1. End TB strategy target setting
Philippe Glaziou
Manila, December 2014

2. Outline Rationale for global projections post-2015
TB burden assessment
Country targets
Short-term (3-5 years)
Long-term (≥10 years)

3. Decline in TB burden in England and Wales
TB mortality
TB incidence
-3%/year

4. CFR in England and Wales Global CFR : 1
CFR in England and Wales Global CFR : 1.5 million deaths / 9 million incident
Chemotherapy introduced
Global CFR in 2013

5. Slow decline in global incidence, faster decline in mortality
Mortality (including HIV)
Falling 2% per year ( )
Falling 4.7% per year ( )

6. Why is global TB incidence declining so slowly?

7. Average lifetime risk of disease 5- 15%*
World 7 billion
Disease ≈9 million/yr
Infected ≈2.3 billion
*Am J Epidemiol Vol. 152, No. 3, 2000

8. Tools required for mitigating infection
Mass Screening and Treatment may stop transmission but not TB reactivation
Mass Prophylactic Treatment
IPT prevents 70% of reactivation in HIV-neg Safety on a mass scale? (4-7/100,000 fatal hepatitis) Millard PS et al. West J Med Jun;164(6):
Mass Post-Exposure Vaccination

9. Business as usual
-2%/year
Global TB incidence rate

10. Optimize use of current tools, universal access, social protection
-2%/year
Business as usual
-10%/year
-5%/year

11. R&D pipelines No point of care test yet
2 new drugs, little epi impact anticipated
15 vaccines in development
New vaccine not likely until 2024 (AERAS)

12. Beyond 2025 Potential impact of vaccine Introduced in 2025
60% post-exposure efficacy
95% coverage reached after 10 years
Assess year by which epidemic of TB could be "ended"
TB disease ~2
7+ billion

13. Technological breakthrough by 2025 addresses the pool of infection
-2%/yr
Business as usual
-10%/yr
Optimize current tools
-5%/yr
Post-exposure vaccine ± safe PT
-17%/yr
"End the global TB epidemic"

14. Goal: End the global TB epidemic
2025 and 2035 TB targets
Goal: End the global TB epidemic
TB deaths
TB incidence
Rate per 100,000 population
Millions
-75% vs. 2015
-95% vs. 2015
10 per 100,000

15. Estimating TB incidence
National incidence surveys impractical
Best documented through state-of-the art TB surveillance. Estimates are uncertain due to
Under-reporting
Under-diagnosis
Estimation from tuberculin surveys not satisfactory
Prevalence surveys

16. Capture-recapture in Iraq
1980 detected, under-reporting = 16%
473 additional cases estimated (394–565)

17. How else can we estimate incidence?
From results of prevalence surveys

18. Method 1 – deterministic model
Untreated
Treated
mortality
cure

19. Method 1 π ~ U (0, 0.1) 300 79 6.1 (5-7.5) 1.8 (1.1-1.6) 3.3 (2-4.8)
Prevalence
(per 1000)
Duration
(year)
Incidence
(per 1000/yr)
Myanmar 2009
300 79
6.1 (5-7.5)
1.8 ( )
3.3 (2-4.8)
Thailand 2012
136 60
2.5 ( )
1.1 ( )
2.3 (1-3.5)
Indonesia 2013
407
122
6.6 (5.2 – 8.1)
1.6 (1 – 2.2)
4.1 (2.4 – 5.8)

20. Method 2
Reverse WHO method to estimate prevalence from incidence based on standard assumptions about disease duration (4 case categories)
Notified HIV- ~U ( ) year
Not notified HIV- ~U (1 - 4) year
Notified HIV+ ~U (0.01 – 1) year
Not notified HIV+ ~U (0.01 – 0.2) year

21. Incidence in Indonesia (2013), ensemble model
Ensemble 402 ( ) per 100,000/year
Method 1 (dynamic)
Method 2 (duration)

22. Data on TB deaths (HIV-) from vital registration
74 countries with no reliable data on causes of deaths
38 other countries with low-quality data

23. Sources of data Best sources of data on TB burden are
TB notifications when data meet quality criteria and under-reporting low and documented
TB mortality from Vital Registration with COD
Prevalence from national prevalence surveys
Impact assessment methods tailored to the existing data
2015: meeting the WHO task force on TB impact measurement to review methods to evaluate the 2015 targets achievement

24. Short-term targetting (3-5 years)
Monitor progress towards set target
Use a directly measured indicator
Not incidence, not CDR, because in most cases it will not be possible to state whether the country is on track
Mortality if Vital Registrations or sample VR
Prevalence if repeat survey within the programme cycle
Case notifications
Treatment success

25. Adaptation at country level
Short-term targets ( )
Based on a thorough epi analysis, standards and benchmarks for surveillance
Assessment of planned actions
Long-term targets (2025, 2035)
Project incidence and CFR over time
Target for catastrophic cost achieved if universal access is achieved

26. In conclusion Ambitious post-2015 global targets
Country adoption of targets:
Evaluate surveillance system
Projections
Short-term, programme planning based on measurable indicators
Long-term, based on indicators that will become measurable
Acceleration of the decline in incidence
Improvements over the case fatality ratio (% of incident cases who die from TB)  faster decline of TB mortality