1. Unit 21 Biomedical Science Techniques

2. Topic we will cover  Organisms that have medical importance  How the body defends itself  Blood transfusions & its science  Cell pathology as a diagnostic tool  Biochemistry of the body

3. Infection  What is an infection?  Where does it come from?  How can it be transferred?  How does it enter our bodies?  How can we prevent infection?

4. Routes of Infections

5. Contact  Has to be close  Can be sexual or non sexual  Can be direct or indirect  Examples are Influenza, Colds, Tuberculosis, HIV, STD’s

6. Vehicle  Non-living  Contaminated by infectious agent  Examples are air, water, Blood  Legionaires, Tuberculosis in Milk

7. Vector  Usually an arthropod  Usually carrying the infectious agent rather than being the infectious agent  Examples are Flies, Fleas, Ticks & Lice  Cause Typhoid, Cholera, The Plague, Malaria

8. Routes into the body

9. Orifices  Essentially a break in the skins surface  Include Eyes, nose, ears, mouth, anus & urethra  Special adaptations to prevent entry (looked at later on in course)

10. Droplets  Minute droplets of liquids that can be either inhaled or ingested  Normally come from other people sneezing or coughing  Sometimes known as aerosols

11. Body Fluids  Fluids either in, made by or secreted by the body  Examples are Saliva, blood, CSF, sweat, Semen & vaginal secretions

12. Cuts  Basically a breach of the skins natural defences  Cause by lots of different things  Allows entry of micro-organisms into the body

13. Sources of Infection

14. Human Reservoirs  Sometimes known as an infected host  Carries the infectious agent but may not exhibit symptoms of the infection  Can carry the infection for long periods of time  Difficult to identify  Examples are HIV, Tuberculosis, Typhoid

15. Animal Reservoirs  Non-human source of infection  Can cause infection in Humans (Zoonosis)  Examples are Rabies, Anthrax, Lymes Disease & the Plague

16. Non-living reservoirs  Store of the infectious material  Strictly a vehicle but could include contaminated water, untreated waste, decayed food etc.

17. Prevention

18. Sterilisation  Removal and destruction of micro- organisms  Can be achieved through heat, washing, irradiation  Basic processes such as washing hands can improve cleanliness

19. Antibiotics  Can be used both internally and externally  Interrupt the bacterial reproduction process  Effective against a wide range of bacteria  Bacteria can develop resistance

20. Antivirals  Developed recently  Mainly external but some available internally now.  Being used in the fight against HIV and AIDS

21. Antifungals  Used to treat fungal infections  Examples are athletes foot, thrush, ringworm