Part 2 Ch1

• clinical microbiology • applied microbiology (recombinant DNA technology) • food microbiology (yeasts) • environmental microbiology (microorganisms in the soil)

• the study of causative agents of human infectious diseases and their reactions • related to pathogenesis, diagnosis, treatment and control of infection (+basic characteristics features) • bacteria (bacteriology), virus (virology), fungi (mycology) and parasites (parasitology)

• to understand how microorganisms interact with individuals and population • to understand how microorganisms cause diseases • to understand how diseases can be prevented and controlled • to understand the role of nurses in control and prevention of infection

• microbial diseases • basic characteristics of microorganisms • microbial pathogenesis • diagnosis of infectious disease • treatment of infection • prevention of infection

• classification of microorganisms in the human body and the environment • characteristics feature of microorganisms (bacteria, virus, protists and fungi) • identification of normal microbiota and pathogens

• source of infections (how microorganisms enter a host and cause disease) • route of transmission (how infection is transmitted in hospitals, communities and populations) • etiology (cause), pathogenesis (development) and epidemiology (frequency and distribution) of infections of different body systems

• collection and transport of specimens • identification of pathogens from collected specimens: bacterial culture and biochemical tests

• use of antimicrobial treatments: antibiotics and vaccines • importance of aseptic techniques in patient management (sterilisation and disinfection) • control the spread of infection in hospitals and communities: hand hygiene and personal protective equipments (PPE)

• organisms that can only be seen under microscope • named by binomial nomenclature: genus name (starts with capital letters) and specific name (small letters) • both names should be italicised or underlined • scientific names can be abbreviated

• use visible light to resolve objects –> visible light passes directly through the lenses and specimen • total magnification = eyepiece magnification x objective magnification • in a compound microscope, the image from the objective lens is magnified again by the eyepiece

• above 0.2mm (200um); above 200nm (0.2um); under 200nm (0.2um) • fungi (above 200um) • protozoa (between 20um and 200um) • bacteria (between 0.2um and 20um) • viruses (between 2nm and 0.2um=200nm)

• light microscope => observe the morphology of microorganisms such as bacteria, fungi, protozoa and algae under living (unstained) or non-living (stained) state => cannot observe microbes less than 0.2um (200nm) => resolving power: 0.2um • TEM (transmission electron microscope) => examine cellular and viral internal structures => gives 2D images only => specimen is non-living => resolving power: 0.2nm • SEM (scanning electron microscope) => examine surface features of cells and viruses => gives 3D images => specimen is non-living => resolving power: 20nm

• microbes –> cellular microbes; acellular microbes • cellular microbes –> prokaryotes; eukaryotes • acellular microbes –> viruses • prokaryotes –> bacteria • eukaryotes –> fungi and protist (protozoa and algae)

• prokaryotes vs eukaryotes => no true nucleus; have true nucleus => no membrane-bound organelles (eg. mitochondria and chloroplast; have membrane-bound organelles => simpler and smaller; more complex => reproduced by binary fission; reproduced by mitosis and meiosis

• bacteria (prokaryotes, unicellular) • virus (acellular) • fungi (eukaryotes, unicellular or multi-cellular) • protists (eukaryotes, unicellular or multi-cellular)

• in the environment and human body

• sites where no microorganisms should be found in the human body • brain and spinal cord (CNS) • blood (circulatory system) • kidneys (urinary system) • lungs (respiratory system) • ovaries and testes (reproductive system)

• normal microbiota (normal flora) => non-pathogenic that live symbiotically in the human body => does not cause disease => usually beneficial to humans => very abundant as there are 10^13 body cells which there are 10^14 normal flora => eg. lactobacilli • pathogens => have the ability to cause disease in health individuals • opportunistic pathogens => do not cause disease under normal conditions, they wait for opportunities to cause disease (only cause disease in people with immunodeficiency) => eg. e coli, staphylococcus

• mutualism (both benefit) (eg. E. coli) • commensalism (one benefit one unaffected) (eg. Staphylococcus) • parasitism (one benefit and one harmed) (eg. H1N1)

• human => bacteria synthesise vitamins (vitamin B and K) => bacteria produce digestive enzymes to break down food (eg. polysaccharides in plant cell wall ) => protect host by preventing pathogenic organisms from growing • bacteria => provide place for them to survive and multiply => obtain food source

• infect and colonise internal or external body surface –> inflammation and tissue damage • produce toxin –> ingestion of toxin –> disease (food poisoning)