Coronavirus, COVID-19: What's the Actual Definition of Pandemic?

The world is experiencing major anxiety over the coronavirus (COVID-19), with the World Health Organization stating Wednesday that the virus has been categorized as a pandemic. However, many may not be aware of what defines an official "pandemic." According to the WHO, "A pandemic is the worldwide spread of a new disease."

The WHO continued: "An influenza pandemic occurs when a new influenza virus emerges and spreads around the world, and most people do not have immunity. Viruses that have caused past pandemics typically originated from animal influenza viruses."

Elaborating further, the WHO stated, "Some aspects of influenza pandemics can appear similar to seasonal influenza while other characteristics may be quite different. For example, both seasonal and pandemic influenza can cause infections in all age groups, and most cases will result in self-limited illness in which the person recovers fully without treatment.

"However, typical seasonal influenza causes most of its deaths among the elderly while other severe cases occur most commonly in people with a variety of medical conditions."

The WHO later added: "For both seasonal and pandemic influenza, the total number of people who get severely ill can vary. However, the impact or severity tends to be higher in pandemics in part because of the much larger number of people in the population who lack pre-existing immunity to the new virus. When a large portion of the population is infected, even if the proportion of those infected that go on to develop severe disease is small, the total number of severe cases can be quite large."

On Wednesday, the World Health Organization declared coronavirus to be a global pandemic, with the organization's Director-General Tedros Adhanom Ghebreyesus saying, "Pandemic is not a word to use lightly or carelessly. It is a word that, if misused, can cause unreasonable fear, or unjustified acceptance that the fight is over, leading to unnecessary suffering and death."

He continued: "Describing the situation as a pandemic does not change WHO's assessment of the threat posed by this #coronavirus. It doesn't change what WHO is doing, and it doesn't change what countries should do."

Ghebreyesus later stated, "81 countries have not reported any #COVID19 cases, and 57 countries have reported 10 cases or less. We cannot say this loudly enough, or clearly enough, or often enough: all countries can still change the course of this pandemic."


Medical professionals are strongly urging citizens to avoid large gatherings, and to regularly wash their hands, in an effort to limit the virus' reach.

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