Chapter 7 - Disease Flashcards
Health
A state of complete physical, mental and social well being and not just the absence of disease
Infectious disease
Caused by a pathogen and can be transmitted between hosts. Eg: Ebola, influenza, rubella, chicken pox, hep a
Disease
A disorder of structure or function in a human, animal or plant. Especially one that produces specific symptoms or affects a specific location, not just a result of physical injury
Non-infectious disease
Result of a bodily function not working correctly. Caused by genetic, lifestyle and environmental factors.
Eg: Cancer, ADHD, OCD, Autism, dyslexia
Pathogen
A biological agent that causes a disease. Most are microorganisms. eg: bacteria, Protozoa, virus, prions, fungi, macroscopic parasites
Vector
A biological agent that transmits a pathogen but not necessarily harmed by it. Eg: mosquito carrying malaria
Transmission
The movement of a pathogen between hosts
Protozoa
Only a few are pathogens and can be seen with a light microscope. Eg: Amoeba. They are functionally independent individual cells and are single-celled. They have animal-like behaviours such as predation
Fungi
Only a few cause disease in humans. Mostly disease of the skin. Eg: ringworm they spread through spores and usually grow in warm, moist environments
Prions
Proteins that have a strange shape and cause other proteins to adopt their strange shape eg: BSE (mad cow disease)
Macroscopic Parasites
Can be seen without a microscope. Eg: tapeworm. They invade a host and take nutrients from it
Bacteria
Cause a lot of different diseases. Based on shape. Bacteria is microscopic and unicellular (one cell) . However many bacterias are good and important for the environment
Cocci , staphylocci , streptococci bacteria
Spheres , clusters , chains
Bacilli bacteria
Rods
Spirilla bacteria
Spirals
Virus
DNA wrapped in a protein shell. Hijack hosts cell and use the cell system to reproduce. Only can be seen with an electron microscope. Not ‘living’, needs host to reproduce. Can lay dormant for long time. Eg: polio
Antibiotics
Work by attacking the cell wall. Only effective on bacteria. Eg: penecillin
Outbreak
A disease that suddenly gets out of control. Can also refer to pandemic outbreaks and epidemic outbreaks eg: 2014 Ebola outbreak
Endemic
A disease that regularly effects a small number of people in the population. Eg: malaria
Epidemic
Higher than normal numbers are affected by a particular disease in a certain place. Eg: gastro
Pandemic
Outbreak that goes global, crossing boarders, everyone’s at risk. Eg: Ebola
Passive Immunity
Works by giving the person the antibodies to fight the antigen. Wears off quickly
Artificial immunity
Artificially stimulate the immune system as if it has had the disease before (even if it hasn’t) effective against bacteria and viruses
Natural Immunity
Your body (leucocytes) recognises diseases you’ve had before and creates antibodies to fight it
Active Immunity
Occurs with vaccination using dead, weakened or related form of the disease. Stimulates the immune response without the person getting the full disease.
How does vaccination work?
Dead, attenuated (weakened) or related forms of the disease are given to the person through vaccination. This stimulates the immune response without the person getting the full disease. The vaccination can wear off so boosters are needed every few years
Infectious disease Case study
Ringworm
Infectious disease Case study - causative pathogen?
Fungi
Infectious disease Case study - Vector/transmission
Contact with infected humans, animals or objects such as hats, hairbrushes, towels, clothing and sports equipment
Infectious disease Case study - Control of Transmission
Avoid contact with contaminated objects, humans and animals
Infectious disease Case study - Characteristic Symptoms
Begins as a flat ring-shaped rash and gradually gets larger. Can be dry and scaly or wet and crusted
Infectious disease Case study - Treatment and Management
Anti fungal medication
Physical Barrier
First line of defence - walls and moat
Physical Barrier - skin
Forms tough outer layer that microorganisms can’t penetrate. Covered in harmless bacteria that stop pathogens multiplying on surface
Physical Barrier - Mucous membrane
Digestive, respiratory, reproductive and urinary tract lined with thick mucous which contains antibody Immunoglobulin A. This stops pathogens invading
Physical Barrier - Cilia
‘Hairs’ that line the respiratory surface of the nose, trachea and bronchial tubes. Sweep mucous out nose opening and pharynx
Non-Specific Response
Second line of defence. Soldiers and archers
Non-Specific Response - inflammation response
Chemicals histamine and prostaglandins increase blood circulation around infected site. Skin goes red from blood circulation there and brings white blood cells to site. These break down pathogens and the toxins are carried away because of increased blood flow. Blood vessels dilate (get bigger) and become leaky. This allows toxins in and out of cells and allows white blood cells to move around infection site.
