18. Define Epidemiology .What is the aims of epidemiology?
Ans: ”The study of the distribution and determinations of health-related states or event in specified populations, and the application of this study to the control of health problems
            Aims/ Objective of Epidemiology:
According to the international Epidemiological Association (IEA), epidemiology has 3 main arms.
            (a) To describe the distribution and size of disease problems in human populations.
            (b) To identify etiological factors in the pathogenesis of disease.
            (c) To provide the data essential to the planning, implementation and evaluation of service for the prevention, control and treatment of disease and to the setting up priorities among those services.
            * The ultimate aim of epidemiology is to lead effective action:
            (a) To eliminate or reduce the health problem or its consequence
            (b) To promote the health and well-being of society as a whole by preventing its consequence   in future.
19. Discuss the use of epidemiology?
Ans: Study of the distribution and determination of disease in a defined population helps to:
            1. Identify factors that cause disease.
            2. Identify factors or conditions that can be used or modified to preventive the occurrence or spread of disease.
            3. Explain how an why disease and epidemics occur.
            4. Evaluate the effectiveness of vaccines and different forms of therapy.
            5. Establish a clinical diagnosis of disease.
            6. Identify the health needs of the community.
            7. Evaluate the effectiveness of health programmers.
            8. Predict the future health needs of a population.