ENDEMIC: a disease habitually present in an area due to a permanent local cause e.g. malaria and cholera EPIDEMIC: a disease prevalent among a group at a particular time and produced by some causes not generally present in the area e.g. a sudden outbreak of flu. PANDEMIC: when an epidemic spreads across a vast geographical area e.g. cholera

ENDOGENOUS: a disease which is not infectious and traditionally associated with the lifestyle of people in the developed world and poses no threat to non affected persons in the community e.g. heart disease and cancers. EXOGENOUS: a disease which is infectious or contagious whereby the disease producing organism can spread to other individuals e.g. cholera, malaria and typhoid.

Climate – high temperatures can help spread stomach related diseases. Hot, wet conditions encourage the spread of infectious diseases. Cool, wet conditions can be linked to asthma and rheumatism. Water supplies – soft water (little calcium) has been linked to heart disease and water contaminated with sewage results in cholera and typhoid.

Vectors – flies and pests spread diseases such as malaria, river blindness and sleeping sickness. Soils - where soils are poor agriculture is limited leading to diet deficiency diseases (kwashiorkor, rickets). Remoteness – mountainous areas usually have poor communication and are more isolated – access to even basic health care is difficult.

Age – the very young and old are more susceptible to poor health, infections etc. Sex – females have longer life expectancies than males. Diet – too much, too little, balance of food types (protein, carbs). Diet deficiency diseases or obesity, cancers and heart disease.

Social factors – smoking, alcohol consumption, drug use. Living conditions – poor ventilation, dampness, overcrowding can help the spread of disease. Stress – more common in the Developed world and linked to lifestyle. Poor education – ignorance about the causes and treatments of preventable diseases.