J Winter Christopher C Egedahl Mary Lou ML Paulsen Catherine C Kunimoto Brenden B Menzies Dick D

PloS one 20190308 3

<h4>Background</h4>New immigrants to Canada with a history of tuberculosis or evidence of old healed tuberculosis on chest radiograph are referred to public health authorities for medical surveillance. This ostensible public health protection measure identifies a subgroup of patients (referrals) who are at very low risk (compared to non-referrals) of transmission.<h4>Methods</h4>To assess whether earlier diagnosis or a different phenotypic expression of disease explains this difference, we syste ...[more]

PMID: 30849130

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Project description:BackgroundInternational migration rapidly increased in the last decade, raising a renewed attention to its impact on public health. We evaluated differences in rubella immunization rate (RIR) between immigrant and Italian women of childbearing age and tried to identify the driving factors causing them.MethodsWe analyzed data from the Italian behavioral surveillance system PASSI collected in 2011-2015 in a nationally representative sample of residents in Italy. The analysis was performed using log-binomial models to compare RIR between 41,094 Italian women and 3140 regular immigrant women of childbearing age (18-49 years), stratifying the latter by area of origin and length-of-stay in Italy (recent: ? 5-years; mid-term: 6-10-years; long-term: > 10-years).ResultsImmigrant women showed a RIR of 36.0% compared to 60.2% among Italian women (RIR-ratio = 0.60, 95% confidence interval (CI): 0.57-0.63). Adjusting for demographic characteristics (i.e., sex, age and area of residence), socio-economic factors (i.e., education, occupation, family composition and economic status) and an indicator of the presence of at least one health-risk behavior (i.e., physical inactivity, current cigarette smoking, excessive alcohol consumption and excess weight) did not significantly change this difference (RIR-ratio = 0.56, 95% CI: 0.53-0.59). Recent immigrants (RIR-ratio = 0.47, 95% CI: 0.42-0.53) and immigrants from high migratory pressure countries (HMPC) in sub-Saharan Africa (RIR-ratio = 0.41, 95% CI: 0.31-0.56) and Asia (RIR-ratio = 0.42, 95% CI: 0.33-0.53) showed the greatest differences in RIR compared with Italian women.ConclusionsDifferences in RIR between immigrant and Italian women were not explained by different demographic, socioeconomic and health-risk behaviors characteristics. As entitlement to free-of-charge immunization in Italy is universal, regardless of migration status, other informal barriers (e.g., cultural and barriers to information access) might explain lower RIRs in immigrant women, especially recent immigrants and those from HMPC in sub-Saharan Africa and Asia. Further investigations are needed to identify obstacles and appropriate promotion and access-enabling strategies for rubella immunization.

Dataset Information

Is there a fundamental flaw in Canada's post-arrival immigrant surveillance system for tuberculosis?

Background

Methods

Results

Conclusions

Publications

Is there a fundamental flaw in Canada's post-arrival immigrant surveillance system for tuberculosis?

Similar Datasets

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