Disease management: strategies, evaluation

Disease and Geography (Cambridge AS & A Level Geography 9696 – Paper 4: Global Themes)

Objective

To understand the range of disease‑management strategies, evaluate their effectiveness and limitations, and apply this knowledge to real‑world geographical contexts, fully meeting the Cambridge AS & A Level syllabus requirements.

1. Key Geographical Concepts for Disease

All concepts required by the syllabus are listed below together with the section(s) where they are applied. This checklist helps you verify coverage when studying or answering exam questions.

Concept	Definition (Geography focus)	Where it is used in these notes
Scale	Local, regional, national, global extent of a phenomenon.	Section 2 (Epidemiological transition), Section 5 (Management strategies)
Change over time	How disease patterns and responses evolve.	Section 2 (Timeline), Section 8 (Case studies)
Place	Physical and human characteristics that affect vulnerability.	Section 3 (Why geography matters), Section 5.1 (Prevention examples)
Spatial variation	Differences in incidence, prevalence or risk across space.	Section 4 (Spatial patterns), Section 7 (Evaluation table)
Cause‑and‑effect (systems)	Interactions between climate, vectors, behaviour, health outcomes.	Section 3 (Drivers), Section 9 (Diagram description)
Environmental interaction	How land‑use, water management and built environments influence disease.	Section 3 (Drivers), Section 5 (Strategies)
Challenges & opportunities	Constraints (poverty, governance) and assets (technology, community networks).	Section 3 (Drivers), Section 5.5 (Policy & governance)
Diversity, equality & inclusion	Influence of gender, ethnicity, disability and socio‑economic status on exposure and access.	Section 3 (Socio‑economic conditions), Section 6 (Evaluation criteria)

2. Epidemiological Transition & Disease Burden

2.1 Stages of the Transition

Stage	Dominant disease groups	Typical geographic examples	Scale of impact
1. Age of pestilence and famine	Acute infectious diseases, high infant mortality	Pre‑industrial Europe, sub‑Saharan Africa (early 20th c.)	Local to regional
2. Age of receding pandemics	Declining infectious disease, rise of chronic infections (TB, HIV)	Mid‑20th c. Latin America, parts of Asia	National
3. Age of degenerative & man‑made diseases	Non‑communicable diseases (NCDs) dominate	High‑income countries, urbanising middle‑income nations	National to global
4. Age of delayed degenerative diseases	Further reductions in mortality, ageing populations	Japan, Western Europe, increasingly in China	Global

2.2 Measuring Disease Burden

• Disability‑Adjusted Life Years (DALYs) = Years of Life Lost (YLL) + Years Lived with Disability (YLD).
• High‑income countries: >70 % of DALYs from NCDs.
• Low‑ and middle‑income countries: >40 % of DALYs still from infectious diseases, especially in rural & peri‑urban settings.

2.3 Timeline of Major Global Disease Events (Change‑over‑time)

• 1918 – Spanish flu pandemic (global viral outbreak, high mortality).
• 1950‑60s – Smallpox eradication campaign (global vaccination effort).
• 1980s – HIV/AIDS emergence (new chronic infectious disease, worldwide spread).
• 1990s – Rise of non‑communicable diseases in rapidly urbanising Asia.
• 2003 – SARS outbreak (highlighting rapid international travel as a driver).
• 2014‑16 – West Africa Ebola epidemic (zoonotic spill‑over, weak health systems).
• 2020‑23 – COVID‑19 pandemic (global diffusion, massive policy response).

3. Geographical Drivers of Disease

Each driver is presented as a sub‑section for quick reference and linked to concrete examples.

3.1 Physical Environment

• Climate – Temperature & rainfall determine vector ranges (e.g., malaria expands northward with warming).
• Altitude – Mosquito density drops >2 000 m, but high‑altitude pulmonary oedema becomes a risk.
• Water bodies – Stagnant water creates breeding sites for Aedes (dengue, Zika).

3.2 Human‑Environment Interaction

• Urbanisation – Overcrowded housing, inadequate drainage → dengue, cholera.
• Land‑use change – Deforestation brings people into contact with sylvatic reservoirs (Ebola, Nipah).
• Water management – Irrigation canals can become malaria habitats.

