TUBERCULOSIS-epidemiology-risk-factor.ppt

TB

1. TUBERCULOSISTUBERCULOSIS
OVERVIEW OF EPIDEMIOLOGY, RISK OVERVIEW OF EPIDEMIOLOGY, RISK
FACTORS MANAGEMENT & CONTROLFACTORS MANAGEMENT & CONTROL
DR. OKWUDIAFORDR. OKWUDIAFOR
FEDERAL MEDICAL CENTREFEDERAL MEDICAL CENTRE
YABAYABA

2. OVERVIEW OF EPIDEMIOLOGYOVERVIEW OF EPIDEMIOLOGY

3. IntroductionIntroduction
Tuberculosis is a chronic granulomatous Tuberculosis is a chronic granulomatous
disease caused by mycobacterium disease caused by mycobacterium
tuberculosis. It is spread principally by tuberculosis. It is spread principally by
inhalation of infected droplets. inhalation of infected droplets.
Transmission is determined by Transmission is determined by
(1) number of viable bacilli in the droplets(1) number of viable bacilli in the droplets
(2) the aerosolization of droplet nuclei by (2) the aerosolization of droplet nuclei by
coughing talking etccoughing talking etc
(3) Susceptibility of the host (3) Susceptibility of the host
(4) Length of time of exposure to (4) Length of time of exposure to
contaminated air.contaminated air.

4. EpidemiologyEpidemiology
Tuberculosis is the leading cause of Tuberculosis is the leading cause of
death from a curable infectious death from a curable infectious
disease in the world.disease in the world.
It is present in one third of the It is present in one third of the
world’s population.world’s population.
It is estimated that nine million new It is estimated that nine million new
cases occur annually and approx cases occur annually and approx
three million deaths annually from three million deaths annually from
this disease around the world.this disease around the world.

5. The Sub Saharan African region has The Sub Saharan African region has
the highest incidence rate of over the highest incidence rate of over
300 cases per 100,000 populations 300 cases per 100,000 populations
per year.per year.
However the majority of patients are However the majority of patients are
in the worlds most populous in the worlds most populous
countries of Asia Bangladesh China countries of Asia Bangladesh China
India Indonesia and Pakistan.India Indonesia and Pakistan.

6. Tuberculosis is a disease of men and Tuberculosis is a disease of men and
young adults. The difference in sexes young adults. The difference in sexes
is as a result of exposure to infection is as a result of exposure to infection
and in susceptibility to development and in susceptibility to development
of disease.of disease.

7. HISTORYHISTORY
Tuberculosis was on the decline in Tuberculosis was on the decline in
Western Europe and North America Western Europe and North America
beginning in the mid 19th century This beginning in the mid 19th century This
was further. accelerated by the was further. accelerated by the
development of an effective chemotherapy development of an effective chemotherapy
in the second half of the 20th century.in the second half of the 20th century.
From 1985 there has been an increase in From 1985 there has been an increase in
global tuberculosis incidence global tuberculosis incidence
–Attributable to the spread of HIV in worldwide Attributable to the spread of HIV in worldwide
especially in Africa.especially in Africa.

8. Globally 13% of adults with newly Globally 13% of adults with newly
diagnosed tuberculosis were infected diagnosed tuberculosis were infected
with HIV.with HIV.
In Africa the rates are over In Africa the rates are over
34%’Where HIV rates are high such 34%’Where HIV rates are high such
as in Botswana South Africa Zambia as in Botswana South Africa Zambia
Zimbabwe in 2004 rates of co Zimbabwe in 2004 rates of co
infection exceed 50%.infection exceed 50%.

9. In USAIn USA
–The increase also occurred as a result of The increase also occurred as a result of
large population of large population of
–Homeless personsHomeless persons
–Immigrant populationImmigrant population
–IV drug abusersIV drug abusers
–Pts on chemotherapy and transplant pts.Pts on chemotherapy and transplant pts.
–Prison inmatesPrison inmates
–Health care workersHealth care workers

10. IN USA The trend has been reversed from IN USA The trend has been reversed from
1992 through 2001 the incidence of TB 1992 through 2001 the incidence of TB
decreased by 40%. In 2001 the TB decreased by 40%. In 2001 the TB
incidence rate was 5.6 per 100,000 incidence rate was 5.6 per 100,000
persons.persons.
This fall was attributed to effective TB This fall was attributed to effective TB
control programmes with prompt control programmes with prompt
identification of cases prompt initiation of identification of cases prompt initiation of
effective therapy and efforts to ensure effective therapy and efforts to ensure
compliance with treatment. compliance with treatment.

11. The incidence rate in Sub Saharan is The incidence rate in Sub Saharan is
still on the increase. still on the increase.
In fact the continued global increase In fact the continued global increase
in Tuberculosis is attributable to in Tuberculosis is attributable to
continued rise in Africa.continued rise in Africa.
–attributable to HIV spread in Africa.attributable to HIV spread in Africa.

15. In eastern Europe there was a In eastern Europe there was a
resurgence of the disease in the resurgence of the disease in the
1990s due to mainly down turn in 1990s due to mainly down turn in
economy poor health services poor economy poor health services poor
TB control. Also this led to TB control. Also this led to
emergence of MDR-TB. There is now emergence of MDR-TB. There is now
however a slowing down of rate of however a slowing down of rate of
increase and the incidence might increase and the incidence might
now be in decline.now be in decline.

