In the past two decades, the world battled Ebola, SARS and more than one major flu outbreak. Those left tragedies in their wake but didn’t cause the same level of societal and economic disruption that COVID-19 has. As a result, they can help us understand this new coronavirus.
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SARS and MERS didn’t cause the same level of devastation that COVID-19 has largely because they aren’t as easily transmitted. Rather than moving by casual, person-to-person transmission, SARS and MERS spread from much closer contact, between family members or health care workers and patients.
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[W]hy didn’t the swine flu overwhelm our health care systems and grind our economies to a halt? The main difference is that it ended up being a much milder and less deadly infection. There are a range of estimated case fatality rates for swine flu, but even the highest, less than 0.1 percent, are much lower than the current estimates for COVID-19.…
In each of these cases, the viral outbreak lacked one of the key components that COVID-19 has that allowed it to tip over into a global pandemic. “SARS-CoV-2 is kind of a perfect storm,” said Angela Rasmussen, a virologist at Columbia University who specializes in infectious diseases.