3.3 Socio‑Economic Conditions

• Poverty – Limited access to clean water, sanitation, health services.
• Education – Influences health‑seeking behaviour and vaccine uptake.
• Employment patterns – Seasonal migrant workers can spread infections across regions.

3.4 Political & Cultural Contexts

• Governance capacity – Ability to organise vaccination campaigns, enforce quarantine.
• Cultural practices – Traditional burial rites (Ebola) or gender norms affecting exposure.
• Policy frameworks – International Health Regulations, national disease‑control legislation.

3.5 Climate Change

• Rising temperatures expand the geographical range of vector‑borne diseases (malaria, dengue, Lyme disease).
• Altered precipitation patterns create new breeding habitats (e.g., flood‑plain malaria).
• Extreme weather events can disrupt health infrastructure, increasing vulnerability.

4. Spatial Patterns of Disease

4.1 Mapping Tools

• Distribution maps – Show incidence/prevalence per unit area; identify hotspots.
• Heat‑maps (GIS) – Real‑time visualisation of case density.
• Diffusion models
  • Expansion diffusion – outward spread from a source (COVID‑19).
  • Hierarchical diffusion – moves from larger to smaller settlements (influenza).
  • Relocation diffusion – carried by human movement (imported malaria).

4.2 Map‑Reading Tips for Exams

1. Identify colour gradients – intensity of disease.
2. Look for clustering – possible environmental or socio‑economic drivers.
3. Overlay relevant layers (e.g., rainfall, population density) to infer causation.

5. Main Disease‑Management Strategies

Each strategy is described with typical geographical contexts, examples, and links to the evaluation criteria.

5.1 Prevention

• Vaccination programmes
  • Cold‑chain logistics essential in remote high‑altitude or island settings.
  • Example: Polio eradication in India – door‑to‑door campaigns with portable cold boxes.
• Vector control
  • Insecticide‑treated nets (ITNs) – rural tropical villages.
  • Indoor residual spraying (IRS) – peri‑urban areas with permanent housing.
  • Larviciding & environmental management – drainage of stagnant water in flood‑prone lowlands.
• Health education & behaviour change – school‑based campaigns in densely populated urban slums.
• Improved Water, Sanitation and Hygiene (WASH) – critical in informal settlements and refugee camps.

5.2 Surveillance, Early Detection & GIS Mapping

• Routine national reporting systems (e.g., Integrated Disease Surveillance Programme, Kenya).
• Sentinel sites & laboratory networks at border regions with high cross‑border movement.
• GIS & spatial analytics – real‑time heat‑maps for megacity outbreaks (e.g., Shanghai COVID‑19 dashboard).

5.3 Containment & Control

• Quarantine & isolation – most effective on islands or regions with natural entry points.
• Travel restrictions & border screening – early stages of emerging pandemics.
• Mass drug administration (MDA) – endemic rural zones (lymphatic filariasis in Southeast Asia).
• Environmental management – drainage of breeding sites in flood‑plain agriculture.

5.4 Treatment, Care & Health‑System Strengthening

• Antimicrobial therapy – requires reliable drug supply chains.
• Supportive care & case management – well‑equipped hospitals in urban centres.
• Training of health personnel – community health workers in remote highland villages.
• Health‑system strengthening – decentralised primary care, tele‑medicine for isolated populations.

5.5 Policy, Governance & International Cooperation

• National disease‑control programmes coordinated by ministries of health.
• International frameworks (WHO International Health Regulations) – guide cross‑border response.
• Public‑private partnerships – vaccine research, production and distribution.
• Legislation & regulation – bans on open defecation, building‑code enforcement to reduce vector habitats.

6. Evaluation Criteria (AO3)

Use these six criteria when assessing any disease‑management approach. They align with the Cambridge assessment objectives for Paper 4.

