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.
This isnât very useful, as the larger the number of people in the population, the more people might have the disease, so a prevalence rate (often referred to simply as prevalence) is what we really want to know. \[ Number of cases of disease in given time period/total number in population in that time period \].