Epidemic vs. pandemic? Isolation vs. quarantine? Let us explain.

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In just a matter of weeks, the entire world has had to master the coronavirus lexicon.

From isolation to social distancing, epidemic vs. pandemic, and even just learning what COVID-19 stands for, we’ve all been taken back to school.

If you’re confused, don’t worry. You’re not alone, and we’ve got your back. Here are all the terms you should know during the coronavirus pandemic so you can feel a bit more knowledgeable and prepared for whatever the future holds.


Despite the fact that it seemed to come out of nowhere, the term coronavirus is nothing new. Coronavirus actually refers to a “large family of viruses that cause illness ranging from the common cold to more severe diseases such as Middle East Respiratory Syndrome (MERS-CoV) and Severe Acute Respiratory Syndrome (SARS-CoV),” according to the World Health Organization (WHO).

The organization added, coronaviruses are “zoonotic,” which means they are transmitted between animals and people. SARS-CoV, it said, was transmitted from civet cats to humans, while MERS-CoV came from dromedary camels.

Why the name? Dictionary.com explained, “When looked at under a microscope, coronaviruses appear to be surrounded by a spiky array thought to look like a corona, or a crown-like shape, hence the name coronavirus.


COVID-19 is the name of the "infectious disease caused by the most recently discovered coronavirus," according to WHO. Its short-handed name comes from the fact that it was first discovered in Wuhan, China in December 2019, thus COVID-19. The technical name of the virus that caused COVID-19 is severe acute respiratory syndrome coronavirus 2, or SARS-CoV-2.


According to Dictionary.com, “an epidemic is a temporary prevalence of a disease spreading from person to person in a locality where that disease is not permanently prevalent.” In other words, an epidemic occurs when a disease moves past its usual borders and infection rates skyrocket in different locations. Other epidemics include the Zika epidemic of 2017 and the Ebola epidemic between 2014 and 2016.


In March, WHO deemed the coronavirus a global pandemic, giving it a whole new classification. A pandemic, Dictionary.com explained, is “a disease prevalent throughout an entire country, continent, or the whole world. A pandemic is an epidemic that has spread over a large area.”

WHO specifically uses the term when a new disease that people have no immunity for breaks out and spreads across multiple countries at the same time. You can learn more about the organization’s pandemic phases here.

Flatten the curve

The term “flatten the curve” has become an internet favorite during the coronavirus outbreak. As LiveScience explained, it “refers to the projected number of people who will contract COVID-19 over a period of time.” The curve of the number of people infected with the virus could skyrocket to a peak with no intervention, or remain shorter and longer, hence “flattening the curve.” Medical experts are hoping via interventions such as hand washing, limiting social gatherings, and isolating sick populations, we can “flatten the curve” so we do not overwhelm our nation’s medical systems.


As the spread of the coronavirus continues, local, federal, and global government officials are asking people to take on various levels of distancing. The first is isolation. According to the Department of Health and Human Services (HSS), isolation is used to “separate ill persons who have a communicable disease from those who are healthy. Isolation restricts the movement of ill persons to help stop the spread of certain diseases. For example, hospitals use isolation for patients with infectious tuberculosis.”

This means if you are ill with the coronavirus you are asked to isolate from any other people and are asked to not leave a specific space.


During this time many people are doing what is known as self-isolation. The major difference here is this is completely voluntary isolation. It could be because a person believes they are ill or wants to reduce their risk of catching a virus.


Quarantine is used by the HSS to “separate and restrict the movement of well persons who may have been exposed to a communicable disease to see if they become ill. These people may have been exposed to a disease and do not know it, or they may have the disease but do not show symptoms. Quarantine can also help limit the spread of communicable disease.”

For example, if you just returned from a trip overseas you will be asked to quarantine for 14 days to ensure you are not infectious to others.


Like self-isolation, self-quarantine is completely voluntary.

Shelter in Place

Several counties in California, including the city of San Francisco, were asked to shelter in place for several weeks to stop the spread of coronavirus. What does this mean? Essentially, it means to not leave your house — at all — unless absolutely necessary. Those necessary activities, according to a city-wide ordinance, only include going to the grocery store, seeking medical attention, getting medicine, and taking a pet to the vet for an emergency.

“Widespread testing for COVID-19 is not yet available but is expected to increase in the coming days,” the mandate explained. “This order is necessary to slow the rate of spread.”

Safer at Home

In late March, the city of Los Angeles announced its own term, safer at home. This term and its mandates are a bit less strict than shelter in place, however, Mayor Eric Garcetti explained that “safer at home” is in the same spirit as shelter in place.

“We are all safer at home. Staying in our residences, being aggressive about hygiene, and practicing safe social distancing are the most effective ways to protect ourselves, the people we love, and everyone in our community,” Garcetti said. “Each one of us is a first-responder in this crisis, and Angelenos understand that we have to make big sacrifices right now to save lives. This isn’t forever — and we’ll get through it together.”

This means you can still go to the grocery store, take a walk, work out outside, and go to a restaurant for takeout. However, you cannot visit friends and family if there is no urgent need or visit loved ones in the hospital, and you must maintain a six-foot distance from others.

Social distancing

Last, but most certainly not least, is the term social distancing. According to Johns Hopkins, social distancing means canceling plans, closing schools, working from home, and postponing any large gathering.

“While it may be disappointing to hear that so many sports events, cruises, festivals and other gatherings are being canceled, there is a public health reason for these measures,” the experts at Johns Hopkins wrote. “These cancelations help stop or slow down the spread of disease allowing the health care system to more readily care for patients over time."

And, even if you do go out in the world, the Centers for Disease Control and Prevention (CDC) once again wants you to maintain a six-foot gap between you and anybody else. Because your life, or the life of someone you love, may depend on it.