Latent tuberculosis may be missed by current screening practices: Analysis of interferon-gamma release assay results from a paediatric refugee clinic

Towards elimination of childhood and adolescent tuberculosis in the Netherlands: an epidemiological time-series analysis of national surveillance data

BACKGROUND

Tuberculosis (TB) in children and adolescents is a sentinel event for ongoing transmission. In the Netherlands, epidemiological characteristics of childhood and adolescent TB have not been fully evaluated. Therefore, we aimed to assess TB epidemiology within this population to provide guidance for TB elimination.

METHODS

A retrospective time-series analysis using national surveillance data from 1993-2018 was performed in children (aged <15 years) and adolescents (aged 15-19 years) with TB. Poisson regression models offset with log-population size were used to estimate notification rates and rate ratios. Trends in notification rates were estimated using average annual percentage changes (AAPC) based on the segmented linear regression analysis.

RESULTS

Among 3899 children and adolescents with TB notified during 1993-2018, 2418 (62%) were foreign-born (725 (41.3%) out of 1755 children and 1693 (78.9%) out of 2144 adolescents). The overall notification rate in children was 2.3 per 100 000 person-years, declining steadily during the study period (AAPC -10.9%, 95% CI -12.6--9.1). In adolescents, the overall notification rate was 8.4 per 100 000 person-years, strongly increasing during 1993-2001 and 2012-2018. Compared to Dutch-born children and adolescents, substantially higher notification rates were observed among African-born children and adolescents (116.8 and 316.6 per 100 000 person-years, respectively). Additionally, an increasing trend was observed in African-born adolescents (AAPC 18.5%, 95% CI 11.9-25.5). Among the foreign-born population, those from countries in the horn of Africa contributed most to the TB caseload.

CONCLUSION

TB notification rate among children was low and constantly declining across different demographic groups. However, heterogeneities were shown in adolescents, with an increasing trend in the foreign-born, particularly those from Africa.

Tuberculosis infection in under-2-year-old refugees: Should we be screening? A systematic review and meta-regression analysis

AIM

Refugees are at increased risk of tuberculosis infection due to time spent in crowded camps, decreased nutrition and originating from countries whose own tuberculosis control systems may have been disturbed. In Australia, tuberculosis is screened for in for all refugees aged 11-34 years old and in those aged 2-10 years arriving from high-incidence countries. Our aims were to determine if refugee children aged under 2 years of age should also be screened.

METHODS

A systematic literature review and meta-regression was carried out on studies in refugee children under 18 years old, involving screening for tuberculosis (active or latent tuberculosis infection (LTBI)). Studies were extracted from the last 10 years from a range of bibliographic databases using the search terms 'tuberculosis', 'children', 'screening' and 'refugee', which tested for tuberculosis using the tuberculin skin test (TST) or QuantiFERON-Gold (Interferon Gamma Release Assay (IGRA)).

RESULTS

Of the 15 included studies, prevalence of LTBI in < 2-year-olds was 5% using IGRA and 15% using TST (P < 0.05). Prevalence increased with age (odds ratio 1.12; 95% confidence interval: 1.06-1.17) cumulatively and decreased where IGRA was used for screening compared to TST (odds ratio 0.38; 95% confidence interval: 0.25-0.58). Prevalence of LTBI did not differ between general versus clinic refugee cohorts.

CONCLUSIONS

Refugees are a particularly vulnerable group in their susceptibility to tuberculosis, and LTBI management is a critical part of tuberculosis disease control due to the lifetime risk of developing active tuberculosis. A prevalence of 5-15% for LTBI in the under 2 years age group would support them being included in screening programmes.