Describe the trend in diseases spread by diffusion between 1991 and 2001.

Describe what is meant by “diffusion by relocation” with reference to a disease.

Explain the global distribution of diseases of poverty.

Referring to one or more diseases, discuss the factors that determine the relative importance of policies of disease prevention as opposed to policies of treatment.

Award 1 mark for the recognition that the number of cases of diseases spread by diffusion fell between 1991 and 2001, and an additional 1 mark for some quantification or recognition of anomaly.

Diffusion by relocation occurs when individuals infected with a disease move [1 mark] to a new, perhaps distant location and the disease spreads [1 mark].

Diseases of poverty include many infectious and parasitic diseases, as well as diseases related to vitamin and/or calorie deficiencies. The global distribution is related to economic and social development, though pockets of diseases of poverty can also exist in developed nations.

Factors include lack of access to adequate medical care because of costs and/or poor availability; poor quality of water supply; high levels of environmental pollution; poor levels of sanitation.

At least two distinct factors must be treated in detail for the award of the full 6 marks. Alternatively, a greater number of factors can be explained in less detail for the award of full marks.

Answers that simply describe the distribution should be limited to a maximum of 3 marks.

Alternative approaches should be considered on their merits.

No credit may be given for any explanations that relate directly to diseases of affluence (degenerative diseases, cancers, heart disease).

Numerous factors are relevant to this response, depending on the particular disease or diseases chosen. They include: relative costs per patient of treatment compared with prevention; cost, effectiveness and availability of disease-specific preventative measures such as vaccinations; whether or not the disease in question spreads by diffusion, and if so by which type of diffusion; potential long-term health or economic impacts of an outbreak of the disease in question; pressure from disease-specific non-governmental organizations.

Responses which show a good knowledge of one or more diseases and which discuss both prevention and treatment policies are likely to be credited at band D or above.

Marks should be allocated according to the markbands.

This was answered well with good use of quantification.

This was defined well with good use of supporting examples.

Again, there was a strong awareness here, with exploration of the factors of poverty, for example, water supply, sanitation, housing and/or food supply, mainly with reference to areas of the world that lack economic and social development. The best answers explained why some areas in developed nations are also subject to diseases of poverty.

There were very good case studies about policies of prevention and policies of treatment. Less well done was the consideration of the factors that determine the relative importance of each, for example, cost, effectiveness, availability of treatment or extent of the disease.