Non-bacterial Pathogens- Topic 6 Flashcards
How are the different species of influenza virus classed?
Differences in haemagglutinin and neuraminidase
Mode of transmission of influenza
Droplet, direct contact, indirect contact, air
What genetic material does influenza have?
RNA
What is a zoonotic infection and what is it likely to cause?
Crosses the species barrier- pandemic
Mode of infection- influenza
Cilliated epithelial cells- lysis of cells cause symptoms of disease
What is the danger of having damaged cells from influenza?
Secondary infection
Why is it important to vaccinate against influenza annually?
Because RNA is more prone to mutation
What is the antigenic shift and what is the effect of this?
Genetic reassortment of the virus that results in a unique change- no one has immunity so prone to pandemic
What is antigenic drift?
Point mutation of haemagglutinin/ neuraminidase gene results in slight alteration- some immunity
Mode of infection- stem rust fungus
- spores land on host and use water to germinate
- asexual
- hyphae grows into the plant secreting enzymes to absorb nutrients
- hyphae forms a mycelium hidden in the stem or leaves
- teliospires affect Berberis
Mode of transmission- stem rust fungus- what does pattern show?
- spores carried by wind
- pattern of infection helps determine if source is local or distant (broad)
Pathogenic effect of stem rust
Red pustules break through epidermis which contain spores
- absorbs nutrients from plant
- epidermis breaks-plant cannot control transpiration- entry to other pathogens- dry out
- mycelium grows into vascular tissue absorbing plants water
- weakens stem
How can stem rust be controlled?
- increase spaces between crops= reduce moisture and increase distance the spore needs to travel
- reduce fertilisers as nitrates help rust
- use earlier maturing crops to beat rust life cycle
- remove wild berberis to interrupt life cycle
- fungicides
What is malaria?
Protozoa- single celled organisms spread by anopheles female mosquitos (vector)
Mode of infection- malaria
Parasite travels to liver- invades RBC and reproduces asexually- lysis of RBC- gametes infect mosquito