16. SummarySummary
HIV infection has clearly had a profound HIV infection has clearly had a profound
effect on tuberculosis epidemiology but effect on tuberculosis epidemiology but
in addition other potentially important in addition other potentially important
risk factors include risk factors include
–chronic diseases, diabetes under nutrition chronic diseases, diabetes under nutrition
smoking air pollution social deprivation. smoking air pollution social deprivation.
Patients on immunosuppressive medication Patients on immunosuppressive medication
Transplant patients and Cancer Transplant patients and Cancer
Patients.Patients.
Inadequate health services Inadequate health services

17. RISK FACTORS MANAGEMENT RISK FACTORS MANAGEMENT
AND CONTROL OF AND CONTROL OF
TUBERCULOSISTUBERCULOSIS

18. Tuberculosis remains the leading Tuberculosis remains the leading
cause of death despite efforts of the cause of death despite efforts of the
world Health Organization world Health Organization
International Union against International Union against
Tuberculosis and Lung disease and Tuberculosis and Lung disease and
CDC.CDC.

19. The UN Millennium development Goal The UN Millennium development Goal
(MDG) is to have halted by 2015 and (MDG) is to have halted by 2015 and
begun to reverse incidence of Malaria begun to reverse incidence of Malaria
and other diseases including and other diseases including
tuberculosis.tuberculosis.
The Stop TB Partnership aims to The Stop TB Partnership aims to
halve prevalence and death rates halve prevalence and death rates
globally between 1990 and 2015.globally between 1990 and 2015.

20. Preventive StrategiesPreventive Strategies
Important in the effort to control and Important in the effort to control and
eliminate TB world wide.eliminate TB world wide.
These includeThese include
– prophylaxis for infected patients, prophylaxis for infected patients,
–case finding and infection control case finding and infection control
– vaccination strategies.vaccination strategies.

21. Control StrategiesControl Strategies
High Risk Groups should be identified. High Risk Groups should be identified.
–1. Persons known or suspected to have HIV 1. Persons known or suspected to have HIV
infection.infection.
–2. Close contacts of patients with active TB2. Close contacts of patients with active TB
–3. Immunosuppressed patients e.g. transplant3. Immunosuppressed patients e.g. transplant
–4. Patients with serious medical conditions such 4. Patients with serious medical conditions such
as cancer diabetes end stage renal disease as cancer diabetes end stage renal disease
gastrectomy gastrectomy
–5. Residents and staff of long term facilities e.g. 5. Residents and staff of long term facilities e.g.
prisons nursing homes etcprisons nursing homes etc

22. These individuals should undergo These individuals should undergo
screening tests for latent TB with screening tests for latent TB with
Tuberculin skin test. Tests could be Tuberculin skin test. Tests could be
done periodically and when they are done periodically and when they are
positive they are screened for active positive they are screened for active
disease through history physical exam disease through history physical exam
CXR.CXR.
They should also be offered They should also be offered
prophylaxis when positive.prophylaxis when positive.

23. PROPHYLAXISPROPHYLAXIS
Involves the use of INH as first line Involves the use of INH as first line
duration should be 6 to 9 months.duration should be 6 to 9 months.
Rifampicin has been used to 4to 9 Rifampicin has been used to 4to 9
months.months.
Combination of rifampicin and Combination of rifampicin and
pyrazinamide for 2 monthspyrazinamide for 2 months
Complications neuropathy, hepatitisComplications neuropathy, hepatitis

24. VACCINE STRATEGIESVACCINE STRATEGIES
BCGBCG
–Confers 60% to 65% protectionConfers 60% to 65% protection
–Disemminated diseaseDisemminated disease
–Tuberculous menigitisTuberculous menigitis
–DeathDeath
ImmunityImmunity
–Wanes Wanes
Time of Vaccination differsTime of Vaccination differs

25. DisadvantagesDisadvantages
–Interference with Tuberculin testingInterference with Tuberculin testing
Newer Vaccines Newer Vaccines

26. Case Finding and treatmentCase Finding and treatment
Rapid Rapid detection of TB in patients is detection of TB in patients is
important. Appropriate treatment is important. Appropriate treatment is
applied this will reduce the rate of applied this will reduce the rate of
transmission.transmission.
Do contact tracing. Do contact tracing.
–Screening involves all close family Screening involves all close family
members and other occupants of the members and other occupants of the
household.household.
–Contacts at school and work. Contacts at school and work.

27. Effective control programEffective control program
Better diagnostic toolsBetter diagnostic tools
Better medicationBetter medication
Directly observed therapyDirectly observed therapy
–Implemented in 182 countries covering 77% Implemented in 182 countries covering 77%
–Reductions in China India Tanzania Uganda Reductions in China India Tanzania Uganda
MalawiMalawi
–Failure in Africa where rise continuesFailure in Africa where rise continues

28. DOTS strategyDOTS strategy
Long term planning and adequate Long term planning and adequate
human and financial recourses human and financial recourses
Case detection by sputum smear Case detection by sputum smear
microscopymicroscopy
Standard short term Rx given under Standard short term Rx given under
direct observationdirect observation
Adequate uninterrupted drug supplyAdequate uninterrupted drug supply
Systematic monitoring and Systematic monitoring and
accountability for every patient accountability for every patient
diagnosed.diagnosed.

29. STOP TB STRATEGYSTOP TB STRATEGY
VisionVision
–World free of TBWorld free of TB
GoalGoal
–Reduce Global burden of TB by 2015Reduce Global burden of TB by 2015
ObjectivesObjectives
–Achieve universal access to high quality Achieve universal access to high quality
diagnosis and Rxdiagnosis and Rx
–Reduce human sufferingReduce human suffering
–Protect poor and vulnerable populations from Protect poor and vulnerable populations from
TB TB/HIV MDR-TBTB TB/HIV MDR-TB
–Support new tools.Support new tools.

30. DOTSDOTS
Directly observed therapy strategyDirectly observed therapy strategy