Issuu on Google+

Introduction ♦ The study of disease distribution and

causation remains central to epidemiology. ♦ The techniques of epidemiology have a wider application. ♦ Cover many more important areas to: - disease - Health - Health services


♌ Epidemiology can be defined as:

- Means of learning. - Asking or asking question and getting answers that lead to further questions .


Uses of epidemiology 1. Control of disease by: ♦ pt isolation ( in dealing with infectious

diseases ), ♦ using frequency of the disease to give priority to some places over others. and ♦ by measuring incidence of the disease.


To study natural history . 2 . of the disease


3. To study the geographical distribution of the disease and environmental effects on disease distribution and compare it to other disease.


To correlate disease with its factors. 4 in trying to identify causative factors (e.g:burket’s lymphoma and malaria burket’s lymphoma is related to EBV and malaria. The link between malaria and EBV is that the aprovirus is transmitted by mosquito, so malaria may be an indicator of an environmental factor


To study & identify risk factors. 5 and causes of the disease in order to prevent occurrence e.g: MI is related to atherosclerosis of coronary vessels, which is related to polysaturated fatty )acids (animal fat


For health planning. . 6 epidemiology provides data related to disease distribution .and its frequency


In evaluation of control. 7 Programs ( by measuring incidence , prevalence and frequency of the disease) especially – if the program is .purely preventive


To study the disease using. 8 analytical and descriptive studies ( so, to identify ) . determinants of the disease


To study disease distribution . 9 And general hypothesis:e.g:- Age distribution of lymphomas when studied shows two peaks (double peaks – or ) BIMODAL - CURVE



Introduction of epidemiology