Communicable diseases Flashcards
Can you explain the definition of a vector?
- A vector carries pathogens from one organism to another.
Can you explain the modes of action of different pathogens?
- Viruses take over the cell metabolism. Viral genetic material gets into host cell and is inserted into host DNA.
- Some protoctista take over cells as well and break them open as the new generation emerge. They don’t take over the genetic material of the host cell. They however, digest and use cell contents as they reproduce. An example of this would be malaria.
- Fungi digest living cells and destroy them. Combines with the response of the body combined with the response of the body to damaged cause by fungus gives disease.
- Bacteria and fungi produce toxins that might damage host cells by breaking down cell membranes, some damage or inactivate enzymes and can interfere with host cell genetic material so cells cannot divide.
What pathogen causes ring rot?
- Gram positive bacteria called ‘Claver bactermichiganensis’
What pathogen cause potato-blight?
- The fungus-like protoctist called ‘Phytophthora infestans’
What pathogen causes black sigatoka?
- A fungus called ‘Mycosphaerella fijiensis’
What pathogen causes TB?
- Bacteria called ‘Mycobacterium tubercolosis’ and ‘M.bovis’.
What pathogen causes bacterial meningitis?
- A bacteria called ‘Streptococcus pneumoniae’
What pathogen causes Influenza (flu)?
- A virus called ‘orthomyxoviridae’
What pathogen causes malaria?
- Caused by the parasite ‘Plasmodium’ that’s spread by bites of Anapheles mosquito
What pathogen causes Ring-worm?
- Caused by fungus called ‘Tricophyton verrucosum’.
What pathogen causes Athlete’s foot?
- Caused by fungus called ‘Tinia pedia’.
Can you explain the forms of direct transmission? : ANIMALS
CHALLENGE: give examples of illnesses that are tied with these
- Direct - HIV, Ring worm, diarrhoeal diseases
- Inoculation - Rabies, septicaemia
- Ingestion - Amoebic dysentery
Can you explain forms of Indirect transmission? - ANIMALS
CHALLENGE: Give examples of illnesses tied with these
- Fomites - Athlete’s foot
- Droplet infection - Tubercolosis (TB)
- Vectors - Malaria
Can you explain forms of direct transmission? : PLANTS
CHALLENGE: Give examples of illnesses tied with this
- Soil contamination - ring rot spores contaminate soil and live long after plants are removed, new plants planted in soil become infected by this bacterial disease.
Can you explain forms of indirect transmission? : PLANTS
CHALLENGE: Can you give examples of illness tied with this.
- Water allows spores to ‘swim’ on it’s surface for example potato blight
- Wind carries fungal spores - black sigatoka
- Animals carry pathogens and spores - aphids inoculate the pathogen directly into plant tissues, are an invasive species as well because of this
- Humans (farmers mostly) transmit spores/pathogens with hands and clothing - TMV survives for years in tobacco products and ring rot can survive on potato sacks.
What are the chemical defences of plants?
- antibacterial compounds - antibiotics, plant proteins that disrupt bacterial and fungal cell membranes
- insecticide - caffeine is toxic to insects and fungi
- insect repellants pine resin and citronella from lemon grass
- anti fungal compounds - caffeine is toxic to fungi and insects, produce chitinase to break down chitin which is fungi cell membrane
- anti-oomycete - can produce glucanase to break down polymer ‘glucan’ which is found in oomycete cell wall
- general toxins - some plants make cyanide as a byproduct, cyanide is toxic to most living things
What are the common range of antibiotics used?
NAME ALL 8!!
- Streptomycin
- Amoxicillin
- Cephalosporins
- Tetracyclines
- Sulfonamides
- Polymixines
- Ampicillin
- Vancomycin
What do interleukins do?
- Stimulates B cell production, this increases rate of antibody production
- Produces different types of T cells
- Attracts and stimulates macrophages to pathogens with antigen-antibody complex
What is the source of penicillin and its action?
- found on mould growing on melons
- antibiotic - one of the first effective treatment against many common bacterial diseases.
What is the source of docetaxel/paclitaxel and its action?
- originally from yew trees
- treatment for breast cancer
What is the source of Aspirin (acetylsalicylic acid) and its action?
- based on compounds feom sallow (willow) bark
- painkiller, anticoagulant, anti-pyretic (reduces fever)
What is the source of Prialt and its action?
- derived from venom of cone snail from oceans around australia
- new pain-killing drug 1000 times more effective than morphine
What is the source of Vancomycin and its action?
- derived from soil fungus
- one of the most powerful antibiotics
What is the source of Digoxin and its action?
- based on vigitoxin but originally extracted from foxgloves
- powerful drug used to treat atrial fibrillation and heart failure .
