Epidemiology –Topic 1 DQ 1-Define endemic, epidemic, and pandemic, and provide an example of each.

Epidemiology –Topic 1 DQ 1-Define endemic, epidemic, and pandemic, and provide an example of each.

Define endemic, epidemic, and pandemic, and provide an example of each. Describe a current epidemic. Describe one example of each of the prevention types (primary, secondary, and tertiary) that could be applied to control the epidemic.





The amount of a given disease that is normally present in a given community is referred to as the baseline level or the endemic level of the disease. The baseline level of disease is, therefore, not ideally the desired level but the observable level. However, while some diseases might be rare in given populations and communities, any occurrence of cases can warrant an epidemiologic investigation such as plague, rabies, and polio (Fre´rot et al., 2018). Other diseases may occur more frequently in a given population with only significant deviations warranting an investigation. Endemic refers to the usual prevalence or constant presence of a disease or infectious agent in a given population within a certain geographic area (Fre´rot et al., 2018). On the other hand, an epidemic refers to a disease affecting a significant number of people in a given region, population, or community. During an epidemic, a sudden increase in the number of cases of a given disease above what is normally expected is therefore witnessed in a given geographic region, population, or community. On the other hand, a pandemic is an epidemic that spreads over different geographic regions and continents. Pandemics usually affect significant numbers of people (Fre´rot et al., 2018).

Description of a Current Epidemic

One of the current epidemics is the HIV /AIDS epidemic.  Although many countries, especially developed countries, have been able to control HIV /AIDS, the disease still remains to be a significant global public health challenge. By 2020 approximately 37.6 million people around the world had HIV, with is at least 1.5 million infections occurring worldwide. HIV /AIDS disproportionately affects developing countries, especially in sub-Saharan Africa (Dehne et al., 2016).


Prevention Types

The primary prevention strategies that can be adapted to control the HIV epidemic include abstaining from sex or having one HIV-negative monogamous partner. The use of latex condoms and having sex is also an important primary prevention approach for the HIV epidemic. The secondary prevention strategies for the HIV epidemic include getting tested and the use of pre-exposure prophylaxis. On the other hand, the tertiary prevention approaches for HIV include the use of antiretroviral therapy to improve the quality of life of patients already infected with the virus (Dehne et al., 2016).



Dehne, K. L., Dallabetta, G., Wilson, D., Garnett, G. P., Laga, M., Benomar, E., Fakoya, A., Baggaley, R. C., Nelson, L. J., Kasedde, S., Bermejo, A., Warren, M., & Benedikt, C. (2016). HIV Prevention 2020: a framework for delivery and a call for action. The Lancet HIV, 3(7), e323–e332. https://doi.org/10.1016/s2352-3018(16)30035-2

Fre´rot M, Lefebvre A, Aho S, Callier P, Astruc K, & Aho Gle´le´ LS (2018). What is

epidemiology? Changing definitions of epidemiology 1978-2017. PLoS ONE 13(12): e0208442. https://doi.org/10.1371/journal. pone.0208442