Welcome to OMG Medical History, a short podcast from On Medical Grounds where we talk about interesting topics and events in medical history. Join me for a cup of coffee as we talk about the interesting, the amazing, and sometimes the frightening.

Today, as we are in the midst of a horrible respiratory illness season and yet another round of COVID, we here at On Medical Grounds thought it apropos to discuss the history of the other great pandemic causing virus of our time, the notable, and horrendous, flu. With the rise of COVID, there were a lot of comparisons made to the 1918 flu, another dark time of deaths, mask mandates, and misinformation. But the 1918 flu wasn’t the first flu or even the first flu pandemic. Where did it all start?

To provide you an honest factual answer, as we always strive to do here at On Medical Grounds, we have to confess that we don’t actually know. But we will tell you what we do know. Prior to 1933, people believed that causes of this mystery illness included natural disasters, such as earthquakes, volcanoes, and vapors from the ground, or astrological events such as comets or cosmic dust from the rising and setting of the sun. In fact, in the 1500s, the name “influenza” was coined as a term for an influenza-like illness raging throughout Europe, Asia, and Africa. In Italy, it was thought that illness was caused by a maligned influence (or influenza) from the stars, thus the name we all know and fear.

The first person to claim to have actually isolated something that caused the flu was Dr. Richard Pfeiffer, of the University of Breslau in Prussia. In the late 1800s he isolated a bacillus species from nasal swabs of patients with the flu and named it Bacillus influenzae. Many of his colleagues disagreed that this was what caused the flu. And they were correct. Some of his compatriots of the same time noted that it could also be caused by a virus. However, it wasn’t until the 1933, almost a half century later, that British scientists Wilson Smith, CH Andrewes, and PP Laidlaw isolated the virusand the viral theory was accepted.

Because prior to the 1930s no one knew exactly what caused the flu, much less how to test for it. If we want to know more about flu and flu pandemics, we are left scouring historical records for sets of clinical symptoms. After the 1800s, this was easier. Flu-like symptoms were mostly well defined, and pretty much everyone wrote things down. However, prior to that time period, we can only make educated guesses. The earliest mention we can find of a flu-like illness is a Sanskrit term “Plu” from around 1200 BCE describing an illness with cough, headache, fever, eye pain, tears, and a runny nose. And there are records suggesting flu pandemics back to around 800 ACE. But given that information, most historians consider Hippocrates as the first author of description for an influenza-like illness in the 5th century BCE, specifically 412 BCE, in his “Book of Epidemics.” In this text, he describes a syndrome called the “Fever of Pernithus” or “Cough of Pernithus,” which was a winter and spring epidemic that commonly occurred in the old Greek port town of the same name. It is unclear, however, if Hippocrates was actually describing the flu, as some historians and later physicians believe he might have been describing diphtheria or a vitamin A deficiency.

Another controversial mention of something that may or may not be a flu pandemic, occurred in Aztec writings in the mid-1400s in the area of what is now Mexico. Historians debate whether what was described as a “pestilential catarrh” was already present in the Americas or was brought over from Europeans. This written description would, in modern times, refer to congestion, mucous, phlegm, and often a fever, but we have to note here that the manuscripts in question are difficult to translate, so we aren’t sure of the accuracy of the interpretation.

The first documentation of the flu that is generally considered reliable occurred in 1510 when the virus spread from Africa to Europe. There is mention of a “pandemic” that occurred in the mid-1500s but there are many questions as to whether this was actually flu. The first true flu pandemic of record , occurred in the late 1500s. In 1580, a flu pandemic appears to have started in Russia and Asia, quickly spreading to Africa and Europe, and later the Americas. The severity of this pandemic is not fully documented but we do know that over 8,000 people died in Rome and entire populations were lost in several Spanish cities. This 1580 pandemic was the same event that I mentioned earlier where influenza got its name.

Over several centuries, from the 1400s to the 1800s, there were upwards of 31 outbreaks and 8 true pandemics. One of those notable pandemics was the “Russian” flu pandemic of 1890. Papers throughout Europe described the scene. Special tents were set up as sick wards. People who were too sick to work were handed donations from those better off and their local governments. Pictures of the sick and dying were displayed. Sound familiar?

Another three pandemics occurred in the 20th century and this, my friends, brings us to the year 1918. The infamous 1918 flu, sometimes called the Spanish flu, was described as the “greatest medical holocaust in history” by Dr. JI Waring of South Carolina in the medical text he authored in 1964. This flu pandemic had two main phases and infected up to 50% of the world’s population, causing between 21 million and 100 million deaths. The pandemic was first seen in military members, with the first outbreak in the U.S. occurring in the spring at Fort Riley, Kansas. By October of 1918, 24 countries had reported cases.

Why was it called the Spanish flu? Because 8 million of the early deaths came from Spain. The country was absolutely ravaged. The 1918 flu killed more people than the entirety of World War I. Because we were still in the trenches of World War I at the beginning of the pandemic, the flu didn’t have much lasting cultural impact at the time. And as we saw when COVID arrived, some people didn’t learn their lesson. There were signs posted about dangers of spitting, coughing, sneezing, or anything else that might increase the spread. Businesses and schools closed. There were pictures in papers of tents with rows upon rows of the sick and dying. Hospitals and morgues were overwhelmed and there weren’t enough healthcare providers to go around. The Red Cross was called in across the country and did everything in its power to help. Cloth masks were a thing and many cities mandated them. This caused an uproar as the flu reached its second peak. Much like we experienced with COVID, early mask mandates were somewhat tolerated, while later mask mandates were not at all well received and the second wave of the flu pandemic was much worse. The masks available at the time were cloth, and as we saw with COVID, they aren’t the best at preventing the spread of viruses. In one year, the 1918 flu decreased the U.S. life expectancy by over 10 years.

The other two pandemics of the 20th century were not as severe and occurred in 1957 and 1968. The most noted flu pandemic of the 21st century was the 2009 H1N1 “Swine Flu” pandemic, which originated in the U.S. before spreading around the world. And that brings us up in history to where we are now, looking at a flu season that is once again battering people and hospitals. Fortunately, this one hasn’t shown signs of being declared a pandemic, so hopefully it will end over the next couple of months. But future pandemics are always a possibility and something to be prepared for. Our best defense is to get our flu shots.

I hope everyone enjoyed our little foray through the history of the flu and flu pandemics. The references used in today’s podcast are listed in the show notes if you would like to do a little digging for yourself.

Do you have any other topics or events in medical history you would like to hear about? Let us know! We are on Twitter, Instagram, and LinkedIn. Comment on one of our posts or tag us on other posts that you would like to hear about. And make sure to subscribe and join us next time at On Medical Grounds for a little bit more medical history or one of our current topic interviews. I hope you all have a wonderful day. Remember history is there for us and we can learn from it.

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Vosburgh H. Flu Epidemic of 1918. Kansas Historical Society. https://www.kshs.org/kansapedia/flu-epidemic-of-1918/17805. Accessed 01/13/23.
https://www.who.int/news-room/spotlight/history-of-vaccination/history-of-influenza-vaccination. Accessed 01/13/2023.
https://www.history.com/topics/world-war-i/1918-flu-pandemic. Accessed 01/13/23.
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