by Ana Wang
In these times of the COVID-19 pandemic, you have probably heard many mentions and comparisons of this current, world-wide crisis to the 1918 flu (a.k.a. the Spanish Flu) pandemic. In difficult times in our history, re-visiting and learning from past events can teach us much about how to handle modern, similar situations. There are many parallels that between the pandemics of 1918 and 2020, so let’s delve a little deeper into what happened 100 years ago and see how it relates to our world today.
What is a pandemic?
WWI soldiers being treated during the 1918 pandemic. American Unofficial Collection of World War I Photographs, Getty Images
A pandemic is when a disease has spread throughout a country, continent, or the world. This is different from an epidemic, which is a rapid spread of a disease within a locality, like a community or a region. The 1918 influenza (shortened to “flu”) and the 2020 COVID-19 outbreaks are both global pandemics because there have been (and still are) cases all around the world. It is estimated that the 1918 pandemic claimed about 50 million lives. As of this writing, the 2020 pandemic has claimed about 2.2 million lives.
How did the 1918 and 2020 pandemics start, and how did they spread?
In the industrial era of 1918, there were new forms of transportation that helped the flu spread more quickly, not to mention an ongoing world war. Now, in the 21st century, we live in an extremely globalized society, in which people travel very frequently, for both pleasure and for business, around the world. This unfortunately allows viruses to spread around the world at a quick pace.
Viruses are not living organisms; they require a host (e.g. humans) to reproduce. A virus reproduces by hijacking the biological processes and tools in its hosts’ cells to replicate itself. People who are carrying a virus can spread that virus unknowingly to anybody with whom they come into contact. This is why many countries during the COVID-19 pandemic have implemented travel bans and discouraged travel.
Although the 1918 flu is informally known as the Spanish flu, the name is misleading, as it likely did not originate in Spain. The name stuck because the Spanish press was the first to publish information about the pandemic; Spain was neutral in World War I, and news of the war dominated the press of the countries involved in it. Furthermore, many countries censored the publication of information about the pandemic because they were afraid of causing public panic. There are several hypotheses about where the 1918 virus originated, and none of them trace back to Spain.
Similarly, during the 2020 pandemic, COVID-19 was referred to by many as the “China virus,” or the “Wuhan flu” because the first diagnosed and publicized cases occurred in Wuhan in the Hubei province of China. Theories about the virus’s origins say that the virus escaped or was released from a research lab in Wuhan. This is highly unlikely as genetic mapping shows that the virus was born in nature, not a lab. The exact origin point of the virus is not known. Additionally, the name “Wuhan flu” is misleading as COVID-19 is caused by SARS-CoV-2 - an entirely different virus from influenza. (SAR-CoV-2 is the name of the virus that causes COVID-19, the disease. Science has separate names for the virus itself and the resulting illness).
A checklist of symptoms caused by the 1918 H1N1 virus. By Otis Historical Archives nat'l Museum of Health & medicine (OTIS Archive 1) -
The 1918 flu was caused by the H1N1 virus. (You may recognize the name ‘H1N1;” it was a different H1N1 virus that caused the “swine flu” in 2009-2010). One of the first documented and established cases of an infection by the H1N1 virus, the virus that caused the 1918 flu, was on March 4, 1918 in a cook named Albert Gitchel at Camp Fuston in Kansas. Within only three weeks, that one case led to thousands of cases, with 1,100 soldiers hospitalized. H1N1 was further spread throughout Europe, wreaking havoc on the World War I military operations. Although this first wave of infections showed that the virus was very contagious (meaning it spread easily), it was not initially extremely virulent (meaning harmful or deadly). However, the virus soon underwent a dangerous change.
A model of the Coronavirus virion structure. By SPQR10 - Own work, CC BY-SA 4.0
Mutations and new virus strains
Why do viruses change? When a virus finds a host (meaning it infects an organism), it uses the host’s machinery in the cell to reproduce itself. This involves a very rapid process of making copies of the viral genes for the new virus particles being made. The speed helps the virus replicate quickly, allowing it to infect more cells quickly before being detected and attacked by your immune system. During this process, copying errors occur. Think about when you are doing work or typing/writing very quickly; you are more likely to make mistakes when you are rushing than when you take your time. These copying errors, or mutations, get packaged into new virus particles. Some of these errors may have no effect at all, while other errors can make the new virus more contagious and/or more harmful for hosts.
