What is "flattening the curve?"

What does “flattening the curve” mean? What “curve” are people even talking about? Where did this phrase even come from?

A viral article, or more specifically a graph accompanying the article, about limiting the spread of COVID-19 popularized the term “flattening the curve.”

. *A similar graphic is shown below.

What does this graph even show, and what do those curves mean? The graph shows two different situations of how the virus can spread and the curves illustrate the number of people sick from COVID-19 at certain points of time.

Notice how one curve is sharp while the other curve is flat. It may look like one curve represents more cases than the other but both curves show the same overall number of cases. The difference that distinguishes the two curves is time. The sharper curve shows many cases occurring over a short time period while in the other situation the same number of cases are more spread out. The flatter curve depicts our ideal situation. Some may ask why we want the situation demonstrated by the flatter curve. It seems like when comparing the two peaks, the situation with the sharper curve is “better” since that means the virus will spread for a shorter period of time. Why would we want to prolong the amount of time the virus spreads, which means taking a longer time to get back to “normal life”?

Imagine it’s Black Friday. Thousands of people are trying to get through a single door into a store to buy the latest phone. Only a few people would be able to get through the door at a single time and even if the thousands of people were able to get through the door it would take a long time. The store also has a limited capacity, which would make even walking through it an uncomfortable experience in comparison to your everyday shopping experience. Furthermore, if you were not one of the first people to get through the door you would most likely not get the latest phone due to limited supply. Even if you were to get the phone initially you would have to wait in long lines to pay for the phone because there are only a limited number of cashiers.

Now apply Black Friday to this pandemic. Though the sharper curve looks like we would get the virus “over with,” this is not an ideal situation for our healthcare system. Take note of the dotted line on the graph labeled “how many very sick people hospitals can treat.” Notice that the sharper curve surpasses the maximum number of people our hospitals can handle while the flatter curve stays below the maximum. If we surpass the maximum threshold, hospitals would not be able to provide the care patients need, leading to higher death rates by COVID-19. Doctors would not be able to provide the quality of treatment needed for each individual patient due to shortage of staff, equipment, beds, etc. Doctors in this situation will also be forced to prioritize who gets to live and who dies because they won’t have enough resources to treat everyone. Doctors and nurses are also more likely to get infected by COVID-19 due to higher infection rates, which decreases the number of staff available to treat patients.

However, if we “flatten the curve” i.e. decrease infection rate by COVID-19 or the number of infected people, hospitals would be able to provide the quality of care patients need to survive. As a result, death rates would significantly decrease. Furthermore, this graph only represents a model of the two cases; in the case of the sharper curve, we would in reality witness more cases in comparison to the situation with the flatter curve because the sharper curve represents a significantly higher infection rate.

So what can we do to flatten the curve? Health experts advise everyone to wear masks, social distance, and avoid large social gatherings to slow the spread of the virus.

*Read our other sections about masks and social distancing.

Initially, in March 2020 COVID-19 overwhelmed Italy’s healthcare system. In Italy, cases rose exponentially and the number of COVID-19 related deaths even surpassed China, who at the time was number 1 in the world for COVID-19 deaths. Doctors reportedly were forced to choose which patient would receive resources such as ventilators, ICU beds, etc. for treatment. Hospital staff were overwhelmed as hospitals reached maximum capacities and many doctors, fighting to keep their patients alive, died from the virus. However, Italy, the model other countries feared to become, managed to significantly flatten the curve, and became a model countries hoped to become.

How did Italy manage to flatten the curve despite an exponential increase in the number of COVID-19 cases? Within days after the first reported COVID-19 cases, the Italian government sealed off towns with the help of police and military support. They then shut down schools and businesses in the Lombardy region, where Patient One was reported on February 20. The government then moved to impose lockdown on the entire country on March 9. They closed down all businesses, tourism, and schools. They even restricted movement. People had to fill out “auto-certification” forms which people had to fill out to prove their need to go outside, and local authorities enforced social distancing and mask regulations through large fines.

Overtime, Italy managed to flatten the curve. They shut down the first wave by limiting transmission through compliance of the people and enforcement by the government. Italy has eased lockdown measures starting May 4, and citizens resumed “normal life.” However, Italy is witnessing a resurgence of cases as of late September, most likely attributed to the ease of lockdown measures.

The overall takeaway: in principle we know how to fight the infamous COVID-19. While this pandemic may seem like something we have never faced before and seems like an “impossible” fight against an invisible enemy, we can control how this virus impacts us. All we need to do is “flatten the curve.”