I entered medical school with a commitment to public health, and I hope to train to become a critical-care physician in order to treat the sickest of the sick. I thought my work in free clinics in West Philadelphia had taught me how structural factors like poverty, racism, and injustice set my patients up for poor health. I thought I understood. Then COVID came. This pandemic exposed the underlying injustices that plague our health-care system, and our responses have amplified and restructured health risks and outcomes.

In cities across the U.S., gun violence has risen to levels not seen in a decade or more. We created a team to study this change at the University of Pennsylvania and found that the lockdown order instituted in March was associated with a sharp increase in interpersonal violence. We found that even though accidental injuries and emergency room visits for urgent conditions like heart attack and stroke decreased, those coming in for firearm injuries skyrocketed.

Specifically, gun violence rates went up for Black individuals while it decreased across all other races. Furthermore, we found that more young men were coming in due to firearm injury than before. In short, once the city of Philadelphia locked down to prevent the spread of the COVID-19 virus, young Black men began getting shot at staggeringly higher rates than at any other point in time in recent years, and more so than any other demographic during these same months.

Firearm violence has been at epidemic proportions in the United States for years, with close to 38,000 lives lost each year, and at least twice as many who are injured but survive. A male in the United States is 70 times more likely to die of gun violence than in other equally developed nations. This epidemic is concentrated among Black adolescents and young men, and rising rates of violence in Philadelphia and elsewhere continue to affect this group most severely.

Simultaneously, we know that isolation derails key elements of social interaction, including communication, basic supply availability, and finances, therefore altering how individuals behave. Going into lockdown, it would have been reasonable to think that there would be a decrease in the amount of firearm injury, due to decreased interaction between individuals. But unfortunately, this was not the case. As Newton postulated, with every action comes an equal and opposite reaction. Often the more jarring the action, the more extreme the reaction. One such reaction was the sharp increase in violent firearm injury in our urban communities.

In early March, when it became clear that this virus needed to be taken seriously, governments across the country chose to shut down states, counties, and cities — and with that changed the patterns of violence. Now with the second wave in full force, unless rigorous violence prevention measures can counteract the impact of economic instability and social isolation, we may see gun violence increase once more.

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In preparing for the next health crisis — as well as adapting to the ongoing one — public health officials should plan to mitigate unintended impacts on specific populations. We found increases in gunshot wounds that disproportionately affected young, Black males, the urban demographic already overrepresented across decades of inner-city firearm-related intentional injury. At the same time, it is this very urban subpopulation that also appears to be at greater risk of COVID-19 infection and mortality.

Firearm violence impacts 25,000 young Americans per year, about half of whom die. It is unacceptable that one public health intervention should drive another public health crisis. Gun violence must not be an afterthought. As a second round of lockdowns begins, we must move forward in such a way that all Americans are safe. We cannot allow one pandemic to worsen, in order to treat another one.

Hatem Abdallah is an MD candidate at the University of Pennsylvania Perelman School of Medicine. He is currently leading a team of researchers investigating gun violence rates and demographics in Philadelphia. Elinore J. Kaufman, MD MSHP, is an assistant professor of surgery at the University of Pennsylvania. She specializes in trauma surgery, surgical critical care, and emergency surgery.

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