Epidemiology - Basic Epidemiology
1. What is Epidemiology?
SummaryIn summary, epidemiology is a tool that allows us to:
- Identify the causes [aetiology] of a disease or group of diseases. This is done by attempting to correlate epidemiological findings with the discoveries made by workers in scientific disciplines such as genetics, molecular biology, biochemistry, histopathology and microbiology
- Assist investigators in the testing of theories about information collected during medical research in the laboratory and clinical observations
- Decide whether disease prevention programmes are working and for developing new strategies for the benefit of occupational and public health.
Epidemiology, therefore, is intended to help us to establish programmes that will prevent, or at least control the development and spread of disease or injury, and is therefore closely concerned with both occupational and public health issues. Epidemiologists are not only concerned with morbidity (disease) and mortality (death), but also in ways in which health can be improved and good health maintained. It could be said that health promotion is the end in view for many epidemiologists, and epidemiological studies are the pathway to that goal. The three reasons given overlap and their purpose is to act as guidelines to facilitate clear thinking about epidemiology.
The study of epidemiology encompasses many disciplines and a large number of factors must be considered in any epidemiological investigation.
- Knowledge of social factors is important, since a person's living conditions can influence their susceptibility to disease. For example the level of wealth or poverty can affect the quality of a person's health, as can factors such as diet, occupation and educational background, all of which are influenced by the financial solvency of the individual. The specific location where individuals live is also important, since their living environment, whether polluted or clean, for example, has considerable effect on their health.
- Lifestyle factors such as drinking, smoking, consumption of specific food types,
level of exercise, or even drug taking can be significant in two ways in respect of occupational disease:
a) They can influence the susceptibility of an individual to disease
b) They can interact with substances to which an individual is exposed at work, e.g. synergism.
Characteristics such as ethnicity, gender and age are also of interest to epidemiologists, as these factors can have a bearing not only on how a person responds to disease, but also if they are more likely to suffer from a particular disease in the first place. Genetic factors are also of significance, since some diseases are linked with the genetic profile of the individual.