Topic 3: Pathogens

Question 1

what is an infectious disease?

Answer 1

any illness caused by the invasion of the body by harmful organism

Question 2

Name the different types of pathogens. How do they cause infectious disease?

Answer 2

1. Bacteria
2. Viruses
3. Protozoa
4. Fungi
5. Prions

They all stop cells functioning normally causing disease

Question 3

define infection

Answer 3

occurs when an infectious agent such as bacterium, virus, protozoan, or fungus that can be passed onto others.

Question 4

What is the difference between a cellular and non-cellular pathogen? Give examples of each.

Answer 4

Cellular Pathogens consists of living cells - bacteria, fungi, protozoans

Non-cellular are not living cells - Viruses and Prions

Question 5

2 ways pathogens can enter the body

Answer 5

1. Gastrointestinal Tract - food that is contaminated with micro-organisms (cholera, typhoid fever)
2. Respiratory Tract - airborne viruses that are inhaled from other people’s expelled mucus eg whooping cough, chickenpox

Question 6

3 ways pathogens can be spread

Answer 6

1. Contact
2. Vehicle
3. Vector

Question 7

What is contact transmission?

Answer 7

1. airborne droplets eg sneezing
2. sexual contact
3. direct contact

Question 8

What is vehicle transmission

Answer 8

a non-living object that can carry an agent
1. food and waterborne
2. carried in blood

Question 9

What is vector transmission

Answer 9

disease that results from an infection transmitted to humans and other animals by fleas, mosquitoes

Question 10

How can the spread of infection be reduced?

Answer 10

1. Vaccines
2. Antimicrobial drugs
3. Good personal hygiene and sanitation
4. Protection against mosquitoes (insect repellent)
   5.Quarantine (isolation)