Update: COVID-19 is now officially classified as a pandemic, the World Health Organization announced Wednesday during a press conference.
"This is the first pandemic caused by coronavirus," said WHO Director-General Tedros Adhanom Ghebreyesus, MD.
"In the past two weeks, the number of cases of COVID-19 outside China has increased 13-fold, and the number of affected countries has tripled," Dr. Tedros said.
"In the days and weeks ahead, we expect to see the number of cases, the number of deaths, and the number of affected countries climb even higher," he continued.
It hasn't — yet. That's why as of now, COVID-19 (the official name for this outbreak) hasn't been categorized as a pandemic. It's still an epidemic. That all may seem like semantics, but there's a very important distinction between the two terms.
What is a pandemic?
A pandemic is defined as the worldwide spread of a new disease, according to the World Health Organization. The word is often used when talking about the flu; an influenza pandemic occurs when "a new influenza virus emerges and spreads around the world, and most people do not have immunity," the WHO says. An influenza pandemic, then, is different from a recurrence of the seasonal flu.
Past pandemics have typically originated from animal influenza viruses, the organization states. The most recent pandemic we've experienced was the H1N1 virus, more commonly known as swine flu, back in 2009.
What's the difference between an epidemic and a pandemic?
The U.S. Centers for Disease Control and Prevention says that an epidemic is "an increase, often sudden, in the number of cases of a disease above what is normally expected in that population in that area." Right now, the COVID-19 outbreak is classified as an epidemic.
Another way to think about it is that a pandemic is "an epidemic that has spread over several countries or continents, affecting a large number of people," the CDC says.
Why is the coronavirus not a pandemic?
The missing factor that's keeping coronavirus from being classified as a pandemic is location. "For the moment, we are not witnessing the uncontained global spread of this virus, and we are not witnessing large-scale, severe disease or death," Tedros Adhanom Ghebreyesus, director general of the WHO, said in a news conference on February 24, according to USA Today. "Does this virus have pandemic potential? Absolutely. Are we there yet? From our assessment, not yet."
In China, there have been over 77,000 confirmed cases of coronavirus with 2,666 deaths as of February 24, according to the WHO. Outside of China, though, those numbers are much smaller. In other countries — including Japan and Italy — there have been 2,459 confirmed cases and 34 deaths.
If coronavirus is declared a pandemic, what should we do?
"We don’t wish to induce panic food or petrol stockpiling, when for 95% of the population, this will be a mild cold," said McMillan, according to The Guardian.
But, he said, some extra precautions will be necessary. "This includes preparing our hospitals for a large influx of patients, stockpiling any antivirals, and advising the public that when the time comes, they will need to think about things like staying at home if ill, social distancing, avoiding large gatherings, etc," McMillan said.
When was the last global pandemic?
The last time the World Health Organization declared a global pandemic was back in 2009 during the H1N1 outbreak, also known as swine flu. Researchers from the Center for Infectious Disease Research and Policy at the University of Minnesota estimated that around 24% of the world's population was infected.
The CDC estimates that 151,700 to 575,400 people around the world died from the H1N1 virus in the first year that it circulated the globe.
How close are we to a pandemic?
It's impossible to say for sure. Right now, the bulk of the infections are located in China. To become a pandemic, the virus would have to break out in different countries and more parts of the world. We hope it doesn't progress that far.
But according to experts affiliated with the CDC, it's very possible that coronavirus's reach will continue to expand. “We expect we will see community spread in [the U.S.],” said Nancy Messonnier, director of the National Center for Immunization and Respiratory Diseases at the CDC, according to the Wall Street Journal. “It’s more of a question of when.”
Anne Schuchat, principal deputy director of the CDC, echoed that statement in a new report. "Current global circumstances suggest it’s likely this virus will cause a pandemic," Schuchat said, according to CNBC. "It’s not so much a question of if this will happen any more, but rather more a question of when this will happen and how many people in this country will become infected and how many of those will develop severe or more complicated disease," she added.