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When looking back through human history, one would be hard-pressed to find an era, civilization, or community that has not been impacted by an infectious disease outbreak. From the bubonic plague to influenza to cholera, epidemics and pandemics the world over have come in many shapes, sizes, and death tolls. But sometimes, the death toll alone doesn’t reflect the true, lasting impact that specific infectious disease outbreaks had on the populations they infected - or those nearby.
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Over the last few years, we all got to experience an infectious disease outbreak
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as COVID-19 and its many Kang-like variants spread around the globe. But historically speaking, epidemics, and even pandemics, are not all that uncommon
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Since the moment we existed on Earth, humans have constantly been getting each other sick
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So, today, we're looking back at the most significant infectious diseases of every century
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Basic familiarity with leprosy, though not by name, goes all the way back to the ancient world
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The Bible mentions a number of skin disorders that may have included leprosy, and in the New
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Testament, Jesus famously heals some of the afflicted rather than shunning them. The Hindu
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Vedas, dating all the way back to 2000 BCE, mention skin diseases that likely include leprosy
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and many historians also believe that ancient Greek and Roman references to elephantitis
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actually refer to patients with leprosy symptoms. The widely feared illness became associated
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with gruesome, disfiguring symptoms. But at its core, it's a bacterial infection
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that damages the nerves, respiratory tract, skin, and eyes. Because the nerve damage can result in an inability
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to feel pain in your extremities, it could lead to repeated infections
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or even removal of the limbs. Leprosy really needs a better publicist
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Prolonged exposure is required for the bacteria to jump between humans. Though if the sick person is coughing or leaking a lot of fluid from their nose, that can help
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contribute. This also made it more common in low-income areas, where people lived closer
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together in less hygienic environments. By the 10th century in Europe, leprosy was among the
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most pressing public health issues. In the early Middle Ages, the Roman church began setting aside
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funds for leper colonies and clinics, separating patients from the general population so they could
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be looked after, often by monastic orders. In present-day Belgium alone, it's believed there
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were up to 800 such clinics around the First Crusades. There wasn't much available in the way
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of actual medical treatment for these unfortunate patients. The main goal was not so much curing their disease
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as quarantining the sick to prevent any wider spread. Today, leprosy is typically treated with antibiotics
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So if anyone invented a time machine, now would be a good time to give it to a doctor
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Well, we could just let the antibiotics drive themselves. Influenza was also a serious concern in medieval times
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though we can't be fully certain that every outbreak referred to as the flu at the time actually was
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Many infections with a similar symptom profile were likely floating through the air
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and medieval doctors didn't necessarily associate respiratory illness with the flu Misdiagnoses were extremely likely That being said the first confidently the flu pandemic started around the year 1510 in East Asia before spreading to North
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Africa and Europe. Following this major outbreak, seasonal influenza occurred, with additional
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pandemics in 1557 and 1580. By the close of the 16th century, the disease was far better understood
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but at the cost of mass infection and death. In fact, it's estimated that nearly everyone in the
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impacted area was infected, with a death rate of around 1%. Despite medical advances in understanding
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the disease, flu outbreaks remained a routine problem throughout modern European history
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In 1729, an influenza outbreak spread rapidly across Europe, reached pandemic proportions
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within six months, and ultimately made it to the Americas. An even larger-scale influenza outbreak
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happened in 1781, which is believed to have started in China before spreading around the world
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This one claimed tens of millions of lives and was particularly devastating to youth populations
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The bubonic plague outbreak, commonly known as the Black Plague or the Black Death
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swept across Europe, Western Asia, and North Africa starting around 1346. And that's not just a spooky nickname
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It really was among the most fatal pandemics in recorded human history, causing an estimated 75 to 200 million deaths
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That's about 30% to 60% of the entire European population at the time, completely removed
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like a bad tattoo. For a long time, historians believe that the plague reached Europe and spread so quickly
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due to the Mongol conquests of the 14th century. But there's ample evidence backing up alternate theories
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For example, fleas traveling on rats living on Genoese ships may have carried the illness
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around the Mediterranean, including North Africa and throughout the Italian peninsula. That's a nesting doll we don't want to play with
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Plague remained an ongoing concern for Europeans for several hundred years. The final major outbreak occurred in London in 1665, an often estimated 100,000 people
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about a quarter of the city's entire population, in just 18 months
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London in this period was both dirty and crowded, making it an ideal breeding ground for plague bacterium
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Poorer parts of the city were densely overpopulated, filled with crowded tenement buildings and
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a sanitation system consisting of open drains flowing through the city streets
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Just a lot of uncovered poop rivers. So think about that the next time you complain about English weather or weird breakfasts
