Prevention of Tuberculosis in Kuwait

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Transcript Prevention of Tuberculosis in Kuwait

Prevention of Tuberculosis
in Kuwait
Samir M. Bahnasy, MBBCh,, MSc TMH, DPH, Dr PH,
Consultant Epidemiologist
Talk outline
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Background
Descriptive Epidemiology
Epidemiological Statistics
Prevention
Prospective achievements
Background
Tuberculosis is one of the oldest diseases
known to affect man. It might involve almost any
part of the body, though to a variable extent,
pulmonary type is the most frequent.
Pulmonary tuberculosis represents an
important global health problem due to its close
relation to the socio-economic standard of the
population, chronic nature, and the need for longterm treatment. It represents the most important
form as it is the most common one and patients
with pulmonary tuberculosis are the principal
sources of other forms of tuberculosis infection.
Background
In the beginning of l980s, tuberculosis was so well
controlled in developed countries. The progressive
decline in the incidence of tuberculosis suggested
that eradication of the disease was possible.
However in 1985, the steady annual decrease in
the number of cases leveled off, and then the rate
began to rise.
This upside-down change might be attributed to
a range of factors such as the pandemic of (HIV)
infection, population growth, migration,
Background
socioeconomic changes ,and (MDR) to the anti-TB
drugs as a result of inadequately supported and /
or disorganized treatment services.
In 1993, the World Health Organization
declared a state of global emergency for TB due
to the steady worldwide increase in the disease.
Along with HIV and malaria, TB has been declared
a global enemy.
An effective TB control program requires early
diagnosis and immediate initiation of treatment.
Background
Delay in diagnosis is significant with regard to not
only disease prognosis at the individual level but
also transmission within the community and the
reproductive rate of the TB epidemic.
The goal of TB control programs is to arrest
transmission within the community. Achieving
this goal takes considerable time, because most
individuals in endemic areas are already infected,
constituting a reservoir that continuously
contributes to the pool of infectious cases.
Background
WHO Global Tuberculosis Program had developed
a new strategy to meet the needs of global
tuberculosis control “DOTS” (Directly Observed
Treatment Short course).
DOTS strategy with its five components (Political
commitment, Good quality diagnosis, Good quality drugs, Shortcourse chemotherapy, and Systematic monitoring and
accountability) is a patient friendly strategy
implemented by patient oriented supervisors.
DOTS is currently the standard approach to care.
Though expensive, it is probably less costly than
admission and high cure rates have been achieved.
Descriptive Epidemiology
• More common in developing countries.
• Poverty
- Crowding living conditions
- Reduce access to health care
• Race/ethnicity
• Migration
• Population density (rural vs. urban)
• Substance abuse/alcoholism
• Nutritional status
Descriptive Epidemiology
• In developed countries is more frequent among
immigrants, drug users, HIV, homeless, and those
living in inner cities.
• HIV alone does not explain the increase of TB.
• Higher among males than females.
• The leading cause of death among women due to
infectious diseases worldwide.
• The main cause of deaths occurred among young
people and adults due to infectious diseases.
Descriptive Epidemiology
• Responsible for the highest number of orphans at
the global level compared to other infectious
diseases.
• In developed countries more frequent in old age
(shift in age).
• Age-specific incidence varies over countries and
socioeconomic conditions:
– Elders in Developed countries
– Young adults in developing countries*
* Mainly those in their most productive years of life
Epidemiological Statistics
• Overall, 1/3 of the world population is currently
infected with M. tuberculosis.
• 16 million TB infected (including TB/HIV).
• 1% of the world's population are infected with
tuberculosis every year.
• every second , one person in the world get
infection with TB.
• 5 – 10% of persons exposed to TB infection
progress to TB diseased.
• 12 million new cases, 80% in 22 high-burden
countries.
Epidemiological Statistics
• 2 million deaths.
• Over 1/4 million deaths due to TB/HIV.
• TB is the main cause of deaths occurred among
HIV/AIDS patients, where it accounts about 15%
of all deaths.
