In times of crisis, it can be rewarding to turn to history as a learning tool, helping to both avoid past mistakes and replicate past successes. As panic in response to COVID-19, a pandemic that recently caused the shutdown of all Palo Alto Unified School District schools till April 13, rises, this process becomes incredibly important as a mechanism to explore what each of us can do to improve the situation. Through an analysis of four major health crises, including the Spanish Flu, Severe Acute Respiratory Syndrome (SARS), the Swine Flu and the H2N2 virus, commonly referred to as Asian Flu, as well as comparisons to modern-day COVID-19, it is possible to learn many lessons about how to prevent a pandemic. 

COVID-19 is believed to have originated in a “wet market” in Wuhan, China,  possibly coming from transmission between the animals there and humans, but probably originating in bats. SARS, which is thought to have also originated in bats, first saw cases in Zhongshan City, China possibly due to other “wet markets” there while the H2N2 virus, which came from ducks, was first seen in Guizhou, China. The Swine Flu started in Veracruz, Mexico near a pig farm (and the Spanish Flu’s origin is mostly unknown but some hypotheses include a British army base in France, Fort Riley in Kansas and, more recently, somewhere in Northern China). 

This seems to suggest that the highest risk areas for the start of epidemics tend to be places where humans are in close contact with live animals, such as a farm or “wet market.” These diseases tend to be zoonotic, meaning they spread from non-human animals to humans. In fact, it is possible for zoonotic diseases to show no symptoms at all in the non-human animal but severely affect humans due to differences in immune systems. 

One of the most important parts of the timeline of a pandemic is its “spread,” or what allowed it to go from one case to thousands. One reason is close proximity to other people. The Spanish Flu is one of the clearest examples of this, as it is mostly thought to have moved through World War 1 bunkers where soldiers were shoved into cramped places and spent weeks living inches away from each other. It infected over 500 million people and killed over 50 million, globally lowering the average life expectancy by 12 years. 

Still, one of the things to watch out for in comparisons between pandemics, especially between COVID-19 and the Spanish Flu, is the time period during which the pandemic occurred. In 1918, the medical field had not advanced nearly as far as it has today. Key innovations such as respirators or more protective medical gear were simply not available, meaning that more people got infected and treatment was less effective. That’s not to say that COVID-19 is not bad, it is a fast-spreading dangerous virus, but that its spread (and casualty rate) is inhibited by technology that did not exist at the time of the Spanish Flu. This lack of technology helped allow for the Spanish Flu to spread rapidly and kill over 50 million people.

Specific features of each of these viruses also made their transmission more likely. One of the reasons COVID-19 is spreading faster than SARS is because, according to Vox, it replicates in the upper respiratory tract rather than the lower one, allowing it to transmit even without the host showing any symptoms. It’s very likely that teenagers and young children may not show any symptoms at all but act as carriers to the disease, spreading it to people that may be more affected, such as elderly grandparents. The Swine Flu, a strain of influenza, was also special due to its ability to infect people of various age ranges rather than other strains of influenza which disproportionately affected those over 60 years old. 

The next step in the timeline of a virus is containment: how did government or social policies help to curb the virus’ spread? Quartz’s article on the Spanish Flu, which compares the spread of the flu in St. Louis, Missouri and Philadelphia, Pennsylvania helps to highlight the necessity for social distancing. Specifically, while Philadelphia held a war march of over 200,000 people while in the middle of the pandemic and ended up overflowing its hospitals with cases, St. Louis was able to effectively reduce its cases by closing most public centers (including schools) in the first two days, and banning public gatherings of over 20 people. 

This concept, commonly referred to as “social distancing,” seems to be the best way to combat contagiousness. Whether implemented through government policy, like the recently announced lockdown of all non-essential Bay Area businesses, or through social norms where people agree to limit the spread of the disease, it can be one of the only ways to at least slow down the spread. 

However, self-quarantine requires trust of governments: both to believe that the measures are necessary and that the crisis is real. Some countries attempt to bypass that necessity for trust by brutally enforcing policies, often leading to a more effective containment but worse quality of life. For example, according to Eugenia Tognotti’s article “Lessons from the History of Quarantine,” Chinese police during the SARS went as far as to install Web cameras in homes to maintain the quarantine, while also imposing harsh punishments such as the death penalty on those who violated the quarantine. Although these policies helped to significantly reduce the spread of the virus, it is up to the individual to decide whether invasion of privacy is worth that reduction. Still, self-quarantine will always be effective by limiting interactions and stopping the infections from getting worse.

The final step of a pandemic is its resolution, typically when the World Health Organization (WHO) declares it to be in its post-pandemic stage. This doesn’t mean that cases don’t continue to happen, but rather that there are no large or unusual outbreaks of the virus. Each of the four pandemics assessed ended in a couple years, with the Spanish Flu lasting from 1918 to 1920, the Swine Flu pandemic lasting from 2009 to 2010, the H2N2 pandemic lasting from 1957 to 1958 and SARS lasting from 2002 to 2004.
None of these resolutions came directly after one significant step taken, but rather individual events that compounded together to inhibit the spread. Developed immunity, the rise of vaccines, quarantine policies and even changing weather all played a part in finally ending these pandemics. When we look at COVID-19, it is our responsibility to each individually do our best to help this crisis reach that post-pandemic level quickly. By following policies set forth by local governments, practicing “social distancing” and listening to other key lessons from history, we can each make an impact on working toward the resolution of this crisis.