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It could always be worse. Let's switch gears to syphilis, which is something you never want to hear from your general practitioner
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This illness is also caused by a bacteria and typically gets spread during sexual contact The infection progresses in four stages starting with sores on the skin followed by a rash and potential mouth sores and then a latent period without new symptoms
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which can last for several years, during which time patients remain symptom-free
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but can be as infectious as a tasty groove. But then, the final stage involves non-cancerous growth
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surround the body, plus neurological and heart symptoms, which can include dementia, seizures, and severe depression
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The earliest historical report about a syphilis outbreak occurred during France's invasion of Naples, Italy in 1494
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For a time, the illness was known as the French disease because of this connection
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The term syphilis didn't arise until it was used by Italian physician and poet Girolamo
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Tracostoro in 1530. Sacre bleu. In a fortunate stroke of luck, syphilis was the first major new disease to be recognized
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and diagnosed following the development of the printing press. News about the disease, how to detect it, and how to avoid it spread far more quickly
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because of this innovative leap in mass communication. Think of these as history's first, the more you know, PSAs
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Historians still don't exactly know how syphilis came to Europe. Some argue it had already existed, but just been misdiagnosed as other illnesses
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Syphilis was sometimes referred to as the great imitator because its symptoms can so readily resemble other illnesses
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like a vaudevillian impressionist. Others theorized that syphilis actually started in the New World
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and came back to Europe along with Christopher Columbus's crew. This vast transfer between old and new worlds became known as the Colombian Exchange
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While syphilis potentially spread from Caribbean populations to Europe, illnesses passing from European travelers to American natives were far deadlier
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A 1493 outbreak of the swine influenza devastated the Taino population in the Caribbean
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Measles, whooping cough, chickenpox, typhus, and malaria were also concerns. But by far the most devastating European illness to spread through the Americas was smallpox
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smallpox. An estimated 40% of the population of the Aztec capital Tenochtitlan succumbed to
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smallpox in 1520 during the invasion of conquistador Hernán Cortés. Hey, we did an entire episode
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about that guy. Spoiler, he was not a chill dude. In general, disease wiped out far more Native
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Americans than war. Around 80 to 95% of the total Native American population perished in epidemics
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within the first 150 years after Columbus arrived in 1492. They tend to leave that part out of the ocean blue rhyme
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Cholera became a global concern during the 19th century, but it's still unclear whether the world ever suffered a technical cholera pandemic
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What is clear is throughout the 1800s at least five large outbreaks occurred that caused the loss of around 1 million human lives The first known outbreak hit between 1817 and 1823 starting around India Ganges River
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It spread quickly across the Indian subcontinent, then to Southeast Asia, the Middle East, Africa, and ultimately, Europe
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The years 1852 to 1859 saw the most concentrated cholera deaths of the century
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It was this outbreak, specifically the London arrival of cholera in 1853, that inspired English
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physician John Snow to investigate the disease, like some sort of germ detective. At the time
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most experts believed that illnesses like cholera were caused by pollutants in the air
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But Snow rejected this hypothesis. He spoke with locals around Soho and was ultimately able to
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trace infections to a single public water pump on Broad Street. The germ theory of disease had
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not yet been established, so Snow didn't understand specifically how the illness was
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passing from the pump to the people who used it. He just knew the water was no good for anyone
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But his work still led the city to disable the pump, which was widely credited with ending the
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outbreak. Today, Snow is considered the father of epidemiology, the study of how diseases spread
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Unlike John Snow, looks like this Snow did know something. During the COVID pandemic, we all heard a lot about the Spanish flu of the early 20th century
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Estimated to be the most devastating pandemic in human history, the Spanish flu took out between
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20 and 50 million people in the Americas and Europe between 1918 and 1920. That's four times
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more casualties than the entirety of World War I, which are pretty good numbers for a disease
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Despite its name, it's unlikely the Spanish flu actually started in Spain
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Because the outbreak began toward the end of World War I, news about the illness spread
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slowly in fighting countries. Local press would often simply avoid negative news topics for fear of impacting morale
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But in neutral Spain, the outbreak was more widely reported, leading to the false impression
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of the disease's origin. It's considered more likely by contemporary researchers that the Spanish flu actually
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started in China, potentially as an avian flu that passed into humans
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A number of factors, including anomalous climate patterns and overcrowded hospitals, allowed the disease to spread more quickly
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Additionally, while many influenza outbreaks disproportionately impacted children and the elderly, the Spanish flu had a particularly devastating effect on young adults
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Which brings us to the present day. Besides COVID, a number of other infectious diseases remain a significant concern
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The list includes Ebola, SARS, and even tuberculosis. That particular illness has been curable and preventable for many years
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contemporary people have also been struggling with the onset of door dash itis
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an affliction that causes you to spend too much money ordering out