The COVID-19 outbreak is now a pandemic. What does that mean?

The World Health Organization on Wednesday declared COVID-19 outbreak a pandemic, citing infections in over 121,000 people worldwide.

But what is a pandemic and how does the upgraded status of the disease affect the way it’s treated or diagnosed?

According to the Centers for Disease Control, a pandemic refers to an epidemic that has spread over several countries or continents, usually affecting a large number of people.

[RELATED: Here’s what we know about the coronavirus cases in Florida]

Until this point, the WHO had categorized the spread of COVID-19 as a series of epidemics and not necessarily a worldwide issue.

The CDC defines an epidemic as an increase, often sudden, in the number of cases of a disease above what is normally expected in that population in that area.

WHO Director General Dr. Tedros Adhanom Ghebreyesus released a statement saying that gaining control of the COVID-19 outbreak is a responsibility that all countries of the world must play a part in.

“We are not at the mercy of this virus,” Ghebreyesus said. “All countries must aim to stop transmission and prevent the spread of COVID-19, whether they face no cases, sporadic cases, clusters or community transmission.”

Even more importantly, Ghebreyesus shared his hopeful stance on the pandemic, saying this would be the first pandemic in history that could be controlled.

“Let hope be the antidote to fear. Let solidarity be the antidote to blame. Let our shared humanity be the antidote to our shared threat," Ghebreyesus said.

Pandemics are not a new phenomena and have been part of human society for centuries, with one of the earliest outbreaks dating back to 1580, which represents the first influenza pandemic.

The CDC reports there were at least four influenza pandemics in the 19th century, with a single outbreak known as the Spanish flu causing over 21 million deaths globally from 1918 to 1919. For perspective, more American soldiers died from the 1918 flu pandemic than were killed in battle during World War I in 1918, according to the CDC.

The most recent pandemic in the world was the H1N1 flu pandemic in 2009, which killed hundreds of thousands globally, according to the CDC.

It’s also important to differentiate the COVID-19 pandemic from a plague, which is a word that often instills fear. The word “plague” itself refers to a contagious bacterial disease characterized by fever and delirium, typically with the formation of buboes, such as in the bubonic plague, and possible infection of the lungs, according to the CDC.

As the plague is a bacterial infection, a course of antibiotics can be used to treat the disease, whereas COVID-19 is a viral infection, rending antibiotics useless as treatment.

Local health officials in Florida announced eight new cases of COVID-19 on Tuesday, bringing the state’s total count to 21. The Florida Department of Health said the new cases include seven Florida residents and a Georgia resident who is currently in Alachua County, Florida.

The latest round of Florida residents who have tested positive live primarily on Florida’s west coast, in Collier, Pinellas and Pasco counties.

The health department said the latest patients include three Collier County residents: two women ages 68 and 64, and a 73-year-old man. Two men, ages 67 and 64, tested positive in Pinellas County. A 46-year-old man in Pasco County, north of Tampa, also tested positive. The other person diagnosed with the virus is a 68-year-old man in Nassau County, which is north of Jacksonville on Florida’s Atlantic Coast.

For most people, the new coronavirus causes only mild or moderate symptoms, but it can cause more severe illness including pneumonia in older adults and people with existing health problems. The vast majority of people recover from the new virus within weeks.

The new patients and the others who’ve tested positive in Florida are self-isolating for 14 days as instructed by the U.S. Centers for Disease Control and Prevention.

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