• More than 100,000 children die from TB each
year.
• 95 % of all TB cases and 98 % of TB deaths occur
in developing countries.
Epidemiological Statistics
• 75 % of TB cases in developing countries are in
the economically productive age (15-50 years).
• 3.2% of all TB cases nationwide occurred among
residents of correctional facilities.
• Multi-drug resistance (MDRTB) present in 102 of
109 countries surveyed from 1994-2003.
• If TB is left unchecked in the next 20 years,
almost one billion people will become newly
infected, 200 million will develop the disease,
and 35 million will die of it.
Epidemiological Statistics
• In Kuwait, tuberculosis is an important public
health concern.
• In year 2010, 957 persons ( both Kuwaiti and non
Kuwaiti ) were diagnosed as TB cases (all forms).
• 358 cases of them were infectious ( smear
positive ).
• Incidence rate of TB cases (all forms) was about
26.8, and of smear positive cases was 10.8 (4.6
for Kuwaiti and 13.6 for non Kuwaiti).
Epidemiological Statistics
TB case notifications in Kuwait (2001-2010)
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
Smear positive
174
206
201
247
187
284
294
345
386
387
Smear negative
72
91
73
65
95
76
94
158
155
163
Extra-pulmonary
250
283
288
242
234
284
277
363
391
407
Total New Cases
496
580
562
554
516
644
645
866
932
957
Epidemiological Statistics
Incidence rate of TB cases (all forms) in Kuwait
(2001-2010)
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
21.8
25.6
24.3
23.3
21.0
21.1
21.2
25.2
27.1
26.8
(IR per 100 000)
Incidence rate Of TB cases (all forms) in Kuwait (2001-2010)
30
(IR per 100 000)
25
20
15
10
5
0
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
Epidemiological Statistics
Incidence rate Of smear positive pulmonary TB in Kuwait
(2001-2010)
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2.8
4.2
3.7
4.3
2.5
3.6
3.3
4.2
3.8
4.6
Non Kuwaiti
10.8
12.2
11.8
14.2
10.9
12.1
11.8
12.7
14.7
13.6
Total
7.6
9.1
8.6
10.3
7.6
9.3
9.0
10.0
11.2
10.8
Kuwaiti
(IR per 100 000)
Incidence rate Of smear positive pulmonary TB in Kuwait
(2001-2010)
16
14
(IR per 100 000)
12
10
8
6
4
2
0
2001
2002
2003
Kuwaiti
2004
2005
Non Kuwaiti
2006
2007
Total
2008
2009
2010
The increasing TB incidence rate in Kuwait can be
attributed to:
• Increased number of expatriates seeking residency
in Kuwait from south-east Asia (40-50% of
worldwide TB cases).
• Sustained efforts in the area of screening and early
case detection of TB cases.
Levels of Prevention and Their Goals
Prevention efforts focus on the following three
goals:
• Primary prevention – preventing TB infection
• Secondary prevention – preventing TB disease
• Tertiary prevention – preventing TB morbidity
and mortality
Prevention
• Designing and implementation of health education
programs for all community sectors to educate the
public in mode of transmission and methods of
control and regarding the importance of early
diagnosis and continued adherence to treatment.
• Reduce or eliminate those social conditions that
increase the risk of infection.
• Set up TB prevention and control programs in
institutional settings, closed communities and
minorities.
Prevention
Screening
• Early identification through efficient screening
programs and successful treatment of persons
with TB disease is the most effective means of
preventing disease transmission.
• Screening programs can also detect persons with
LTBI who are at high risk for progressing to TB
disease.
Prevention
Screening
Infectious or potentially infectious ???
• Infectious TB: all cases of respiratory (pulmonary or
laryngeal) TB which are sputum smear-positive and
culture-positive (if culture is available).
• Potentially infectious TB: all cases of respiratory
(pulmonary or laryngeal) TB which are sputum smearnegative and culture-positive (susceptible, MDR-TB or
XDR-TB).
• Non-infectious TB: all cases of respiratory TB which have
two consecutive negative sputum-smear and negative
culture (if culture is available) results.