Criterion	Key considerations for evaluation
Effectiveness	Reduction in incidence, prevalence, mortality or DALYs; speed of impact.
Cost‑effectiveness	Financial resources required vs. health gains (e.g., cost per DALY averted).
Equity	Access for vulnerable, remote or marginalised groups; gender and socio‑economic fairness.
Sustainability	Long‑term viability, environmental footprint, dependence on external funding.
Acceptability	Cultural, religious and political support; community attitudes.
Feasibility	Logistical, technical and human‑resource capacity; infrastructure requirements.

7. Comparative Evaluation of Strategies

Strategy	Strengths (linked to criteria)	Weaknesses (linked to criteria)	Geographic contexts where it works best
Vaccination programmes	High effectiveness; herd immunity; long‑term protection (Effectiveness, Sustainability).	Cold‑chain needs; upfront cost; vaccine hesitancy (Cost‑effectiveness, Acceptability).	Urban & peri‑urban areas with health infrastructure; mobile teams can reach remote highland villages.
Vector control (ITNs, IRS, larviciding)	Directly reduces transmission; relatively low cost per person (Effectiveness, Cost‑effectiveness).	Insecticide resistance; requires community compliance (Feasibility, Acceptability).	Tropical & subtropical regions; rural settlements near water bodies; peri‑urban slums.
Surveillance & GIS mapping	Rapid hotspot detection; informs targeted response (Effectiveness, Feasibility).	Data quality, technical expertise, equipment costs (Cost‑effectiveness, Feasibility).	Areas with mobile populations, cross‑border movement, and megacities.
Quarantine & travel restrictions	Can halt early spread of emerging infections (Effectiveness).	Economic disruption; enforcement challenges; political unpopularity (Acceptability, Sustainability).	Island nations, regions with limited entry points, early pandemic phases.
Mass drug administration (MDA)	Rapid community‑wide parasite reduction (Effectiveness, Cost‑effectiveness).	Risk of drug resistance; requires >80 % coverage (Feasibility, Sustainability).	Endemic rural zones with focal transmission (e.g., lymphatic filariasis in SE Asia).
Health‑system strengthening	Improves diagnosis, treatment, prevention across diseases (Effectiveness, Equity).	Long‑term investment; may be hampered by weak governance (Feasibility, Sustainability).	Low‑resource countries; remote highland or island settings where primary care is scarce.
Policy & governance interventions	Creates legal/financial frameworks; facilitates coordination (Effectiveness, Sustainability).	Implementation depends on political will; can be slow to change (Feasibility, Acceptability).	National‑level programmes; regions with strong central authority or effective regional cooperation.

8. Case Study Examples (Geographically Linked)

• Malaria control in sub‑Saharan Africa – Integrated ITNs, indoor residual spraying, and seasonal malaria chemoprevention. Success tied to community mobilisation, reliable supply chains, and targeting lowland floodplains.
• Polio eradication in South Asia (India & Pakistan) – Door‑to‑door vaccination, GIS tracking of missed children, political commitment, and engagement of local religious leaders to overcome hesitancy in remote districts.
• Ebola outbreak, West Africa (2014‑16) – Initial surveillance failure; later containment through strict quarantine, safe burial practices, and rapid establishment of treatment centres in urban hubs (Freetown, Conakry). Highlighted governance, cultural practices and health‑system capacity.
• Dengue emergence in rapidly urbanising Southeast Asian megacities – Unplanned housing, inadequate drainage, and high human density created breeding sites for Aedes aegypti. Control relied on community‑based source reduction and targeted insecticide spraying in high‑risk neighbourhoods.
• COVID‑19 response in island nations (New Zealand, Taiwan) – Early border closures, robust testing & contact tracing, clear public communication. Geographic isolation facilitated strict quarantine; GIS dashboards visualised spread.

9. Suggested Diagram

10. Summary

Disease management is fundamentally a geographical challenge. By analysing scale, spatial variation, and the interplay of physical, socio‑economic and political factors, geographers can design and evaluate interventions that are:

• Effective in reducing disease burden,
• Cost‑effective and sustainable,
• Equitable and culturally acceptable, and
• Feasible within the logistical realities of each location.

Applying the evaluation criteria and recognising the strengths and limitations of each strategy in specific geographic contexts enables policymakers to tailor responses that protect health while respecting environmental and social realities.