Epidemiology

• Epidemiology

• Definition and Natural History





• Epidemiology is the study of how disease is distributed in populations and factors that
• influence or determine this distribution.

• Epidemiology is the study of the distribution and determinants of health related states

• Objectives of Epidemiology:

• First. To identify the etiology or cause of a disease and the relevant risk factors i.e. factors that increase a person’s risk for a
disease

• Second. To determine the extent of disease

• found in the community

• Third. To study the natural history and

• prognosis of disease

• Fourth. To evaluate both existing and newly developed preventive and therapeutic

measures and modes of health care
delivery

• Fifth. To provide the foundation for developing public policy relating to

• environmental problems, genetic issues, and other considerations regarding disease prevention and health promotion

Types of prevention

Primary prevention
Prevention the initial
immunization

development of

disease

Secondary prevention

Early detecting of
Screening for cancer


existing disease to

reduce severity and

complications

Tertiary prevention

Reducing the impact
Rehabilitation for

of disease

stroke

• THE COMPONENTS OF COMMUNICABLE DISEASES

• -INFECTIOUS AGENTS
• HUMAN RESERVOIR
• ANIMAL RESERVOIR NON-LIVING RESERVOIR

• *THE SOURCE OF INFECTION

• -ROUTE OF TRANSMISSION


• -HOST FACTORS
• Non-specific resistance
• Specific resistance
• Genetic Factors
• Acquired factors
• Factors affecting host immunity
• Age
• Sex
• Pregnancy
• Nutrition
• Trauma and fatigue

aprogram for the control of acd ESTABLISHIN

RECOGNITION OF INFECTION
• NOTIFICATION OF DISEASES
• IDENTIFICATION OF THE SOURCE OF INFECTION

*The dynamic of infection

• ASSESMENT OF THE EXTENT OF OUTBREAK


• METHODS OF CONTROL
• Objectives :
• ELIMINATION OF THE RESERVOIR
• Human reservoir
• -Isolation of patients
• -quarantine
• The zoonoses
• Non-living reservoir

• INTERRUPTION OF TRANSMISSION

• PROTECTION OF THE SUSCEPTIBLE HOST
• -Passive immunization
• - Active immunization
Strategies for using active immunization
• -routine childhood immunization
• -epidemic control New vaccines

• STRATEGIES for the use of drugs in the control of communicable diseases

• mass chemotherapy
• selective population chemotherapy
• targeted chemotherapy
• DRUG SPECIFICATION
• Efficacy
• Safety
• Simple regimens
• Acceptable
• Affordable


• ANTIMICROBIAL RESISTANCE
• overuse and misuse
• poor compliance
• self-medication
• counterfeit drugs
• poor control in hospitals poor standards of hygiene –
• international travel and trade