How a Flattened Curve Becomes a Plateau

April 2020 was a remarkable month. On one hand, the world witnessed the most devastating pandemic of our lifetime wreak havoc on the lives of millions. Between thousands of lost lives, the upheaval of the norms of daily life and a massive economic fallout, April left a mark on the lives of almost every person on the globe. On the other hand, countries around the world witnessed a level of solidarity not seen in years. With some exceptions, people rallied around the cause of “flattening the curve” and in doing so saw the impact of cohesive public health measures in halting the spread of Covid-19. As April turned to May, trends began to show the outcomes of our efforts as curves across the country flattened. US states hardest hit by the virus like Washington and New York, began to see glimpses of a curve turning downward. It appeared that our efforts were working.

By late May, US citizens became exhausted and impatient with the pandemic. Economic pressures forced people to come out of stay-at-home orders and return to a modified version of normal. Soon, states began to show differing trends in coronavirus cases, with many trends going against the hope that summer would tamp down the virus. By mid-June, several states were showing a rise in new cases of the virus. It was clear that we were no longer on a curve, we were atop a plateau. With people returning to divisive rhetoric around safe gathering and masks, Covid-19 seemed to become a political issue and the solidarity of April was lost.

Mask Resistance

By mid-June, one of the most contentious issues surrounding Covid-19 was mask wearing. As states began to open up, impassioned pleas went out to people asking them to simple carry and wear a mask. Some states required the use of at least a cloth mask when entering indoor public spaces. There seemed to be an unavoidable momentum, but many experts felt that the use of a simple face mask would dramatically cut the level of transmission of Covid-19.

Image by Juraj Varga from Pixabay

Ironically, when early stay-at-home orders were put into place in March, there was run on personal protective equipment (PPE) — N95 masks in particular. The demand for protective masks was so sudden that manufacturers fell short of providing even the most needy places like hospitals and nursing care facilities with adequate supplies. The massive public demand for protective masks seem to signal that people felt they were a critical to avoiding infection. So how did the March demand for masks turn to June resistance to wearing them?

The answer to that is multifaceted, involving human psychology, social behavior and US citizen’s sentiment around requirements for personal and social behavior.

On one hand, not wearing mask is self perpetuating. In a crowded space, people are subject to the pressures of social behavior, and struggle when placed in the position of being singled out. Early experiments by Solomon Asch demonstrated the power of conformity when individuals are placed in positions of social pressure. In one of the more memorable experiments a team of people was place in an elevator — facing backwards. As the elevator door opened to an unsuspecting person, they entered the elevator clearly perplexed by the obvious divergence from social norms. Hidden cameras caught most people conforming to the behavior within seconds. As businesses begin to open up, and people start to gather at stores and outdoor restaurants, it is easy to fall prey to these pressures when surrounded by unmasked people. As one of few people wearing a mask, it is easy to feel that you are the “odd one out” and to conform under social pressure.

People are also remarkably responsive to modeled behavior. People’s individual, social and economic behavior is strongly influenced by that of persons of influence like celebrities and politicians. When Elvis Presley went on national TV to receive his polio vaccine, the rates of vaccination skyrocketed not long after. As a person of influence, people — whether consciously or otherwise — began to model their behavior after Elvis in ways unrelated to his music.

A similar, but opposite effect can be seen today. To date, there have been very few instances of either president Trump or vice president Pence wearing a mask in public. Whether for political reasons or an effort to maintain appearances, their behavior serves as a model for millions of people. Given what people see from their leader, it is no surprise that many became resistant to wearing masks.

Finally, US citizens are notoriously resistant to requirements on personal behavior that may be seen as an infringement of civil liberties. There are countless examples of push-back against regulations on personal behavior ranging from smoking to seatbelts. Some regulations — like smoking — involve obvious impacts of these behaviors on social wellbeing. Other behaviors — like motorcycle helmet laws — are more abstract in their impacts to society. Mask wearing is no exception as the consensus on their effectiveness in preventing disease spread and illness has become murky and divisive.

Masks over Social Distancing

The effort to flatten the curve born in early March was built around one thing — social distancing. State and local policy, the closing of businesses and broadly enacted stay-at-home orders were all centered around keeping people out of close proximity. Most experts believed that the one variable that would tamp down the spread of Covid-19 was people’s social interactions. What resulted in April was that trends of new Covid-19 cases began to level off. These results were seen more in some states than others, but it was clear that our social distancing efforts were paying off.

With summer fast approaching, and people’s patience with stay-at-home restrictions waning it seemed inevitable that states would begin to open up. Some states rushed to ease restrictions on businesses and workplaces, which allowed the release of social pent up energy. As businesses began to open, the message began to shift away from social distancing to the use of protective masks, signaling that public gathering would be acceptable so long as masks were used.

The effort to flatten the curve never claimed that social distancing should be eased at the apex of the curve. In fact, the apex of the curve of Covid-19 cases shows the highest number of infected people. Logic would have it that at this point, social distancing is most critical. Instead emphasis was placed on masks and social distancing practices began to fall by the wayside.

Masks offer limited, albeit valuable protection against infection. This protection varies dramatically between a N95 mask and a bandana or homemade cloth mask. Despite this, mask wearing may give people a false sense of security leading to easing of social distancing practices. As we move from a flat curve to a June plateau, social distancing remains as important as it was in March.

The Young and the Restless

With new Covid-19 cases leveling off, and in some states beginning to rise again, there is one interesting discrepancy in the data. With new cases on the rise in many states, death rates are dropping. Experts feel that this signals a shift in the demographics from older to younger people becoming infected.

Source: https://www.ecdc.europa.eu/en/covid-19-pandemic

Though we have seen that Covid-19 spares no population from infection or death, the majority of data still shows that older people with preexisting conditions are most susceptible to severe illness or death. The inverse relationship between new cases and deaths that was recorded this month seems to point to the younger and less susceptible populations testing positive for Covid-19.

In fact, it is true that in some states the percentage of new Covid-19 cases is shifting toward younger populations. In California, the rate of new Covid-19 cases in people under 35 went from 29% to 44% in just one month. Children and teens are also included in the rise in new cases making them easy carriers of the virus.

Perhaps the messaging around flattening the curve should have included the effort to round off the curve

Months of being cooped up at home, unable to attend school and social functions like birthdays and graduations has left young people feeling restless and impatient. As businesses begin to open up, young socially active people will begin to gather once again to enjoy the warm summer months. In doing so, they will perpetuate the spread of Covid-19.


Currently, we may be in the midst of a massive misinterpretation of the flatten the curve movement. Social distancing efforts of the Spring did lead to some flattening of curves around the globe, but data in the US seems to show that we are atop a plateau rather than descending from the apex of the curve. The economic and social pressures felt by many may spur people to break from social distancing practices and begin to gather. Whether masked or unmasked, social distancing still remains the most powerful tool we have against the spread of Covid-19. Perhaps the messaging around flattening the curve should have included the effort to round off the curve, and reopen only when there is a sustained decrease in new cases. Until then, a plateau is the best we can hope for.