[01] Abdulhadi Sale Kumurya, Department of Medical Laboratory Science, Faculty of Allied Health Sciences, Bayero University, Kano, Nigeria. [02] Sadiya Ashiru Auta, Department of Biochemistry, Faculty of Basic Medical Sciences, Bayero University, Kano, Nigeria.

Incidence and prevalence are the dominant rates in epidemiology, distinguishable by their respective foci. In other words, incidence is concerned solely with new events, while prevalence considers both new and old cases. These measures are used to produce a number of views on health and disease. Incidence should not be confused with prevalence, which is the proportion of cases in the population at a given time rather than rate of occurrence of new cases. Thus, incidence conveys information about the risk of contracting the disease, whereas prevalence indicates how widespread the disease is. Prevalence is the proportion of the total number of cases to the total population and is more a measure of the burden of the disease on society with no regard to time at risk or when subjects may have been exposed to a possible risk factor. Prevalence can also be measured with respect to a specific subgroup of a population. Incidence is usually more useful than prevalence in understanding the disease etiology: for example, if the incidence rate of a disease in a population increases, then there is a risk factor that promotes the incidence.

Epidemiology, Prevalence, Incidence, Rate

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