As the COVID-19 death toll climbed Friday, April 17, the coronavirus first reported by Chinese doctors in December 2019 has surpassed yellow fever on the list of deadliest pandemics.

To date, more than 2.2 million confirmed cases of COVID-19 have been reported worldwide, though the actual number is suspected to be much higher due to underreporting and asymptomatic carriers of the virus.

It's been detected in nearly every country, and COVID-19, the respiratory disease caused by coronavirus, has killed more than 150,000 people to date.

The rapid rate of transmission has prompted countries to lock down travel and borders, cripple the economy, force businesses and schools to close and overload health care systems.

Yellow fever was first detected in the 1800s, and mostly found in subtropical areas of Africa and South America. The virus is spread to people by the bite of an infected mosquito, and can cause aches and pains to severe liver disease with bleeding and yellowing skin, according to the Centers for Disease Control and Prevention. It is a a rare cause of illness for U.S. travelers, the CDC reports.

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As COVID-19 infections quickly spread globally, experts warn people to practice "social distancing," or remaining at least 6 feet away from others, in an attempt to "flatten the curve." These phrases quickly have become part of a new lexicon for most people.

For centuries, virus outbreaks have swept across the globe, killing millions of people. Here is a look at the world's most deadly pandemics.