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On the verge of a pandemic, can the world look to China for answers?

The COVID-19 could become a pandemic — an unsettling and often misunderstood term. New data shows a possible but challenging path to containment.

The coronavirus COVID-19 is now a pandemic, so what now?
A previous version of this video incorrectly stated how many people the 1918 Spanish influenza killed.
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New coronavirus infections are rising around the world, but fewer of those new infections are in China, where the COVID-19 originated. 

China's massive containment effort appears to be succeeding, based on data recently released by the Chinese Center for Disease Control and Prevention. 

According to the CCDCP data, diagnosed cases of COVID-19 peaked at more than 3,500 daily cases in China — about two weeks after China shutdown Wuhan, where this strain of coronavirus arose. 

The data represents almost half of the known infections worldwide and reveals an intriguing pattern. 

Can such efforts in other countries avert a pandemic? Global health officials are skeptical that other governments can quarantine large parts of their countries as effectively as the itarian Chinese.

Dennis Carroll, former director of the U.S. Agency for International Development's Global Health Security and Development Unit, credited China's "extraordinary control measures" with delaying the spread of the virus, but he said avoiding a pandemic is "very unlikely."

COVID-19 has killed more than a 2,000 people and sickened tens of thousands on five continents, but it's not yet a pandemic according to the World Health Organization. WHO has been careful about using "pandemic" because of some grave associations with the word.

“What we see is epidemics in different parts of the world," said Dr. Tedros Adhanom Ghebreyesus, WHO director-general, during a conference call Monday about COVID-19.

Four terms (endemic, outbreak, epidemic and pandemic) are important to understand how diseases emerge and affect populations, according to the Journal of the American Medical Association:

Endemic

An endemic disease affects a group of people at "a fairly stable predictable rate." The illness could affect an area as small as a town or as large as a continent, but it emerges in a way that doctors and researchers expect. 

Outbreak

An outbreak is a greater-than-anticipated increase in the number of endemic cases. It can also be a single case in a new area.

Epidemic

An outbreak that spreads over a larger geographical area is considered an epidemic. Tedros said the recent boom in COVID-19 cases in Italy, South Korea and Iran was "certainly very concerning." 

But the new coronavirus is not yet considered a pandemic, despite its spread to multiple countries.

Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, told USA TODAY there are several reasons for this:

  • The virus' spread in other countries has not yet been sustained for a significant amount of time.
  • Less than 4% of COVID-19 cases are outside China and are related to travel, so the global impact isn’t yet considered widespread.

Pandemic

In the minds of many, the word "pandemic" is closely connected to the 1918 flu pandemic that killed tens of millions of people, Fauci said.

But by definition, a pandemic doesn't require that scale of destruction; it's more a term of how widespread an illness is than how lethal it is.

When a strain of H1N1 flu became a pandemic in 2009, it killed more than 12,000 and sickened over 60 million Americans in one year. But now, it circles the globe as a seasonal virus that causes limited health concerns. 

"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 said Monday. "Does this virus have pandemic potential? Absolutely. Are we there yet? From our assessment not yet."

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