Non-Specific Response - phagocytosis
White blood cells (leucocytes) move from blood to infected area and devour foreign material (phagocytosis). Dead leucocytes and cells form yellowish discharge (pus)
Immune Response
Third line of defence - spies and assassins
Immune Response - Acquired immunity
Antigen (bad) engulfed by macrophage (phagocyte). Phagocyte displays antigen on surface. Antibody (T helper) recognises antigen and signals through chemical - cytokines to produce other antibodies (T killers) to kill antigen
Arguments for vaccination (8)
Prevent diseases, keep you healthy, they’re safe, won’t give you the disease it’s trying to prevent, protects your family, protects future generations, can help eliminate that disease, can save a life
Arguments against vaccination (7)
Unsafe, not adequately tested, overwhelm the immune system, religion, can cause autism and other problems, unnatural, cause/worsen asthma and allergies
Non-Infectious Disease Case Study
Cancer
Non-Infectious Disease Case Study - cause
Lifestyle, genes and environment
Non-Infectious Disease Case Study - Symptoms (15)
Unusual lump/swelling anywhere, unexplained pain/ache, problems peeing, persistent cough, coughing up blood, new mole or changes to mole, unexplained weight loss, blood in pee/poo, unusual breast changes, sore that won’t heal, difficulty swallowing, persistent bloating, croaky voice, persistent heartburn/indigestion, breathlessness
Non-Infectious Disease Case Study - treatment (4)
Surgery, radiotherapy, chemotherapy, hormone therapy
Non-Infectious Disease Case Study - management control
National cancer control programmes designed to reduce cancer cases and deaths and improve life quality of cancer patients
Herd Immunity
Some people, for various reasons, can’t be vaccinated so rely on others around them to be vaccinated to prevent exposure of the disease to them
Problems with viruses
Mutate new strains very quickly. Eg: influenza. This means a new vaccination needs to be created each flu season to update immunity to the current strain
Bacteria examples
Whooping cough, tetanus, diphtheria, typhoid fever
Virus examples
Measles, mumps, rubella, polio, chicken pox, herpes, warts
Fungi examples
Tinea, thrush, ringworm
Protozoa examples
Sporozoa, ciliates, flagellates, amoebae
Passive artificial immunity example
Injection antibodies
Passive natural immunity example
Breast feeding
Active artificial immunity example
Vaccination
Active natural immunity example
Get the infection
Genetic Disease
This is passed from parent to child (hereditary) eg: haemophilia or can include a predisposition to a particular disease eg: breast cancer
Lifestyle disease
Caused by engaging in activities that can cause disease. Eg: smoking can lead to cancer. Poor diet can lead to hypertension
Environmental disease
Caused by exposure to environmental hazards that cause disease. Eg: heavy metals (lead poisoning ect), asbestos, radiation
Difficulty of classifying non-infectious disease
It can be hard to find the cause for non-infectious disease as sometimes we don’t know what triggers it or there can be many things that do. There is always an overlap of the different causes of non-infectious disease as most aren’t just environmental, or genetic or lifestyle and there are many of these factors that can cause one disease.
Chromosomal disease
Chromosomes are the structures that hold genes. There are 23 pairs of chromosomes in the body (46 in total) if someone has extra chromosomes or non enough a disease is caused. A non-infectious chromosomal disease would be Down syndrome in which the person has three copies of the chromosome 21 instead of a pair of two
Gene Abnormality
Is a non-infectious disease which is inherited and caused by one or more abnormalities in the genome. Eg: autism, cystic fibrosis
Nutritional diseases
Can be caused by an insufficient take in of food or by the body not being able to absorb nutrients. It can also be caused by over eating. Nutritional disease is a form of lifestyle disease. Eg: obesity, malnutrition
Physiological Malfunction
These are diseases caused by organs or systems in the body malfunctioning and causing illness. Eg: asthma, diabetes, hypertension