12.3 the transmission of communicable diseases

examples of direct transmission

• direct contact (contagious diseases)

• inoculation through a break in skin

• ingestion of contaminated food/drink

examples of indirect transmission

• fomites (inanimate objects transfer pathogens)

• droplet infection (droplets of saliva and mucus containing pathogens infect when inhaled)

• vectors (transmit from one host to another)

what factors can inc probability of catching a communicable disease

• overcrowded conditions

• poor nutrition

• compromised immune system

• poor disposal of waste

• climate change (inc temp)

• lack of trained health workers/insufficient public warning

how can disease be directly transmitted in plants

direct contact with any part of a diseased plant

how can disease be indirectly transmitted in plants

infected plants leave pathogens or reproductive spores in the soil

what are four types vectors

• wind (spores carry on the wind)

• water (spores swim on surface film of water on leaves)

• animals (carry spores plant to plant when feeding)

• humans (transmitted by hands, fomites)

factors that inc transmission of communicable disease in plants

• varieties of crops susceptible to disease

• over-crowding inc contact

• poor mineral nutrition

• damp, warm conditions inc spread

• climate change (inc rain and wind inc spread)