Wondering, pandemic vs. epidemic, what’s the difference? These two terms are often used similarly, even among experts. Both pandemic and epidemic may be used to refer to the rapid spread of an infectious disease; and both terms may be used in reference to the sameillness at different points of its development. What is the difference between an epidemic and a pandemic? It’s a matter of scale: a pandemic may affect countries while an epidemic has spread throughout a community or region.
As the western world confronts its first pandemic in over 100 years, the coronavirus, we’re left wondering about the differences between an epidemic vs pandemic, and asking what we can learn from the past. What was the worst one in history? And what can we do differently?
As always, the following is not medical advice. If you have questions about your health or COVID-19, please speak with your physician. Additionally, please see the CDC website for current information on the evolution of the coronavirus.
Typically the definition of a pandemic is an outbreak of an infectious disease that affects a large portion of the population across a large geographic area, usually different countries.
Keep in mind that the severity of a disease does not affect whether or not it is defined as a pandemic.
For example, Ebola, which has a fatality rate of approximately 50% according to the WHO, was considered an epidemic between 2013 and 2016 specific to Western Africa. At the time of writing, there is an Ebola outbreak in the Congo. In neither case is it considered a pandemic.
On March 11, 2020, the World Health Organization (WHO) classified SARS-CoV-2, also known as the coronavirus or COVID-19, as a pandemic. Before that, it was considered an epidemic. So, what’s the difference?
The difference comes down to the rate of spread and regions affected. When the virus had officially spread across different countries and infections were consistently and clearly increasing globally, its status changed.
The World Health Organization (WHO) is responsible for making that call. The WHO is an agency within the United Nations responsible for safeguarding global health.
There are several classifications for a disease determined by the WHO. These classifications determine what health organizations can do to fight a specific disease. It affects things like funding and alerts individuals and governments that an illness is to be taken seriously.
For instance, it tells governments that community spread — contagion without known contact with an infected person — is likely. Additionally, it tells governments to start preparing hospitals for an influx of pandemic-related patients.
A disease cannot be immediately classified as a pandemic. According to the WHO, a disease’s spread may be classified into six phases:
An endemic disease is specific to a region and not spreading at the same rate as an epidemic or a pandemic. An epidemic covers a large region and is considered more out of control. A pandemic is on a global scale.
For example, Hepatitis B (HBV) and malaria may be considered endemic in certain parts of the world.
The next step between endemic and epidemic is outbreak. An outbreak may turn into an epidemic if not controlled. It may also refer to the spread of a disease to a region in which it is not endemic.
Coronavirus is far from the first pandemic or epidemic. In many cases, it may be tough to identity the differences between the two because ancient cultures did not use the same language — or have the same preventative measures — as we now do. In many cases, they were referred to as plagues.
Here are a few examples of pandemics throughout history:
The Black Death is considered one of the worst pandemics in history, having killed 30 million people in approximately 6 years. The Spanish Flu is considered the worst in modern times, resulting in the deaths of between 20–40 million people. Due to the lack of accurate data for many of the world’s epidemics, it is challenged to determine which had the highest death count and rate of infection.
Yes, the World Health Organization has classified COVID-19 as such, as of March 11, 2020.
The coronavirus is officially classified as a pandemic, meaning that it has spread globally and has a high infection rate. It is far from the first of its kind, however: History has been dotted with infectious disease breakouts, some with higher impact than others.
The above information is meant for educational purposes. It is not medical advice.