2 - disease dilemmas - global patterns of disease and factors that determine these

Epidemiological transition model

• Associated with Abdel Omran.

• Shows how disease patterns change as societies develop.

• Moves from an age of pestilence and famine, to receding pandemics, to degenerative and lifestyle diseases.

• Model is useful but not universal. Assumes all countries follow the same path.

• Better seen as a broad framework rather than a rigid sequence.

How standards of living (food, water, sanitation)

• Rising standards reduce susceptibility.

• Food strengthens the immune system

• Safe water reduced reduces water-borne infection

• Sanitation cuts the spread of pathogens

• Better housing and health care reduce death rates from communicable disease and increase life expectancy.

Disease in post-industrial societies

• People live long enough to develop degenerative diseases such as cancer and cardiovascular disease.

• Later stage is sometimes described as the stage of degenerative disease because treatment can prolong life even after diagnosis.

Higher prevalence of communicable diseases in LIDC countries

Poverty increases exposure and weakens resilience.

• Unsafe water, poor sanitation, poor housing, overcrowding and weak healthcare can all increase infection risk.

• Undernutrition and malnutrition weaken immune systems, making people more vulnerable to diseases such as TB, malaria, cholera and respiratory infections.

• Geography - many LIDCs are in tropical climates where rainfall, humidity and temperature favour vectors such as mosquitoes and parasites

Higher prevalence of non-communicable diseases in AC’s

Sanitation, vaccination and treatment are stronger. They have higher levels of non-communicable because populations are older and lifestyles are more sedimentary.

Over nutrition, obesity, alcohol consumption, smoking, low exercise and diets high in salt, fat and sugar contribute to cardiovascular disease, diabetes and certain cancers.

India - environmental and human causes

Major outdoor pollutants include nitrogen dioxide, sulphur dioxide, ozone and particulate matter from motor vehicles, coal-fired power, factories, brick kilns and urban congestion.

Indoor pollution is also severe where biomass, animal dung and paraffin are still used for cooking and heating.

Environmental pollutions figures in India

• Particulate matter smaller than 2.5 is dangerous because it penetrated deep into the lungs and bloodstream which increases cancer risk, respiratory illness and cardiovascular stress.

• Delhi - safe WHO levels around 10micrograms per m3, Delhi averages around 40 and has exceeded 600 in winter.

• One of the world’s most polluted megacities. (Delhi)

• Lung function - 40% lower

• Hypertension - 40% higher

• Lung cancer risen roughly 70% in city.

Air pollution is not just an environmental problem

Becomes a long term public health issue that increases treatment costs, lost productivity and pressure on hospitals.

Smoking vs pollution in India

Smoking remains biggest cause of lung cancer but now 20% of lung-cancer cases are not amongst non-smokers.

Data shows rises for both men and women

• National responses to Delhi pollution

• Retrofitted chimneys in Bihar

• Metro-expansion in several cities

• City to petrol and diesel subsidies

• Restrictions on stubble burning and emissions-trading approaches in Gujarat.

Global responses to Delhi pollution

Wider climate agreements and international pressure for tighter air quality standards.

Rapid urbanisation, vehicle growth and industrial expansion often outpace policy enforcement.

Overall - Delhi

India shows that mitigation is possible but success is uneven because economic growth, energy demand and weak regulation keep pushing exposure back up