Transcript New Entrant TB Screening

New Entrant TB Screening
Dr. John P. Watson
Consultant Respiratory Physician
New Entrant TB Screening -
Why?
Tuberculosis case reports & rates by place of birth, UK, 2004-2013
98
93
100
91
86
86
84
6,000
84
82
90
81
Number of cases
70
5,000
80
70
60
4,000
50
3,000
40
30
2,000
20
1,000
4
4
4
4
4
4
4
4
4
4
0
0
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
Year
UK born
Non-UK born
Rate UK born
Rate Non-UK born
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
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Tuberculosis in the UK: 2014 report
Rate (per 100,000)
7,000
Tuberculosis case reports & rates by age group & place of birth,
UK, 2013
1,200
100
1,100
90
1,000
80
70
800
700
60
600
50
500
40
400
30
300
20
200
10
100
0
0
Age group (years)
UK Born
Non-UK Born
Rate in UK Born
Rate in Non-UK Born
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
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Tuberculosis in the UK: 2014 report
Rate (per 100,000)
Number of cases
900
New Entrant TB Screening –
How?
Pre-entry CXR
Figure 1.8: Non UK-born tuberculosis case reports by
time since entry to the UK to tuberculosis diagnosis,
UK, 2012
600
Number of cases
500
400
300
200
100
0
0
5
10
15
20
25
30
35
Years since entry to diagnosis
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
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Tuberculosis in the UK: 2013 report
40
45
50+
Proportion of TB case reports by site of disease, UK, 2004-2013
100
Proportion of cases (%)
90
80
70
60
50
40
30
20
10
0
2004
2005
2006
2007
2008
2009
Year
Pulmonary*
2010
2011
Extra-pulmonary only
* With or without extra-pulmonary disease
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
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Tuberculosis in the UK: 2014 report
2012
2013
Limitations
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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
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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
Time between entry to the UK & TB diagnosis for
non-UK born TB cases by year, UK, 2013
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
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Tuberculosis in the UK: 2014 report
TUBERCULOSIS
CXR on arrival?
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Meta-anylsis
TB diagnosis yield by CXR screening
Total TB 0.35%
Continent of origin
Europe 0.24%
 Africa 0.65%
 Asia 1.12%
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Arshad et al. Eur Respir J 2010; 35:1336-1345
LTBI in new entrants
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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?
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Norway 2005-6
912 asylum seekers, 72% BCG
29% Quantiferon Pos
TST ≥ 6mm :
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460(50%)
Detect 88% of Pos IGRA
TST ≥ 15mm:
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141 (15%)
Detect 39% of pos IGRA
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Winje BA et al. BMC Infect Dis. 2008; 8: 65.
New Entrant TB Screening -
Who?
New Entrants:
Who to screen for LTBI?
NICE 2006
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Children
Pregnant women
Sub-Saharan Africa
East Timor
NICE 2006: CG33
Problems with NICE 2006:
Who to screen?
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LTBI testing limited to Africa (+East Timor)
TB incidence Gambia: 173/105
 TB incidence Philippines: 292/105
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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
Country of birth
India
Pakistan
Somalia
Bangladesh
Nepal
Nigeria
Philippines
Zimbabwe
Sri Lanka
Kenya
Romania
Afghanistan
Poland
Eritrea
China
Others (each
<1%)
Total*
Number of cases
Percentage
of cases*
Median time since
entry to UK (IQR)**
1,615
1,103
292
248
170
164
136
105
95
84
70
67
66
62
56
29.8
20.4
5.4
4.6
3.1
3.0
2.5
1.9
1.8
1.6
1.3
1.2
1.2
1.1
1.0
5 (2 -13)
7 (2 -22)
9 (4 -13)
7 (3 -18)
3 (2 -6)
7 (3 -11)
8 (5 -12)
11 (7 -12)
7 (3 -13)
22 (8 -37)
2 (0 -4)
6 (2 -11)
5 (2 -7.5)
4 (2 -7)
7 (4 -11)
1,082
20.0
5 (1 -13)
5,415
100
7 (3 -14)
* Where country of birth was known; **Years
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
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Tuberculosis in the UK: 2014 report
New Entrants:
Who to screen for LTBI?
NICE 2011
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“High incidence countries”
Defined in NICE as >40/100,000
NICE 2011: CG117
Problems with NICE 2011:
Who to screen?
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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?
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Yield low – is it cost effective?
The problem in Leeds - 2006
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Rising incidence of TB, predominantly among
arrivals to UK in previous 2-3 years
NICE guidance for new entrant Xrays
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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
16000
Number of Registrations
14000
All Countries
12000
10000
Countries w ith TB Incidence >40 per
100,000
8000
Countries w ith TB Incidence >160 per
100,000
6000
4000
2000
0
2000
2001
2002
2003
2004
Year
2005
2006
2007
TB
SCREENING
2007 Leeds Pilot
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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
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Number screened
LTBI diagnosed
active TB
Total cost
Cost per LTBI diagnosed
Leeds
280
105
0
£9 781
£93.18
NICE 2006
275
83*
0
£13 346
£160.81*
*Assuming no false negative TST
Hardy et al, Thorax 2010;65:178-80
Leeds 2008 - 2012
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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%
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Audit of 184 patients in 2009
Problem – high rate of non attendance for
screening
Yield of IGRA for new entrant
screening
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Multicentre study
“Real life” screening situation 2009
Leeds, Westminster, Blackburn
New entrants, screened with IGRA
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QuantiFERON TB Gold In Tube
Pareek M, et al. Lancet Infect Dis 2011;11:435-44.
Results
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Total screened:
Age
<16 36
 16-25 589
 26-35 604
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1229
( 3%)
(48%)
(49%)
Female:
Previous BCG:
Indian subcontinent:
Sub-Saharan Africa:
51%
83%
60%
20%
Results (continued)
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IGRA Results
Positive
 Negative
 Indeterminate
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245
982
2
Positive result associated with:
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Increasing TB incidence in country of origin
(p<0.01)
TB incidence <150/105 : 13%
 TB incidence >150/ 105: 21.5%
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(20%)
(80%)
(0.2%)
Increasing age (p<0.0001)
Active TB: 5 cases.
Cost effectiveness
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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.
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Detect 92% positive IGRA
NICE 2006 protocol would miss 71% of LTBI
Assumptions for cost calculations
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Pos Quantiferon – untreated has 5% risk of TB
within 20 years
Chemoprophylaxis reduces risk by 60%
BUT
The Big But
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Blackburn 1989-2001 New entrants 16-34 yr
with pos TST: 16% active TB after 15 years
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Norway asylum seekers:
Pos QFT: Active TB 3.3% in 23-32 months
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Choudhury et al, Public Health 2014;36:390-5
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?
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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
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New Entrants:
When to screen?
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At airport
Experience of port of entry CXR not promising
 Follow up of results?
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Asylum seekers: reception centre
On arrival in destination place of residence
GP registration
 Social Housing / school entry/ work permit /
university registration
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New Entrant TB Screening:
Conclusions
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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
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But can it make a difference?
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