4.3.1.1 Communicable (infectious) diseases

What are pathogens?

Microorganisms that cause infectious disease

What are the four pathogens?

Viruses, bacteria, protists, fungi

How do viruses infect?

They move into cells and use the biochemistry of it to make many copies of itself which leads to the cell bursting and releasing all the copies into the bloodstream

How do bacteria infect?

They multiply very quickly through dividing by a process called binary fission and they produce toxins that can damage cells

How do protists infect?

Some are parasitic, meaning they use humans and animals as their hosts to live on and inside, causing damage

How do fungi infect?

They can either be single celled or have a body made of hyphae (thread-like structures) and they can produce spores which can be spread to other organisms

How are pathogens spread?

Direct contact and touching contaminated surfaces, drinking or coming into contact with dirty water, in the air and then breathed in

How can the spread of diseases be limited?

Improving hygiene like hand washing, reducing contact with infected individuals, using pesticides or insecticides to remove vectors and their habitat, vaccination