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The Challenges Facing Tuberculosis Control
Blantyre Hospital, Malawi: TB Division,
3 patients per bed
Health Organization
The Burden of Tuberculosis, 2009


9.27 million new cases in 2007, 80% in 22 high-burden
countries
1.75 million deaths in 2007 and 98% of these in the developing
world

0.45 million deaths due to TB/HIV

0.5 million Multi-drug resistant TB (MDRTB) in 2007
Estimated TB Incidence Rates
Rate per 100 000
0-9
10 - 24
25 - 49
50 - 99
100 - 300
300 or more
No Estimate
Incidence rates stable or falling slowly
400
Cases per 100,000 population
350
300
250
10
8
6
4
2
0
Cases in millions
9.15
Africa
South-East Asia
WORLD
200
Western Pacific
150
100
Eastern
Mediterranean
Europe
50
Americas
0
Incidence Rate trend of pulmonary TB in Saudi Arabia
(per 100000) 1999 – 2008
Global TB Control Targets
2015: Goal 6: Combat HIV/AIDS, malaria and other diseases
Target 8:
Indicator 23:
Indicator 24:
to have halted by 2015 and begun to reverse the
incidence…
incidence, prevalence and deaths associated with TB
proportion of TB cases detected
and cured under DOTS
2015: 50% reduction in TB prevalence and deaths by 2015
2050: elimination (<1 case per million population)
The DOTS Strategy (1994)
• Government commitment to TB control
• Case detection primarily by smear microscopy mostly
on self-reporting symptomatic patients
• Standardised short-course chemotherapy under
proper case management conditions, including DOT
• System of regular drug supply
• Efficient monitoring system for programme
supervision and evaluation
DOTS and overall SS+ case detection
a flattening curve
80
2.5 million
detected and
notified out
of 4.1 million
estimated
all notified
DOTS
60
40
100
80
60
40
20
0
20
77 69
67
52 52 46
Global Plan:
65% in 2006
78% by 2010
0
1990
1995
2000
2005
2010
The gaps in basic TB control!
• Not all TB cases are detected
• Not all TB cases are detected
early enough
• Not all TB cases are treated
• Not all TB cases are treated
well enough
What are the key challenges to
increasing case detection?
• About 40% (3 – 5.6 M) of estimated cases
are not notified (and not diagnosed?)
• Are the cases not notified or not identified?
 Identified but not notified: in health sector but

not in DOTS providers
Not notified because not identified : informal
care providers, home, etc….
The Challenges Facing TB Control
• Delay in detection of pulmonary TB
-difficult access to HC services
- Lack of awareness about TB
- Fear
• Delay in reporting TB Cases
The Challenges Facing TB Control
• Deficiencies in protecting contacts
- Variations in contact investigation
- Difficulties in finding contacts
• Inappropriate or inadequate therapy
• Failure to complete therapy (defaults)
The Challenges Facing TB Control
• Imported TB
- Immigrants from high burden countries
- More delay in TB detection
- Impact of social factors
• Pool of latent TB
- Risk of reactivation is 10% in a lifetime
- In normal individuals: risk is 0.1% per year
- Risk is more with impaired immunity
Impact of HIV on TB


Direct:
 Reactivation of TB infection acquired before HIV
infection (from 10% lifetime to 3-13%/year)
 Rapid progression of TB infection acquired after HIV
infection
Indirect:
 Transmission to the population not infected with HIV
World Health Organization
MDR-TB: Global Rates
• Resistance to both INH & Rifampicin
• Increasing rate
2002 : 272,900 (1.1%)
2007 : 510,500 (4.9%)
• Estimated 43% of global MDR-TB cases have had prior
treatment
• China, India and Russian Federation accounts for 62% of
the MDR burden
Transmission of TB
•
•
•
•
•
•
Almost always by airborn route
Indoors: TB bacilli remain suspended in air for hours
At diagnosis ; 30 – 40% of contacts have +ve PPD
Infection is dependent on duration of exposure
Infection more likely in close contacts of SS+ patients
Infectiousness rapidly decreases shortly after starting
multiple drug therapy
Facing the challenges
• Early detection and treatment of TB cases:
- Easy access to health care
- Increase awareness of TB among HC workers
- Availability of diagnostic facilities
- Availability of effective chemotherapy
- Ensuring adherence to standard practice
Facing the challenges
• Reduce incidence of TB among high risk groups:
- Contacts of TB patients
- Immigrants from high burden countries
- Prisoners
- Immunocompromised
• Address MDR TB and HIV
• Surveillance and monitoring of outcome
• Engaging all health care providers
• Promoting research
Is TB elimination possible?
• Slow incidence rate decline
• Need Substantial advances in diagnosis and therapy:
- Better diagnostic tests for TB and latent TB
- More effective drugs for treatment
- Better vaccines for prevention
Impact of drug resistance on TB cure rates with standard 4-drug
therapy
% Success
New Case Retreated
Pan-susceptible
Any resistance, not MDR
INH resistance, not MDR
RIF resistance, not MDR
MDR
Espinal, JAMA 2000; 283:2537
85
81
82
73
52
67
56
54
53
29
Global Strategy to Stop TB 2006-2015
1.
Pursuing quality DOTS expansion and enhancement
•
•
•
•
•
Government commitment with long-term planning and adequate resources to reach
targets
Case detection through bacteriology and strengthening of laboratory network
Standardised treatment, under proper case management conditions including DOT and
patient support
Effective and regular drug supply system
Monitoring system for supervision and evaluation, including impact measurement
Additional components
2
Addressing TB/HIV and MDR-TB
3.
Contributing to health system strengthening
4.
Engaging all care providers
5.
Empowering patients and communities
6.
Enabling and promoting research
World Health Organization