Answer:

The importance of surveillance in Epidemiology:

The World Health Organization (WHO) defines public health surveillance as the “continuous, systematic collection, analysis and interpretation of health-related data needed for the planning, implementation, and evaluation of public health practice.

A health problem must be well defined before it can be solved. Surveillance systems generate data that help public health officials understand existing and emerging infectious and non-infectious diseases. Without a proper understanding of the health problem, it will be difficult to ameliorate the health issue.

The main types of information collected by surveillance systems to measure the relative importance of a disease are:

• Incidence/prevalence
• Severity (case fatality rate)
• Mortality rate
• Productivity loss
• Premature mortality (YPLL)
• Costs in medical care
• Preventability of disease