In the spring of 1918, just as the man-made horrors of World War I were finally starting to wind down, Mother Nature unleashed the deadliest strain of influenza in modern history. The virus infected as much as 40 percent of the global population over the next 18 months. Of these, an estimated 20 to 50 million perished—more than the roughly 17 million people killed during the First World War. The pandemic’s grasp stretched from the United States and Europe to the remote reaches of Greenland and the Pacific islands. Its victims included the likes of President Woodrow Wilson, who contracted it while negotiating the Treaty of Versailles in early 1919.
As the pandemic reached epic proportions in the fall of 1918, it became commonly known as the “Spanish Flu” or the “Spanish Lady” in the United States and Europe. Many assumed this was because the sickness had originated on the Iberian Peninsula, but the nickname was actually the result of a widespread misunderstanding.
Spain was one of only a few major European countries to remain neutral during World War I. Unlike in the Allied and Central Powers nations, where wartime censors suppressed news of the flu to avoid affecting morale, the Spanish media was free to report on it in gory detail. News of the sickness first made headlines in Madrid in late-May 1918, and coverage only increased after the Spanish King Alfonso XIII came down with a nasty case a week later. Since nations undergoing a media blackout could only read in depth accounts from Spanish news sources, they naturally assumed that the country was the pandemic’s ground zero. The Spanish, meanwhile, believed the virus had spread to them from France, so they took to calling it the “French Flu.”
While it’s unlikely that the “Spanish Flu” originated in Spain, scientists are still unsure of its source. France, China and Britain have all been suggested as the potential birthplace of the virus, as has the United States, where the first known case was reported at a military base in Kansas on March 11, 1918. Researchers have also conducted extensive studies on the remains of victims of the pandemic, but they have yet to discover why the strain that ravaged the world in 1918 was so lethal.
Though it had been around for ages, leprosy grew into a pandemic in Europe in the Middle Ages. A slow-developing bacterial disease that causes sores and deformities, leprosy was believed to be a punishment from God that ran in families.
The Black Death haunts the world as the worst-case scenario for the speed of disease's spread. It was the second pandemic caused by the bubonic plague, and ravaged Earth’s population. Called the Great Mortality as it caused its devastation, it became known as the Black Death in the late 17th Century.Read more: Social Distancing and Quarantine Were Used in Medieval Times to Fight the Black Death
In another devastating appearance, the bubonic plague led to the deaths of 20 percent of London’s population. The worst of the outbreak tapered off in the fall of 1666, around the same time as another destructive event—the Great Fire of London. Read more: When London Faced a Pandemic—And a Devastating Fire
The first of seven cholera pandemics over the next 150 years, this wave of the small intestine infection originated in Russia, where one million people died. Spreading through feces-infected water and food, the bacterium was passed along to British soldiers who brought it to India where millions more died. Read more: How 5 of History's Worst Pandemics Finally Ended
The first significant flu pandemic started in Siberia and Kazakhstan, traveled to Moscow, and made its way into Finland and then Poland, where it moved into the rest of Europe. By the end of 1890, 360,000 had died.Read more: The Russian Flu of 1889: The Deadly Pandemic Few Americans Took Seriously
The avian-borne flu that resulted in 50 million deaths worldwide, the 1918 flu was first observed in Europe, the United States and parts of Asia before spreading around the world. At the time, there were no effective drugs or vaccines to treat this killer flu strain. Read more: How U.S. Cities Tried to Halt the Spread of the 1918 Spanish Flu
Starting in Hong Kong and spreading throughout China and then into the United States, the Asian flu became widespread in England where, over six months, 14,000 people died. A second wave followed in early 1958, causing about 1.1 million deaths globally, with 116,000 deaths in the United States alone.Read more: How the 1957 Flu Pandemic Was Stopped Early in Its Path
First identified in 1981, AIDS destroys a person’s immune system, resulting in eventual death by diseases that the body would usually fight off. AIDS was first observed in American gay communities but is believed to have developed from a chimpanzee virus from West Africa in the 1920s. Treatments have been developed to slow the progress of the disease, but 35 million people have died of AIDS since its discoveryRead more: The History of AIDS
First identified in 2003, Severe Acute Respiratory Syndrome is believed to have started with bats, spread to cats and then to humans in China, followed by 26 other countries, infecting 8,096 people, with 774 deaths.Read more: SARS Pandemic: How the Virus Spread Around the World in 2003
COVID-19 is caused by a novel coronavirus, the family of viruses that includes the common flu and SARS. The first reported case in China appeared in November 2019, in the Hubei Province. Without a vaccine available, the virus has spread to more than 163 countries. By March 27, 2020, nearly 24,000 people had died.Read more: 12 Times People Confronted a Crisis With Kindness