New Entrant TB Screening Dr. John P. Watson Consultant Respiratory Physician.
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Transcript of New Entrant TB Screening Dr. John P. Watson Consultant Respiratory Physician.
New Entrant TB Screening
Dr. John P. WatsonConsultant Respiratory Physician
New Entrant TB
Screening - Why?
3
Tuberculosis case reports & rates by place of birth, UK, 2004-2013
Tuberculosis in the UK: 2014 report
Source: Enhance Tuberculosis Surveillance (ETS), Enhanced Surveillance of Mycobacterial Infections (ESMI), Labour Force Survey (LFS)Data as at: May 2014. Prepared by: TB Section, Centre for Infectious Disease Surveillance and Control, Public Health England
2004 2005 2006 2007 2008 2009 2010 2011 2012 20130
1,000
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6,000
7,000
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4 4 4 4 4 4 4 4 4 4
9398
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84 86 86 8284
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UK born Non-UK born Rate UK born Rate Non-UK born
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0-4
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30-3
435
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UK Born Non-UK Born Rate in UK Born Rate in Non-UK Born
Age group (years)
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Tuberculosis case reports & rates by age group & place of birth, UK, 2013
Tuberculosis in the UK: 2014 report
Source: Enhance Tuberculosis Surveillance (ETS), Enhanced Surveillance of Mycobacterial Infections (ESMI),Labour Force Survey (LFS)Data as at: May 2014. Prepared by: TB Section, Centre for Infectious Disease Surveillance and Control, Public Health England
New Entrant TB
Screening – How?
Pre-entry CXR
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0 5 10 15 20 25 30 35 40 45 50+
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Years since entry to diagnosis
Figure 1.8: Non UK-born tuberculosis case reports by time since entry to the UK to tuberculosis diagnosis, UK, 2012
Source: Enhanced Tuberculosis Surveillance (ETS), Enhanced Surveillance of Mycobacterial Infections (ESMI)
Data as at July 2013
Prepared by: TB Section, Centre for Infectious Disease Surveillance and Control, Public Health England
7 Tuberculosis in the UK: 2013 report
8
Proportion of TB case reports by site of disease, UK, 2004-2013
* With or without extra-pulmonary disease
Tuberculosis in the UK: 2014 report
Source: Enhance Tuberculosis Surveillance (ETS), Enhanced Surveillance of Mycobacterial Infections (ESMI)Data as at: May 2014. Prepared by: TB Section, Centre for Infectious Disease Surveillance and Control, Public Health England
2004 2005 2006 2007 2008 2009 2010 2011 2012 20130
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Pulmonary* Extra-pulmonary onlyYear
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Limitations
500 diagnosed within 1 year of arrival
52% pulmonary = 260 cases detectable by CXR – assuming that CXR abnormal up to 12 months before presentation with symptoms.
UK total 7892 cases in 2013 At best, reduce incidence by 3.3%
Yield of pre-entry screening
70-80 cases of TB detected per year 2013 increased to 130 Rate 188/100,000 (0.19%)
Public Health England: Tuberculosis in the UK: 2014 report
11
Time between entry to the UK & TB diagnosis for non-UK born TB cases by year, UK, 2013
Tuberculosis in the UK: 2014 report
Source: Enhance Tuberculosis Surveillance (ETS), Enhanced Surveillance of Mycobacterial Infections (ESMI), Office for National Statistics (ONS)Data as at: May 2014. Prepared by: TB Section, Centre for Infectious Disease Surveillance and Control, Public Health England
TUBERCULOSIS
CXR on arrival?
Meta-anylsis TB diagnosis yield by CXR screening Total TB 0.35% Continent of origin
Europe 0.24% Africa 0.65% Asia 1.12%
Arshad et al. Eur Respir J 2010; 35:1336-1345
LTBI in new entrants
Most TB in overseas born Most have been here > 1 year –
opportunity to identify LTBI before develop active disease
Most in age group eligible for chemoprophylaxis
Screening for LTBI - how
TST IGRA
2 step test: TST, followed by IGRA if positive to improve specificity
Which test for LTBI in new entrants?
Norway 2005-6 912 asylum seekers, 72% BCG 29% Quantiferon Pos TST ≥ 6mm :
460(50%) Detect 88% of Pos IGRA
TST ≥ 15mm: 141 (15%) Detect 39% of pos IGRA
Winje BA et al. BMC Infect Dis. 2008; 8: 65.
New Entrant TB
Screening - Who?
New Entrants: Who to screen for LTBI?
NICE 2006
Children Pregnant women Sub-Saharan Africa East Timor
NICE 2006: CG33
Problems with NICE 2006: Who to screen?
