1 Never use a microwave or conventional oven to pre-heat your flask. 2  If your flask has not been used for some time, rinse with warm water to remove any residual odours.  DO NOT overfill your flask. Leave sufficient space in the neck to fit the stopper.
Prevalence is a measure of disease that allows us to determine a person's likelihood of having a disease. Therefore, the number of prevalent cases is the total number of cases of disease existing in a population.
prevalence rate the number of people in a population who have a disease at a given time; the numerator is the number of existing cases of disease at a specified time and the denominator is the total population.Time may be a point or a defined interval, and is traditionally the former if unspecified.revalence (prevÉlÉns) , adj in epidemiology, all the new and old cases of a disease or occurrence of an event during a particular period. It is expressed as a ratio in which the number of events is the numerator and the population at risk is the denominator.