Disease Flashcards
What is a communicable disease?
Disease that can be passed from one organism to another.
What pathogens cause communicable diseases?
Bacteria, viruses and fungi
What are pathogens?
Disease-causing microbes.
What are some examples of communicable diseases?
HIV (which leads to AIDS)
Colds and flu
Human papilloma virus (HPV)
Salmonella food poisoning
Tuberculosis
Chlamydia
Athlete’s foot
Potato blight
What type of pathogen causes HIV?
Virus
How is HIV spread?
Exchange of bodily fluids during sex.
Infected blood.
How is HIV controlled, prevented and treated?
Using condom reduces risk of infection.
Drug addicts not sharing needles.
Currently controlled by drugs.
What type of pathogen causes colds and flu?
Virus
How are colds and flu spread?
Airborne droplet infection.
How are colds and flu controlled, prevented and treated?
Flu vaccination for targeted groups.
What type of pathogen causes human papilloma virus (HPV)?
Virus
How is HPV spread?
Sexual contact.
How is HPV controlled, prevented and treated?
HPV vaccination given to 12 to 13 year old girls to protect against developing cervical cancer.
What type of pathogen causes salmonella food poisoning?
Bacterium
How is salmonella spread?
From contaminated food.
How is salmonella controlled, prevented and treated?
Always cooking food thoroughly.
Not mixing cooked and uncooked foods can control spread.
Treatment with antibiotics.
What type of pathogen causes tuberculosis?
Bacterium
How is tuberculosis spread?
Airborne droplet infection.
How is tuberculosis controlled, prevented and treated?
BCG vaccination.
If contracted, treated with drugs, including antibiotics.
What type of pathogen causes chlamydia?
Bacterium
How is chlamydia spread?
Sexual contact.
How is chlamydia controlled, prevented and treated?
Using condom will reduce risk of infection.
Treatment with antibiotics.
What type of pathogen causes athlete’s foot?
Fungus
How is athlete’s foot spread?
Contact
How is athlete’s foot controlled, prevented and treated?
Reduce infection risk by avoiding direct contact in areas where spores likely to be present, e.g. wear flip flops in changing rooms / swimming pools.
What type of pathogen causes potato blight?
Fungus
How is potato blight spread?
Spores spread in air from plant to plant, particularly in humid and warm conditions.
How is potato blight controlled, prevented and treated?
Crop rotation and spraying plants with fungicide.
What is the cost to the NHS on treating communicable disease?
Cost of medication (treatment / drugs).
Cost of salaries (doctors / nurses / other staff).
Upkeep of hospitals.
What is the cost to society of communicable diseases?
Missed days from work / school.
Mental health issues.
Family stress.
What are the first lines of defence against communicable disease in the body?
Skin
Tears and salvia
Hydrochloric acid in stomach
Ciliated epithelial cells
Eyes / eye lids
How does the skin defend against communicable diseases?
Physical barrier (scab formation).
How does tears and salvia defend against communicable diseases?
Lysosomal enzymes that hydrolyse bacteria.
How does the hydrochloric acid in the stomach defend against communicable diseases?
Low pH denatures enzymes and destroys pathogens.
How do ciliated epithelial cells defend against communicable diseases?
Mucus trap dust / dirt / pathogens.
Ciliate waft to back of throat to be coughed out.
How do the eyes / eye lids defend against communicable diseases?
Blink reflex - physical barrier.
What are the 3 types of white blood cells that carry of secondary immune response?
Lymphocytes
Phagocytes
Memory cells
What is a lymphocyte?
A type of white blood cell that produces antibodies.
What is an antigen?
A distinctive marker on a microorganism that leads to the body producing specific antibodies.
What is an antibody?
Structure produced by lymphocytes that has a complementary shape (can attach to) antigens on a particular microorganism.
What is a memory lymphocyte?
Special type of lymphocyte that can remain in the body for many years and produce antibodies quickly when required.
How do the lymphocytes help to destroy microorganisms that have entered the body?
- Antigens on microorganisms cause lymphocytes to produce antibodies.
- Antibodies complementary in shape to antigens.
- Antibodies latch onto antigens, linking them together.
- Immobilises (clumps) microorganisms and then can be destroyed.
How do the phagocytes help to destroy microorganisms that have entered the body?
Carry out phagocytosis by engulfing and digesting the clumped microorganisms.
What does clumping the harmful microorganisms do?
Prevents them from moving around body, and flags them up for phagocytes to engulf and digest them.
What does immunity mean?
Antibody levels are high enough (or high enough levels can be produced quickly enough) to combat microorganism infections.
What are the types of artificial immunity?
Active
Passive
Where does passive immunity come from?
Antibodies from source directly injected in body, e.g. tetanus.
Where does active immunity come from?
Vaccination of dead / attenuated does of pathogen, e.g. MMR vaccination.
What are the characteristics of passive immunity?
Fast acting.
Only lasts a short period of time.
What are the characteristics of active immunity?
Slow acting.
Provides long-lasting protection.
What are some examples of passive immunity?
Breastfeeding passing antibodies to baby.
Anti-venom for snake-bites.
What are some examples of active immunity?
Body producing antibodies to combat an infection.
Vaccines.
What does immunity involve?
Memory cells in secondary immune response.
What are the 2 types of natural immunity?
Innate
Acquired
Where does innate immunity come from?
Colostrual route - from mother to baby via breast milk.
Placenta route - from mother to foetus via placenta.
Where does acquired immunity come from?
Develops during life as result of infection / contact with pathogen and recovering, e.g. chicken pox.
What are the characteristics of innate immunity?
Antibodies are already made.
Fast acting.
Short lived immunity.
What are the characteristics of acquired immunity?
Antibodies actively produced.
Slow acting.
Longer lived immunity.
What is a vaccination?
Injection of dead or midwifed pathogens with purpose of raising antibody and memory lymphocyte levels in blood.
How do vaccinations work?
Antigens on dead or modified pathogens cause body to produce antibodies.
Raises antibody levels in blood; if body becomes infected with same pathogens again later, memory lymphocytes already present in body to rapidly produce antibodies to prevent disease developing.
