Commincable Diseas - Module 4 Flashcards
What is a communicable disease and what causes it?
A communicable disease is an infectious/contagious disease caused by pathogens
What are the 4 types of pathogens?
- Bacteria
- Virus
- Fungi
- Protist
How do virus’ damage cell host?
Virus takes over the metabolism and the viral DNA is inserted into the host DNA - making more virus which will eventually burst out the cell destroying it
How do protists damage the host cell?
Protists digest the contents of the cell as they reproduce
How do bacteria damage host tissues?
Produce toxins that cause disease
What is ring rot? Which pathogen causes it?
Ring rot, bacterial disease, damages leaves, tubers and fruit of potatoes and tomatoes
What is TMV? What pathogen causes it?
Tobacco mosaic virus, TMV, a virus
Damages leaves, flowers and fruit as it stunts growth
What is potato blight? What pathogen causes it?
Potato blight, affecting tomatoes and potatoes, is caused by a fungus
The hyphae destroy leaves and tubers
What is black Sigatoka? What pathogen causes is?
Black Sigatoka is a fungal banana disease
The hyphae turns the leaves black, reducing yield of bananas
What is TB? And what pathogen causes it?
Tuberculosis (TB) is a bacterial disease
Damages lung tissues and suppresses immune system
Is TB preventable?
Yes - there is a vaccine
Is TB treatable?
Yes - there is antibiotics
What is bacterial meningitis? What pathogen causes it?
Bacterial meningitis is a bacterial infection of the membrane of the brain
Causes blood poisoning resulting in rapid death
What are the symptoms of bacterial meningitis?
Blotchy red rash that does not disappear when a glass is pressed on it
Is bacterial meningitis preventable?
Yes - there is a vaccine
Is bacterial meningitis curable?
Yes there are antibiotics
What is HIV/AIDS? And what pathogen causes it?
HIV is caused by a virus
It destroys the immune system leaving sufferers vulnerable to other diseases
Is HIV/AIDS preventable?
Safe practices; protected sex, don’t share needles, don’t contaminate blood
Is HIV/AIDS curable?
No - there is no vaccine but anti-retroviral drugs slow the progression of the disease
What is influenza? What pathogen causes it?
Influenza is a viral infection
It destroys ciliated epithelial cells leaving airways open to infection
What is malaria? What pathogen causes it?
Malaria is caused by the protoctist plasmodium
And it is transferred by mosquitoes (vector)
It invades blood cells, liver and brain and it makes people weak and vulnerable to other infections
Is malaria preventable?
There is no vaccine but to control malaria the vectors need to be controlled through mosquito nets, insectasides
What is ring worm? What pathogen causes it?
Ring worm is a fungal disease
Causes crusty infection areas of skin
How is ring worm cured?
Antifungal creams
What is athletes foot and which pathogen causes it?
Athletes foot is a fungal disease, a form of human ring worm
Causes itchy and sore areas between he toes
How is athletes foot cured?
Antifungal creams
What is direct transmission?
When a pathogen is transferred directly from one individual to another
Describe the 3 ways of direct transmission
- Direct contact
Kissing, exchange of bodily fluids, skin to skin contact - Inoculation
Break in the skin, animal bite, puncture wound (sharing needles) - Ingestion
Contaminated food or drink
What is indirect transmission?
Where a pathogen travels between individuals indirectly
Describe the 3 ways of indirect transmission
- Fomites
Bedding, socks, cosmetics being shared - Droplet infection (inhalation)
Coughing, sneezing particles then being breathed in - Vectors
Something that transmits communicable disease (mosquitoes)
Can communicable disease be passed between human and animals?
YES - bird flu
What factors affect the probability of catching communicable disease?
- Overcrowded living conditions
- Poor nutrition
- Compromised immune system
- Infrastructure
- Socioeconomic factors (lack of trained healthcare workers)
What is direct transmission in plants?
Direct contact of a healthy plant with any part of a diseased plant
Describe the two ways of indirect transmission in plants?
- Soil contamination
Infected plants leave pathogens or spores in soil infecting next crop to be planted there - Vectors
Wind carrying spores, water, animals, humans
What factors affect the chances of plants being infected with communicable disease?
- Planting crops susceptible to disease
- Over crowding
- Poor mineral and nutrition
- Damp and warm conditions (increase survival and spread of pathogens)
Why do plants not heal diseased tissues?
They are continually growing and meristems can replace damaged parts
What is Callose and what does it do?
Callose is a polysaccharide that is deposited between cell wall and cell membrane, plasmodesmata and phloem to stop pathogen entering cells around infection site