Sally Satel is a visiting professor of psychiatry at Columbia University’s Vagelos College of Physicians and Surgeons and a resident scholar at the American Enterprise Institute.

In March 2006, a distant friend — now a dear one — gave me one of her kidneys. Unfortunately, that kidney had a short run, lasting only about 10 years when it should have worked for about twice that long. And so another earthbound saint, a friend who watched me struggle to find the first donor, offered me one of hers.

Two times in the space of a decade, then, I became the beneficiary of one of the greatest acts of human altruism: living organ donation.

Now, I find myself dependent on others yet again. This time, my health relies on people to get vaccinated against the coronavirus.

As a transplant recipient, I am one of the immunologically unlucky: those who derive insufficient or no protective immunity from vaccinations. We organ recipients take medications — typically anti-metabolites — that suppress our immune systems, specifically, the function of the body’s B cells, which are responsible for generating antibodies. These drugs are necessary to prevent the body from attacking implanted organs, thus blocking organ rejection.

But this means that many of us produce no detectable defenses against covid-19. A recent report in the Journal of the American Medical Association by a team at Johns Hopkins found that among organ recipients, only 8 percent of those on an anti-metabolite mounted a respectable antibody response after the first and second doses of both the Moderna and Pfizer-BioNTech vaccines, and 57 percent had no detectable response at all.

Our poorly performing immune systems also compound our vulnerability in that if we do get infected, we are at enhanced risk of developing severe covid-19 symptoms.

Fortunately, some patients with autoimmune diseases appear to have more robust responses to the vaccine, and it is possible that other components of the immune system might mobilize against covid-19 in unanticipated ways. Plus, a third shot may help people who are “severely immunocompromised,” as the French health ministry recommended last month. Researchers at Johns Hopkins are studying its impact, too.

Still, there are unanswered questions, which is why experts are telling us nonresponders and poor responders to assume we are unprotected and use the same precautions that everyone was instructed to exercise before the arrival of the vaccines.

I intend to wear masks in crowded indoor places and hope that, if I get covid-19, I will benefit from doctors’ steep learning curves in treating the infection. As part of my work as a psychiatrist, I have resumed seeing patients at a methadone clinic. I elect to take the risk. Perhaps I will come to regret writing that sentence.

Others will be more restrained. A 71-year-old double lung transplant patient in Austin told NPR that she will not travel to see her family in Europe, whom she has not seen in two years. David Goldstein, a liver transplant recipient, similarly lamented in an op-ed for Medpage Today that he has to “remain in my burrow when I had so hoped to be able to escape.”

Transplant patients know the extraordinary kindness of strangers. About one-fourth of kidney recipients receive the organ from a magnificent friend or loved one, sometimes even an anonymous donor who is moved to save a life. The remaining kidneys, nearly all livers and lungs, and all hearts come mostly from young, healthy people whose sudden and sometimes violent deaths gutted their families. Yet those families could see the blessing in giving.

When my first donor described her reason for giving me a kidney (she had heard secondhand about my donor search and could have easily said nothing to me about it), she invoked one of her intellectual heroes, the Scottish philosopher Adam Smith. In “The Theory of Moral Sentiments,” Smith wrote, “As we have no immediate experience of what other men feel, we can form no idea of the manner in which they are affected, but by conceiving what we ourselves should feel in the like situation.”

The reaction Smith names is immediate and selfless, not calculated to maximize the general welfare of a population, but rather aimed at one suffering person. This sympathy, Smith wrote, is the foundation of altruism.

The altruism of getting vaccinated is a more diffuse kind of sentiment. It is an act of generosity — a “love thy neighbor,” communitarian ethic — aimed at the nameless and faceless: me and my immunologically challenged cohort.

It goes beyond the standard public health imperative of utilitarianism — maximizing good consequences for all of society by helping attain herd immunity — and the rational self-interest of protecting the person getting vaccinated.

This is my appeal to the vaccine hesitant: If you think you won’t catch the virus or that the symptoms won’t be devastating if you do, statistically speaking, you are probably right. Yet taking action to keep yourself from spreading it to the vulnerable would be a great act of charity. Yes, it’s a bit of a sacrifice, but it’s not like we are asking you for a kidney.

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