A more dangerous virus emerged in August 1918, when there was a second wave of H1N1 infections. This new strain was believed to have been spread by passengers on ships from Plymouth, England to Sierra Leone and to Boston, USA. The virus was further carried with the movements of the armies, so you can imagine how expansively and quickly it spread across all continents! In the first strain, there were mild, short-lived symptoms that we generally associate with the flu, such as fever, aches, and coughing. In this new, mutated strain, symptoms included nasal hemorrhage, pneumonia, encephalitis, deadly fevers, and coma.
If you are keeping up with the COVID-19 pandemic, you have undoubtedly heard about the new strains that have been recently identified in the U.K. and South Africa and are already spreading to other parts of the world. Although copying errors of viral genes are happening all the time, and therefore new mutants are being made all the time, most often these strains do not have a noticeable effect on the transmission or severity of the virus. Once in a while, however, a mutant strain will catch our attention. In the U.K. and South African mutants, the copying errors that occurred may have rendered the SARS-CoV-2 virus more contagious and possibly more virulent. Even more concerning is that the vaccines that have been produced might not be as effective against the South African strain. To be clear, the vaccines do appear to provide protection against the new strains, but they are less effective.
Why the speed of vaccination is crucial
Now that you understand the phenomenon of how new virus strains are created, you can understand why it is so important to get pandemics under control quickly. The more cases of disease there are, the more virus that is produced. The more virus that is produced, the more mutations that can occur. The more mutations that occur, the more likely we will have cases that can cause more and deeper problems with elusive solutions.
Children lined up for the flu shot in New York City, late 1940s. Library of Congress.
To put it plainly, if the virus continues to spread uncontrolled, new strains will pop up that may be more transmissible or more deadly than any we have seen so far. Vaccines not only fight spread of the current virus, but decrease the chances of new, even deadlier strains emerging.
A sign from the Cincinnati Board of Health Streetcar, educating people how to protect themselves from the flu. CDC.
Until we are all vaccinated, other measures to contain the virus need to be continued. Because we have long known that viral infections spread largely by human-to-human contact, similar guidelines implemented in 1918 are being used today; wearing masks, limiting gathering, and avoiding stuffy, indoor environments have been known to be effective for fighting pandemics for over 100 years!
Lessons Learned
What can we learn from the 1918 pandemic that will help us manage current and future pandemics? Although H1N1 and SAR-CoV-2 are different viruses, the way they spread and their economic, social, and medical impacts can be very similar. Although we understand much more about viruses now than was known in 1918, and even though we have improved treatments for symptoms, the goals in both cases are the same: to minimize the number of cases to limit damage.
The blue “circles” here are SARS-CoV-2 in a slice of tissues as seen through a transmission electron microscopic. PHIL 23354, CDC.
To control spread of the virus we need to follow the guidelines given by the Centers of Disease Control and Prevention (CDC). To protect yourself and those around you, remember to wash your hands, wear a mask over both your nose and mouth, stay in well ventilated areas, avoid large or close gatherings, and get vaccinated when it is your turn. The actions of every individual matters in a crisis this large. The more that people follow the guidelines, the more quickly and more safely we can end the crisis. Although it’s been a hard year for most of us, the vaccine brings hope for easier times soon. Every time you make the decision to stay at home, wear a mask, or engage only in outdoor physically distanced activities, you are saving lives!
References
“‘The 1918 flu is still with us’: The deadliest pandemic ever is still causing problems today.” The Washington Post. https://www.washingtonpost.com/history/2020/09/01/1918-flu-pandemic-end/. 30 January 2021.
“The Spanish Influenza Pandemic: a lesson from history 100 years after 1918.” Journal of Preventive Medicine and Hygiene. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6477554/. 30 January 2021.
“The Deadliest Flu: The Complete Story of the Discovery and Reconstruction of the 1918 Pandemic Virus.” Centers for Disease Control and Prevention. https://www.cdc.gov/flu/pandemic-resources/reconstruction-1918-virus.html. 30 January 2021.
“Medical Innovations: From the 1918 Pandemic to a Flu Vaccine.” The National World War II Museum, New Orleans. https://www.nationalww2museum.org/war/articles/medical-innovations-1918-flu. 30 January 2021.
“Pandemics in Recent History.” Knowable Magazine. https://knowablemagazine.org/article/health-disease/2020/pandemics-recent-history. 30 January 2021.
“Why the Second Wave of the 1918 Flu Pandemic Was So Deadly.” History. https://www.history.com/news/spanish-flu-second-wave-resurgence. 30 January 2021.
“The Proximal Origin of SARS-CoV-2.” Nature Medicine. https://www.nature.com/articles/s41591-020-0820-9?fbclid=IwAR3w65RgILi01mVjIMQ2LKeZS4xUkLz5LRBinImTKRPOWSnCqIQWw_hDzR0. 31 January 2021.