4.1.1 Communicable Disease and Prevention – Organisms That Cause Disease Flashcards
(11 cards)
What is a communicable disease?
A disease resulting from infection by a pathogen.
What is a pathogen? List the 4 examples.
A disease-causing organism.
They can be bacteria, fungi, viruses and protoctista (protists).
Describe 2 ways that pathogens can causes disease.
Damaging cells.
Producing toxins.
State how pathogens can be transmitted directly from host to host.
Physical contact e.g. touch, mixing of bodily fluids.
How are pathogens transmitted indirectly from one host to another?
Through vectors.
The faecal-oral route.
Droplet infection.
Spores carried in the air.
Give an example of a vector that is involved in transmission of a pathogen in animals.
Mosquito (transmits the parasite causing malaria)
Ticks (transmits the pathogen causing lyme disease)
How is Dutch elm disease transmitted indirectly?
A spore or bacteria attaches to an insect such as a beetle, which then moves from one tree to another.
How may climate change effect the distribution of vectors?
Changing climate may change the conditions of an area so that vectors can spread to new areas.
Why are there a greater variety of diseases in warmer climates?
Pathogens can grow and reproduce more rapidly in warm and moist conditions.
How may a lack of sanitation contribute to infectious diseases transmitted by the faecal-oral route?
If people are drinking/cleaning with water that has not been treated sufficiently, the water could be contaminated with a pathogen (from human sewage) and this could lead on to diseases such as cholera.
How can cramped living conditions contribute to transmission of a pathogen through droplet infection?
Pathogens in droplets released from an infected individual are more likely to be breathed in and infect someone else when living/working in cramped conditions.
