Prevalence is a -

. the term "disease prevalence refers specifically to all current cases(old and new)existing at a given point in time or over a period of time in a given population.it is the total number of all individuals who have an attribute or disease at a paicular time or during a paicular period divided by the population at risk of having the attribute or disease at this point in time or midway through the period. ref:park&;s textbook of preventive and social medicine,22 nd edition ,pg no 58