What are the global patterns of disease and can factors be identified that determine these? Key Idea 1b: There is a relationship between physical factors and the prevalence of diseases which can change over time. Learning Objectives: To consider how climate change influences the diffusion of emerging infectious diseases.

What does this map show? Climate change – increases in temperature, rainfall and humidity – has stimulated the transmission of vector-borne diseases and extended their geographic range.

Tasks Read page 341. What is WNV? Where and when was it first identified? Where is it now found? How has climate change facilitated the diffusion of this disease to increase its geographic range? What is Lyme disease? Explain how climate change has facilitated the spread of Lyme disease to a wider geographic area. What is trypanosomiasis? Explain how climate change has facilitated the spread of trypanosomiasis to a wider geographic area.

What are the global patterns of disease and can factors be identified that determine these? Key Idea 1b: There is a relationship between physical factors and the prevalence of diseases which can change over time. Learning Objectives: To consider the conditions required to facilitate the spread of zoonotic diseases.

What are zoonotic infections? List as many as you can- identify the carrier as well as the disease. Malaria – mosquitoes. Sleeping sickness – tsetse fly Bilharzia – flatworm/freshwater snails. WNV – Culex mosquito. Dogs – rabies. Poultry – Asian bird flu

Read page 342 and make relevant notes. What conditions increase the probability of zoonotic disease being spread to humans? Read page 342 and make relevant notes. Unrestricted movement of infected wild animals. Ineffective controls on the movement of diseased domestic animals. Urbanisation which creates suitable habitats for foxes, skunks etc. Limited vaccination of domestic animals. Limited control of feral animals in urban areas e.g. cats; pigeons; dogs. Hygiene and sanitation is poor and drinking water is often contaminated by animal faeces; blood & saliva. Ponds of stagnant water encourage insect vectors such as mosquitoes to breed. There is prolonged contact between humans and animals e.g. poultry farms and Asian flu.

Exam style Questions Using examples, explain how climate change could influence the spread of disease to a wider geographical area. [6 marks]. Use examples to explain why the probability of zoonotic diseases being transmitted to humans is likely to increase? [6 marks].