Tell Me More: Epidemic, Endemic, and Pandemic, what do they really mean?

Throughout the COVID-19 pandemic, certain scientific terms have been at the forefront of news coverage and have subsequently become part of our everyday vernacular. Though we have now become accustomed to words like endemic, epidemic, and pandemic, understanding their true meaning can be more complicated.

Below we break down what each term means.

Endemic
An endemic disease is one that is consistently present throughout a specific region or population. The prevalence of the disease remains stable and its spread is fairly predictable over time.

Epidemic
An epidemic occurs when a disease, specific health-related behavior, or other health-related event spreads unexpectedly or quickly across a specific geographical area or population. It can occur if an endemic disease suddenly becomes more prevalent, or if a new disease begins to affect a region or specific population.

Pandemic
A pandemic occurs when a disease spreads across countries or continents at a fast rate with new cases appearing every day. Pandemics have become more likely in recent years due to increased international travel. Increased urbanization also means that many people live in densely populated towns and cities, which can increase rapid transmission of viruses and disease.

Over time, a disease can move from one of these classifications to another (i.e., from epidemic to pandemic, or vice-versa).

It’s important to note that these terms don’t describe the severity of a disease, but rather its prevalence.