Why was there a decline in TB incidence pre 1980s?
There was advancements in housing, better diets and hygiene.
Where in the UK is TB a major problem?
- London
What bacteria is responsible for TB?
Mycobacteria
Where do mycobacterium live?
In soil and water
What species of mycobacterium are responsible for TB?
- Mycobacterium bovis
What species of mycobacterium is responsible for leprosy?
Mycobacterium leprae
What other species of mycobacterium are there?
What kind of disease is TB?
Very slow grow growing, progressive disease that requires long treatment
What kind of bacteria is mycobacterium?
- Aerobic
Where does mycobacterium have a predilection for?
Apices of the lungs
Describe the structure of mycobacteria.
- Contains lipids, peptidoglycans and arabinomannans
What is mycobacteria resistant to?
- Neutrophil and macrophage destruction
What test is used to identify mycobacteria?
Acid and alcohol fast bacilli using a ZN stain
What is the source of transmission of mycobacteria?
How are outdoor mycobacteria eliminated?
By UV radiation and infinite dilution
What happens when mycobacteria droplets are inhaled?
How is TB contracted through mycobacterium bovis?
- Deposited in cervical and intestinal lymph nodes
How do activated macrophages cause necrosis?
What mediates the immunological response?
Th1 cells
What does the Th1 mediated immunological response lead to?
- Tissue destruction as a consequence of activation of macrophages
What factors affect susceptibility?
What affects outcome of infection?
- Number of organisms
How might a resistant host become a susceptible host?
With age
How might a susceptible host become a resistant host?
With a better diet