Higher Human Biology Unit 4 Immunology & Public Health KEY AREA 3:Transmission and Control of Infectious Diseases

Higher Human Biology We are going to build on the knowledge and skills that you developed during N5 and will learn about the following Immunology & Public Health key areas : - Key Area 1 – Non-specific Defences Key Area 2 – Specific Cellular Defences Key Area 3 – Transmission and Control of Infectious Diseases Key Area 4 – Active Immunisation and Vaccination and the Evasion of Specific Immune Responses by Pathogens

Physiology & Health Learning Intentions KEY AREA 3 – Transmission and Control of Infectious Diseases a)Infectious Diseases b)Epidemiological Studies of Infectious Diseases

3a) Infectious diseases caused by pathogens An infectious disease is one that is capable of being transmitted from one person to another by direct or indirect contact Infectious diseases are caused by many types of pathogens (e.g. viruses, bacteria, fungi, protozoa and multicellular parasites)

3b) Infectious diseases can be transmitted by  Direct physical contact (e.g. shaking hands)  Indirect physical contact (e.g. sharing contaminated cups, syringe needles)  Water (e.g. consuming contaminated water)  Food (e.g. consuming food contaminated from an infected person)  Body Fluids (e.g. saliva, seminal fluids)  Inhaled air (e.g. breathing in air infected by a person sneezing)  Vector Organisms (e.g. bitten by a mosquito infected with malaria)

3c) Infectious diseases can be controlled by:- Quarantine - compulsory isolation Antisepsis- complete sterilisation of equipment - applying antiseptics to wounds - using sterile gloves and surgical masks Individual Responsibility- good hygiene (hand-washing, showering) - care in sexual health (use condoms) - appropriate storage/handling of food (clean hands, storing uncooked meats away from cooked meats, sterilising knives) Community Responsibility- water quality supply (filtration, chlorination) - safe food webs (inspection, risk analysis and traceability of food sources) - appropriate waste disposal (refuse collected, recycles, incinerated or buried appropriately) Vector Control- use of insecticides and larvicides - sterilisation

3d) Epidemiological Studies of Infectious Diseases  Epidemiologists study the outbreak and pattern of infectious diseases to determine the factors which affect the spread of infectious disease  The Epidemiology of an infectious disease is the study of its characteristics such as:- -The location associated with its outbreak -Its pattern and speed of spread -Its geographical distribution

3e) Classification of the spread of infectious disease  Sporadic -occasional occurrence  Endemic -regular cases occurring in a particular area  Epidemic -unusually high number of cases in a particular area  Pandemic -a global epidemic – a series of epidemics that spreads across the world

3f) Control of Infectious Disease Measures Preventing Transmission Drug Therapy for those already infected Immunisation for those not yet infected Combination of the above

Immunology & Public Health Questions KEY AREA 3 – Transmission and Control of Infectious Diseases 1.Testing Your Knowledge 1Page 335 Q’s Quick Quiz