Download Tuberculosis

TUBERCULOSIS
Paige Derouin
History
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Began infecting the first human ancestors as long as
500,000 years ago
In 1882 – claimed the lives of 1 in 7 people
• Ran rampant in crowded European and American cities
• March 24 – Robert Koch discovers Mycobacterium tuberculosis
• Koch’s discovery allowed scientists to begin working on a
treatment and vaccine for TB.
1908 - Albert Calmette and Camille Guérin: BCG vaccine
o First used in 1921 preventatively
History Cont’d
• 1943 - microbiologist Selman Waksman discovered
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streptomycin
1970s – Most people believe TB is completely
irradiated
1998 – genetic sequencing of Mycobacterium
tuberculosis
2006 – first case of extensively drug resistant TB in
South Africa
2008 – 49 countries reported cases of extensively
drug resistant TB
Incidence
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In 2008 highest incidence was in Southeast Asia
98% of TB related deaths occur in developing
countries
In the US, there were 4.2 cases per 100,000
people in 2008
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Most of the US cases occurred in Florida, Texas,
California, and New York
World Incidence 2006
World map showing reported cases of tuberculosis per 100,000 citizens. Red = >300,
orange = 200-300; yellow = 100-200; green 50-100; blue = <50 and grey = n/a.
Mycobacterium tuberculosis
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Rod shaped, gram
positive bacterium
Infection begins with
phagocytosis into a
macrophage
can remain inside the
host in a dormant form
and reactivate later
Diagnosis
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Diagnosis is based on:
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Symptoms

Producing cough, chest pain, night sweats, fatigue, fever
Medical history
 TB tests
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Tuberculin Skin Test
 Blood Tests
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Chest X-Rays
 Diagnostic microbiology
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Sputum smear – acid-fast bacilli
TB Tests

Tuberculin Skin Test
Injection of fluid into the skin of the lower arm
 48-72 hours later – checked for a reaction
 Diagnosis is based on height of the skin
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Blood Test
Newer test
 Based white blood cells’ response to the test
 Results available in 24 hours
 http://www.youtube.com/watch?v=s3v8M2Q6AGI&feature
=channel

Treatment
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Latent TB
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Not symptomatic or contagious
Usually treated with Isoniazid for 9 months
Confirmed with a chest X-Ray
Infectious TB
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Treatment is very expensive
Treated in phases - Isoniazid, Rifampicin, Pyrazinamide and
Ethambutol
1.
2.
Usually 3 drugs
2 different drugs
Treating Drug Sensitive TB
Treating Drug Resistant TB
Treating Extensively Drug Resistant TB
Problems with Treatment
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Very long treatment
Large number of drugs is expensive
Resistant Strains
3rd World countries
Steps to Prevention

WHO’s Stop TB Strategy
 DOTS
– reduce deaths from
TB by 50% by 2015,
eliminated by 2050
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March 24 – World TB Day
Research for a new vaccine
to replace or boost BCG
Works Cited
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“I am stopping TB” image. : http://www.tac.org.za/community/files/stop-
tb_medium.jpg
Treating extensively drug resistant TB:
http://www.niaid.nih.gov/topics/tuberculosis/Understanding/WhatIsTB/Sci
entificIllustrations/Pages/extensivelyDrugResistantIllustration.aspx
Treating drug resistant TB:
http://www.niaid.nih.gov/topics/tuberculosis/Understanding/WhatIsTB/Sci
entificIllustrations/Pages/multidrugResistantIllustration.aspx
Treating drug susceptible TB:
http://www.niaid.nih.gov/topics/tuberculosis/Understanding/WhatIsTB/ScientificIllu
strations/Pages/firstLineIllustration.aspx
Mycobacterium: http://www.students.stedwards.edu/aruiz5/interview.htm
World Incidence:
http://commons.wikimedia.org/wiki/File:Tuberculosis_reported_cases_2006.PNG