1. Introduction to Microbiology & Parasitology lecture

Brief introduction of concepts in Medical microbiology and parasitology.

1. MICROBIOLOGY & PARASITOLOGY By Mr. Vincent Ejakait

2. CONTENT Definition of terms Historical development of microbiology Ecological relationship Factors promoting growth & development of microorganisms Importance of microorganisms Classification of microorganisms Mr. Vincent Ejakait 2

3. Definitions Mr. Vincent Ejakait 3

4. DEFINITIONS MICROBIOLOGY: Is the study of microscopic organisms, such as bacteria, viruses, fungi and protozoa.  Mr. Vincent Ejakait 4

5. PARASITOLOGY: Is the study of parasites, their hosts, and the relationship between them. Mr. Vincent Ejakait 5

6. IMMUNOLOGY: Is the study of the immune system, which protects us from infection Mr. Vincent Ejakait 6

7. History People attributed diseases to witchcraft and the devil. Later they believed disease was caused by miasma (an unpleasant or unhealthy smell) 1632-1723 Antoni van Leeuwenhoek: was the first to demonstrate the presence of micro-organisms via a microscope Louis Pasteur: showed that there were germs present in the environment Louis Pasteur: opened the field of sterilization He also developed vaccines (anthrax vaccine) Mr. Vincent Ejakait 7

8. History cont.. Robert Koch’s contribution: Described methods of preparing cultures Discovered the causative agents of: Tuberculosis Cholera Fleming and Chain developed penicillin in 1929 from a fungus called Penicillium Mr. Vincent Ejakait 8

9. History cont.. For more of the history, check the class email for the handout on History of microbiology and immunology Mr. Vincent Ejakait 9

10. Ecological Characteristics Host: Is an organism that harbors a guest organism Parasites: Is an organism that lives within or on a host Pathogens: Is a biological agent that causes disease or illness to its host. Mr. Vincent Ejakait 10

11. Ecological relationships The interaction among organisms within or between overlapping niches can be characterized into 5 types of relationships: Competition Predation Commensalism Mutualism Parasitism Symbiosis Mr. Vincent Ejakait 11

12. 1. Competition Competition is when individuals or populations compete for the same resource An example is lions and hyenas that compete for prey. Mr. Vincent Ejakait 12

13. 2. Predation Predation is when one organism eats another organism to obtain nutrients. The organism that is eaten is called the prey. Examples are owls that eat mice, and lions that eat gazelles. Mr. Vincent Ejakait 13

14. 3. Commensalism Commensalism is a relationship in which one organism benefits while the other is neither helped nor harmed. Mr. Vincent Ejakait 14

15. 4. Parasitism Parasitism is a relationship in which one organism benefits and the other organism is harmed, but not always killed. The organism that benefits is called the parasite, The one that is harmed is the host. Example such as intestinal worms that live inside the host Mr. Vincent Ejakait 15

16. 5. Mutualism Mutualism is a relationship in which both species benefit. Mr. Vincent Ejakait 16

17. Summary of symbiosis Mr. Vincent Ejakait 17

18. Factors promoting growth and development of micro-organisms Nutrients: All microorganisms need food Temperature: Very high and very low temperatures discourage growth pH Levels : most organisms prefer neutral pH Moisture : All microorganisms require some level of water Oxygen requirement : Some organisms are anaerobes and aerobes Mr. Vincent Ejakait 18

19. Importance of Micro-organisms For vaccine production e.g polio vaccine from the virus For production of food: yeast used to make bread, bacteria important for making yoghurt. Soil microbes help to recycle nutrients: Used in the brewing of alcohol Fungi help in the degradation of living things that have died Mr. Vincent Ejakait 19

20. Classification of micro-organisms Bacteria Fungi Virus Protozoa Mr. Vincent Ejakait 20