Time for a preventative strategy for TB in the UK: further evidence for new entrant screening in primary care

Outcomes analysis of new entrant screening for active tuberculosis in Heathrow and Gatwick airports, United Kingdom 2009/2010

Background

In 2012, the United Kingdom (UK) Government announced that the new entrant screening for active tuberculosis (TB) in Heathrow and Gatwick airports would end. Our study objective was to estimate screening yield and diagnostic accuracy, and identify those at risk of active TB after entry.

Methods

We designed a retrospective cohort study and linked new entrants screened from June 2009 to September 2010 through probabilistic matching with UK Enhanced TB Surveillance (ETS) data (June 2009 to December 2010). Yield was the proportion of cases reported to ETS within three months of airport screening in the screened population. To estimate screening diagnostic accuracy we assessed sensitivity, specificity, positive and negative predictive values. Through Poisson regression we identified groups at increased risk of TB diagnosis after entry.

Results

We identified 200,199 screened entrants, of these 59 had suspected TB at screening and were reported within 3 months to ETS (yield = 0.03 %). Sensitivity was 26 %; specificity was 99.7 %; positive predictive value was 13.2 %; negative predictive value was 99.9 %. Overall, 350 entrants were reported in ETS. Persons from countries with annual TB incidence higher than 150 cases per 100,000 population and refugees and asylum seekers were at increased risk of TB diagnosis after entry (population attributable risk 77 and 3 % respectively).

Conclusion

Airport screening has very low screening yields, sensitivity and positive predictive value. New entrants coming from countries with annual TB incidence higher than 150 per 100,000 population, refugees and asylum seekers should be prioritised at pre- or post-entry screening.

Low rate of non-compliance to antituberculous therapy under the banner of directly observed treatment short course (DOTS) strategy and well organized retrieval system: a call for implementation of this strategy at all DOTS centers in Saudi Arabia

Introduction

The objective of this study was to show the effectiveness of revised retrieval system on non-compliance.

Methods

We retrospectively evaluated the effectiveness of a revised retrieval system on non-compliance during continuous phase of antituberculous treatment (Jan-2005 to Dec-2010) compared to baseline non-compliance (Jan-2002 to Dec-2004).

Results

In the baseline period, 141 of 501 (28%) patients did not attend their first appointment. Of these 141 patients, 63 (45%) patients could be brought back to treatment while 78 patients (16%) dropped out and could not be retrieved. During the 2nd phase after launching a revised retrieval system, 98 of 835 (13%) patients did not attend their first appointment. Using the retrieval system, 79 (81%) patients were brought back for regular follow up, and 19 patients could not be retrieved, a dropout rate of 2.27%. By virtue of revised retrieval system, there was a significant drop in non-compliance by 15% and a decline in net dropout rate by 14%. The number of those brought back to treatment by revised retrieval system almost doubled (81%) compared to 44% retrieval in initial period.

Conclusion

The revised retrieval system had a significant impact on the reduction of dropout rate and significant improvement in the retrieval of those patients.