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Outbreaks, Epidemics and Pandemics

Outbreaks, epidemics and pandemics and their impact on human populations.

The amount of disease that is normally present in a population within a geographical area is referred to as the endemic level of disease. When disease starts to spread, outbreaks, epidemics and pandemics can occur, all of which can have significant social and economic impact on human populations.

These terms, although often easily confused, have very different meanings. The US Centre for Disease Control defines these terms as follows:

Epidemic: An increase, often sudden, in the number of cases of a disease above what is normally expected in that population in that area.

Outbreak: Carries the same definition of epidemic, but is often used for a more limited geographic area.

Pandemic: An epidemic that has spread over several countries or continents, usually affecting a large number of people.


Did you know that most epidemics and pandemics are caused by viruses? Viruses, such as measles, influenza and HIV are the most common causes of epidemics. Epidemics, outbreaks and pandemics can all have significant social and economic impacts on human populations. 

Here’s an example of the social impact of disease: 

  • According to the WHO, since the beginning of the HIV/AIDS epidemic, about 35 million people worldwide have died of HIV.  

Here are examples of the economic impact of disease:

  • According to the Canadian Healthcare Influenza Immunization Network, about 1.5 million workdays are lost in Canada every year because of the flu, resulting in healthcare costs and lost productivity equalling $1 billion.
  • In 2003, following an outbreak of Severe Acute Respiratory Syndrome (SARS), there was a decrease in tourism in Hong Kong and other areas of SouthEast Asia. The SARS outbreak started in Hong Kong, and as a result the tourism industry plummeted there. Hotels, restaurants, tour operators and almost every aspect of Hong Kong’s economy suffered from the loss of tourist spending.

Browse the interactive map below from Vaccineswork.org (this website is run by Gavi, the Vaccine Alliance). You can track outbreaks of vaccine-preventable diseases like measles and whooping cough around the globe today.

Watch the video below to learn more about Outbreaks, Epidemics, and Pandemics.

All lessons & quizzes are free!

 This was just one of the lessons in our Outbreaks section. There are over 60 lessons on Kids Boost Immunity just like this one on a variety of subjects. Each lesson includes a quiz, and every time a student scores 80% or higher on a quiz, we will donate life-saving vaccines to UNICEF Canada. Sign up now!

To see other sample lessons, click here.

Last modified: 
Oct 28, 2019