What type of disease is Tuberculosis?
- An INFECTIOUS disease-
- It can affect any part of the body, but is usually found in the lungs AS THESE ARE THE FIRST SITE OF INFECTION
How many people does TB kill every year?
2 million people
TB is caused by 1 of 2 rod-shaped BACTERIA, what are they called?
Mycobacterium Tuberculosis OR Mycobacterium Bovis <-- found in cattle
What are the symptoms of Pulmonary Tuberculosis?
- - Persistent cough
- - Tiredness (fatigue)
- - Shortness of breath
- - lack of appetite-which leads to weight loss
- - fever
- - When the disease develops-coughing up blood.
How is Pulmonary Tuberculosis spread?
- Through the air by droplets
- they are released into the air when the infected person coughs, sneezes, laughs or even talks.
Mycobacterium Tuberculosis is a RESISTANT bacterium, but how long can it survive?
As it takes frequent contact with a person with TB to contract the disease, which people are at most risk?
Family and close friends- not just people in the street.
Who else is at greater risk of getting TB?
People who are from countries where TB is common, and people with REDUCED IMMUNITY
Who are those with reduced immunity?
- The very young or very old
- Those with AIDSThose with OTHER medical conditionsThe malnourishedThe homelessAlcoholics and injected-drug users
- In these case, TB is an OPPORTUNISTIC DISEASE
Once the Mycobacterium tuberculosis has been inhaled by someone not immune to it it takes this course....The bacteria grow and divide in the UPPER regions of the lungs...WHY?
There is a plentiful supply of OXYGEN in the upper regions of the lungs.
When the body's immune system responds to the TB bacterium, what do the WHITE BLOOD CELLS do??
They accumulate at the site of infection as INGEST the Mycobacterium Tuberculosis
As a result of the immune response, what happens to the lymph nodes?
They ENLARGE and get INFLAMED.
What does this inflammation and enlargement of the lymph nodes lead to?
It drains that area of the lungs.
What is this called (the drainage of that area of the lungs due to the enlargement and inflammation of the lymph nodes)?
The primary infection-and. it usually occurs in kids
In HEALTHY people, how long does it take for the infection to be CONTROLLED?
- a FEW WEEKS.
- BUT...some bacteria usually remain.
What is POST-PRIMARY tuberculosis?
When the bacteria RE-EMERGES many years later and causes a SECOND INFECTION of TB. (usually occurs in adults)
What is the course of infection for post-primary TB?
Its also arises in the upper regions of the lungs, HOWEVER, it is not so easily controlled because the bacteria DESTROY THE TISSUE OF THE LUNGS
What is the result of the lung tissue being destroyed?
It results in CAVITIES, and where the lungs repair itself, SCAR TISSUE
What could happen if the TB doesn't get treated?
It could spread to the rest of the body and can be FATAL.
What is the MAIN biological PREVENTATIVE measure against TB?
Vaccination- children in the UK are routinely tested for their immunity to TB.
Giving Vaccination to people who are ALREADY IMMUNE to TB is dangerous and uneccessary.
What are those people who are NOT immune to TB given in their vaccine?
A weakened strain of MYCOBACTERIUM BOVIS
Why a weakened strain of Mycobacterium Bovis?
Weakening the bacteria means that it is LESS LIKELY to cause the SYMPTOMS of TB
There are social and economic measures that can be introduced to REDUCE THE NO' OF TB CASES...what are they?
- Better education about TB -especially the importance of completing the whole drug course.
- MORE and BETTER housing
- better HEALTH facilities and TREATMENT.
- better nutrition (so that peoples immune systems don't weaken as a result of poor nutrition)
What is another means of controlling TB?
What is often the problem with drug treatment?
- They have to be taken for a long period (6-9 months)
- also, the development of strains of M. Tuberculosis that no longer respond to drugs.
Despite all these measures, there has been a RECENT INCREASE in the no' of cases of TB in many developing countries, why?
- Because .....
- spread of HIV
- strains of M. Tuberculosis that don't respond to drugs
- no' of people living rough
- larger proportion of elderly people in the population