In 1869, essayist W.E.H. Lecky wrote optimistically about the ‘expanding circle’ of human morality — at first including “merely the family, soon … a class, then a nation, then a coalition of nations, then all humanity.” (Not unlike the spread of a pandemic, I hear you say.)

Covid-19 has reshaped the world, causing untold suffering and upending the norms we took for granted. When the history books are written, I feel that the most remarkable part of the story will prove to be the spectacular research and manufacturing success that has granted the world multiple highly effective vaccines against Covid-19, a pathogen that did not exist this time two years ago. This is incredible. At Harvard, vaccines are the reasons why students are back on campus at last. In Ireland, where I’m from (as was Lecky, as it happens), the roll-out is proving hugely successful.

However, what remains to be determined is whether this particular chapter of future history books will feature a deeply depressing footnote — namely, about vaccine stockpiling.

As of Sept. 11, 2021, the United States has administered 112.8 doses per 100 people in its population; the European Union, 121.8 doses; and Africa, just 8.7 doses. At the outset of the pandemic, rich nations understandably but selfishly rushed to protect their populations and preemptively bought many more vaccines than needed. We now are faced with the appalling prospect of discarding billions of unused and expired vaccine doses. As reported by the British Medical Journal, the U.S. is projected to have 1.8 billion surplus doses due to expire by the end of 2022. The E.U. is on course for a surplus of 2.8 billion in the same period. Greed has been compounded by unexpectedly low uptake in certain communities and highly cautious three-month expiry dates for several jabs, resulting in a stunningly inequitable global distribution of these precious vaccines.

This is gravely wrong. In particular, it is grotesquely unethical that rich countries continue to procure supplies to commence large-scale booster campaigns for already-vaccinated, healthy adults, while medically vulnerable people and frontline healthcare workers contract and die from Covid-19 in large numbers in the rest of the world. As World Health Organization Director-General Dr. Tedros Adhanom Ghebreyesus has declared, “We cannot accept countries that have already used most of the global supply of vaccines using even more of it.” Dr. Ghebreyesus has called for a moratorium on booster shots.

In the months preceding my move to Boston, I volunteered as a doctor with a medical charity in Tanzania. Covid-19 was everywhere. Patients and staff alike were contracting it, though deficiencies in testing meant the number of cases was impossible to quantify. I remember a colleague telling me in a quiet voice that several doctors had recently died in another region’s hospital. I was fully vaccinated. He was not. I felt ashamed.

In the U.S., the Biden administration has made some statements of intent to address this inequity, such as a plan to donate over half a billion vaccine doses in the coming year. However, the pace of delivery since that announcement suggests that target will not be met — particularly as a federal plan to offer booster shots to healthy adults is unveiled. The cynic in me wonders if such pledges are mainly concerned with keeping up with China.

For two reasons, this injustice should trouble Harvard students. Firstly, as members of a prestigious and truly international community, Harvard students should appreciate better than most that the gap between domestic concerns and global issues has never been narrower. The urgency of this truly global problem speaks for itself.

Secondly, on a more self-interested basis, we must realize that vaccine stockpiling is not only deeply wrong, but self-defeating. Gains made in this pandemic — exemplified by Harvard’s campus coming to life with the arrival of students for in-person teaching — are fragile, reversible, and inextricable from global instability. Covid-19 transmission rages unchecked among billions of unvaccinated people in poor regions of the world and these are almost precisely the conditions most conducive to the emergence of an escape variant capable of evading the defenses of our current vaccines, landing us back at square one.

So — as Albert Camus’s protagonist Dr. Rieux exhorts the townspeople of Oran — the only way to fight the plague is with decency. The only way to eliminate the threat of Covid-19 anywhere will be to eliminate it everywhere. For reasons of both ethics and self-interest, we cannot permit billions of people to be left behind. If you agree, contact your local representative and tell them as much. Even better, donate something to Gavi and the COVAX initiative.

In this strange world of mask-wearing and elbow-bumping, we have realized that the welfare of those around us, even those we do not know, is inextricable from our own. Of course, as Lecky would remind us, this was true all along.

Domhnall McGlacken-Byrne is a master’s student at Harvard T.H. Chan School of Public Health.