Prevention
Screening
In Kuwait,
• TB screening is enhanced in last years particularly
among expatriates with applying strict measures for
early case detection, diagnosis and management.
• Active Surveillance for TB cases.
• Enhancing effective collaboration between TB and
HIV/AIDS prevention and control programs.
• Monitoring national tuberculosis programs to prevent
the emergence of (MDR) & (XDR-TB)
Prevention
• Management of close contacts of open TB cases.
• Preventive chemotherapy (isoniazid for 6-12
months) has been effective in preventing the
progression of LTBI to TB disease.
• Eliminate bovine TB among diary cattle, pasteurize
or boil milk.
• Applying measures to prevent silicosis among
those working in industrial plants and mines.
Prevention
Vaccination, BCG (Bacille Calmette-Guerin)
• BCG vaccine is the most vaccine in use
worldwide. It has been used for the first time to
protect against human tuberculosis in 1921, and
since this date until today, the BCG is the only
vaccine for prevention of TB.
• WHO estimated that more than one billion
people worldwide have been vaccinated with
BCG.
• BCG vaccines is safe, where no mention of having
caused a serious problem since the beginning of
its use until now.
Prevention
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Vaccination, BCG (Bacille Calmette-Guerin)
BCG vaccine is live attenuated vaccine, which is
derived from the bovine strain of tuberculosis
bacteria (mycobacterium bovis).
BCG gives immunity to some extent against
tuberculosis and its influence extends for years.
IT reduces the risk of progression TB infection to
serious forms of tuberculosis such as TB
meningitis and miliary TB.
TST is not contraindicated for persons vaccinated
with BCG.
Prevention
Vaccination, Bacille Calmette-Guerin (BCG)
• Cannot distinguish between TST reactions caused
by BCG and those caused by natural mycobacterial
infection, but ≥ 20-mm indurations is usually NOT
caused by BCG
In Kuwait,
• Since 1/1/2005, all children in Kuwait must be
vaccinated by BCG by the end of third month of
life. BCG vaccination coverage had reached about
99%.
Prevention
WHO guidelines for air travel
• People with infectious or potentially infectious TB
should postpone all travel by commercial air
transportation of any flight duration until they
become non infectious.
• Those people must be received 2 weeks of
adequate treatment, and they must be sputum
smear negative on at least two occasions (2
consecutive negative sputum-culture results – if
MDR or XDR).
Prevention
WHO guidelines for air travel
• The public health authority must be Informed
when an infectious or potentially infectious TB
patient has a history of commercial air travel
within the previous 3 months.
• The concerned airline must be Informed of
infectious and potentially infectious passengers
travelling against medical advice and request that
boarding be denied.
Prevention
WHO guidelines for air travel
• If patient has exceptional circumstances, it must be
ensure that the airline(s) and all involved
authorities have agreed the procedures for travel.
• The public health authority must be informed of all
exceptional circumstances.
Prevention
• DOTS (and DOTS- plus) is currently the standard
approach to care,
- Achieve high cure rates of up to 95%,
- Low cost compared to other methods of treatment,
- Prevents the emergence of new cases of TB,
- Prevents the emergence of drug-resistant TB
through a commitment to full and complete
treatment until complete cure.
• In Kuwait, the National tuberculosis Program (NTP) has
adopted DOTS strategy since 1998, and expanded it
rapidly and achieved high population coverage.
Prospective achievements
• Developing sufficient, sustainable, human and
financial resources to meet the challenge of
stopping tuberculosis.
• Comprehensiveness of services for management
of high-risk groups.
• A high quality of DOTS activities, using existing
mechanisms and new initiatives.
Prospective achievements
• Implementing the Practical Approach to Lung
Health (PAL), and assessing its potential impact
on TB case detection and on the rationalization of
drug prescriptions.
• Involvement of drug resistance surveillance.
• DST (Drug Sensitivity Testing) & Molecular
epidemiology in the form of PCR and DNA finger
printing.
• Restrictions and legislations to control TB drugs in
private sectors.