TY  - JOUR
VL  - 19
ID  - heidok26308
PB  - BioMed Central ; Springer
IS  - 304
AV  - public
N2  - Background: Screening programmes for tuberculosis (TB) among immigrants rarely consider the heterogeneity of risk related to migrants? country of origin. We assess the performance of a large screening programme in asylum seekers by analysing (i) the difference in yield and numbers needed to screen (NNS) by country and WHO-reported TB burden, (ii) the possible impact of screening thresholds on sensitivity, and (iii) the value of WHO-estimated TB burden to improve the prediction accuracy of screening yield.   

Methods: We combined individual data of 119,037 asylum seekers screened for TB in Germany (2002-2015) with TB estimates of the World Health Organization (WHO) (1990-2014) for their 81 countries of origin. Adjusted rate ratios (aRR) and 95% credible intervals (CrI) of the observed yield of screening were calculated in Bayesian Poisson regression models by categories of WHO-estimated TB incidence. We assessed changes in sensitivity depending on screening thresholds, used WHO TB estimates as prior information to predict TB in asylum seekers, and modelled country-specific probabilities of numbers needed to screen (NNS) conditional on different screening thresholds.

Results: The overall yield was 82 per 100,000 and the annual yield ranged from 44.1 to 279.7 per 100,000. Country-specific yields ranged from 10 (95%- CrI: 1-47) to 683 (95%-CrI: 306-1336) per 100,000 in Iraqi and Somali asylum seekers, respectively. The observed yield was higher in asylum seekers from countries with a WHO-estimated TB incidence >?50 relative to those from countries ?50 per 100,000 (aRR: 4.17, 95%-CrI: 2.86-6.59). Introducing a threshold in the range of a WHO-estimated TB incidence of 50 and 100 per 100,000 resulted in the lowest ?loss? in sensitivity. WHO?s TB prevalence estimates improved prediction accuracy for eight of the 11 countries, and allowed modelling country-specific probabilities of NNS.

Conclusions WHO?s TB data can inform the estimation of screening yield and thus be used to improve screening efficiency in asylum seekers. This may help to develop more targeted screening strategies by reducing uncertainty in estimates of expected country-specific yield, and identify thresholds with lowest loss in sensitivity. Further modelling studies are needed which combine clinical, diagnostic and country-specific parameters.
JF  - BMC Infectious Diseases
UR  - https://archiv.ub.uni-heidelberg.de/volltextserver/26308/
EP  - 15
CY  - London ; Berlin, Heidelberg
A1  - Bozorgmehr, Kayvan
A1  - Preussler, Stella
A1  - Wagner, Ulrich
A1  - Joggerst, Brigitte
A1  - Szecsenyi, Joachim
A1  - Razum, Oliver
A1  - Stock, Christian
SP  - 1
TI  - Using country of origin to inform targeted tuberculosis screening in asylum seekers: a modelling study of screening data in a German federal state, 2002-2015
Y1  - 2019///
SN  - 1471-2334
KW  - Tuberculosis
KW  -  Infection control
KW  -  Public health
KW  -  Migration
KW  -  Asylum seekers
KW  -  Screening
KW  -  Efficiency
KW  -  Global health
KW  -  Modelling
KW  -  Epidemiology
ER  -