Here's How COVID-19 Compares to Past Outbreaks

SARS, the 1918 flu pandemic, and Ebola have all helped public health officials prepare for major outbreaks.
Each major outbreak is different though, and experts have a hard time predicting how they will end.
The fallout of each disease largely depends on other circumstances — when we catch it, how contagious and fatal it is, how hygienic people are, and how quickly a vaccine or cure becomes available.

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With new cases of the new coronavirus disease, COVID-19, growing day by day, it’s natural to compare the new disease to other outbreaks in recent history.

There was the 1918 influenza, for example, that infected nearly a thirdTrusted Source of the world’s population before it fizzled out.

Then came other threatening viruses that appeared out of nowhere: severe acute respiratory syndrome (SARS), the H1N1 influenza in 2009, and Ebola.

Eventually, we got a handle on all of them.

But the fallout of each disease largely depends on other circumstances — when we catch it, how contagious and fatal it is, how hygienic people are, and how quickly a vaccine or cure becomes available.

The death rate isn’t the only determining factor regarding how devastating and deadly a pandemic will be, according to Dr. Christine Kreuder Johnson, a UC Davis professor of epidemiology and ecosystem health and researcher on USAID’s Emerging Pandemic Threats PREDICT project.

Here, we’ll take a look at how COVID-19 stacks up to other major outbreaks so far:

1918 influenza

The 1918 Spanish flu epidemic was the deadliest flu season we know of, infecting about one-third of the world’s population.

“The 1918 pandemic strain of influenza was new and novel for most people under the age of 40 or 50, but that’s where the death rate really was high — that’s different than the usual flu,” saidDr. Mark Schleiss, a pediatric infectious disease specialist with the University of Minnesota.

Back then, scientists didn’t know viruses caused disease, and we didn’t yet have a vaccine or antivirals to help prevent or treat influenza, nor did we have antibiotics to treat secondary bacterial infections.

Life was also very different back then — for one, we were in the middle of a war and soldiers carried the virus with them all over the world. People were also living in very crowded conditions and had extremely poor hygiene — this helped the disease build and build, according to Johnson.

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