LTBI testing limited to Africa (+East Timor) TB incidence Gambia: 173/105
TB incidence Philippines: 292/105
Largest number of TB cases in UK in overseas born from Asia. 42% Pakistan, India & Bangladesh <50% from Africa
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Most frequent countries of birth for non-UK born TB cases, UK, 2013
* Where country of birth was known; **Years
Country of birth Number of cases
Percentage of cases*
Median time since entry to UK (IQR)**
India 1,615 29.8 5 (2 -13)
Pakistan 1,103 20.4 7 (2 -22)
Somalia 292 5.4 9 (4 -13)
Bangladesh 248 4.6 7 (3 -18)
Nepal 170 3.1 3 (2 -6)
Nigeria 164 3.0 7 (3 -11)
Philippines 136 2.5 8 (5 -12)
Zimbabwe 105 1.9 11 (7 -12)
Sri Lanka 95 1.8 7 (3 -13)
Kenya 84 1.6 22 (8 -37)
Romania 70 1.3 2 (0 -4)
Afghanistan 67 1.2 6 (2 -11)
Poland 66 1.2 5 (2 -7.5)
Eritrea 62 1.1 4 (2 -7)
China 56 1.0 7 (4 -11) Others (each <1%)
1,082 20.0 5 (1 -13)
Total* 5,415 100 7 (3 -14)
Tuberculosis in the UK: 2014 report
Source: Enhance Tuberculosis Surveillance (ETS), Enhanced Surveillance of Mycobacterial Infections (ESMI)Data as at: May 2014. Prepared by: TB Section, Centre for Infectious Disease Surveillance and Control, Public Health England
New Entrants: Who to screen for LTBI?
NICE 2011 “High incidence countries” Defined in NICE as >40/100,000
NICE 2011: CG117
Problems with NICE 2011:
Who to screen? Logic of 40/100,000 threshold
People moving from Libya (TB incidence 40/105) to London (TB incidence 44.4/105) should be screened
Should we screen all “immigrants” to Yorkshire or Manchester from London?
Yield low – is it cost effective?
The problem in Leeds - 2006
Rising incidence of TB, predominantly among arrivals to UK in previous 2-3 years
NICE guidance for new entrant Xrays Massive resource implication
Lack of logic in who to screen for LTBI
GP registrations: 6-8x more new entrants than previously identified by Port Health.
No increase in resources
Rising Immigration
New Immigrants Registering with GP in Leeds 2000 - 2007
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Countries w ith TB Incidence >40 per100,000
Countries w ith TB Incidence >160 per100,000
TBSCREENIN
G
2007 Leeds Pilot
Limit to countries with TB incidence >200
No TST except children Nurse led community based clinic Simple symptom questions + QFT
for all >16yrs QFT neg – informed by letter, no
further action QFT pos - invited for CXR and
medical review If no active TB, <35 – Rx for LTBI
Leeds immigrant screening results 2007
Leeds NICE 2006
Number screened 280 275 LTBI diagnosed 105 83* active TB 0 0 Total cost £9 781 £13 346 Cost per LTBI diagnosed £93.18 £160.81*
*Assuming no false negative TST
Hardy et al, Thorax 2010;65:178-80
Leeds 2008 - 2012 Based on 2007 pilot New Entrants identified by GP
registration data Funding improved to move threshold
down to 160/100,000 to include India and Pakistan
Screened 2884 684 (23.7%) IGRA positive Chemoprophylaxis completion rate
89% Audit of 184 patients in 2009
Problem – high rate of non attendance for screening
Yield of IGRA for new entrant screening
Multicentre study “Real life” screening situation 2009 Leeds, Westminster, Blackburn New entrants, screened with IGRA
QuantiFERON TB Gold In Tube
Pareek M, et al. Lancet Infect Dis 2011;11:435-44.
Results
Total screened: 1229 Age
<16 36 ( 3%) 16-25 589 (48%) 26-35 604 (49%)
Female: 51% Previous BCG: 83% Indian subcontinent: 60% Sub-Saharan Africa: 20%
Results (continued)
IGRA Results Positive 245 (20%) Negative 982 (80%) Indeterminate 2 (0.2%)
Positive result associated with: Increasing TB incidence in country of
origin (p<0.01) TB incidence <150/105 : 13% TB incidence >150/ 105: 21.5%
Increasing age (p<0.0001) Active TB: 5 cases.
Cost effectiveness
Couuntries with TB incidence> 150/105 ICER £20,819 per case prevented
More effective and less cost than NICE 2006
150/105 prevents more disease than higher threshold. Detect 92% positive IGRA
NICE 2006 protocol would miss 71% of LTBI
Assumptions for cost calculations
Pos Quantiferon – untreated has 5% risk of TB within 20 years
Chemoprophylaxis reduces risk by 60%
BUT
The Big But Blackburn 1989-2001 New entrants
16-34 yr with pos TST: 16% active TB after 15 years
Choudhury et al, Public Health 2014;36:390-5
Norway asylum seekers: Pos QFT: Active TB 3.3% in 23-32 months
Winje BA et al. BMC Infect Dis. 2008; 8: 65.
ERS 2014 new data
If 15% Active TB after 20 years
cost to prevent 1 case of TB: not £20,819, but……
£3,040
LTBI
New Entrant TB
Screening - When?
New Entrants: When to screen?
As soon as possible! Before leaving home country?
Problem of adequate resources for testing and treatment
Verification of test results / treatment Distorts priority in high burden
countries from case finding and holding of active TB
Risk of reinfection prior to travel to UK Not practical for asylum seekers / war
zones
New Entrants: When to screen?
At airport Experience of port of entry CXR not
promising Follow up of results?
Asylum seekers: reception centre On arrival in destination place of
residence GP registration Social Housing / school entry/ work
permit / university registration
New Entrant TB Screening:
Conclusions Why: Top reduce the incidence of TB
in UK Who: New entrants from countries
with TB incidence > 150/105
How: Single step IGRA When: As soon as possible after
arrival in UK
But can it make a difference?
?