A lot of nonfiction books feel inevitable. Someone was bound to write them. If Walter Isaacson hadn’t written the definitive biography of Steve Jobs, someone else would have. But there are some nonfiction books whose very concept would be unthinkable without the peculiar interests and intelligence of their author. Books that are as strikingly unique as the person who writes them. Books like On Immunity by Eula Biss.

The unlikely premise of On Immunity is that vaccination—yes, like the shots you received when you were a kid—is the key to understanding all kinds of cultural and ethical issues, like public health, citizenship, motherhood, immigration, even the Revolutionary War and Count Dracula.

Biss starts small, with her own pregnancy, a germ of a child growing inside her. She writes powerfully about the physical trauma of childbirth and the madness of trying to protect a child from all sorts of dangers, seen and unseen.

Immediately after my son’s birth, in an otherwise complicated delivery, my uterus inverted, bursting capillaries and spilling blood… I woke up disoriented, shivering violently under a pile of heated blankets… I was too weak to move much, but when I tried I discovered that my body was lashed with tubes and wires—I had an IV in each arm, a catheter down my leg, monitors on my chest, and an oxygen mask on my face.

But this is no memoir. Biss only provides her personal story as background: “My pregnancy, like every pregnancy, had primed me for the understanding that my body was not mine alone and that its boundaries were more porous than I had been led to believe.” Her real aim is to explore the science, policies, and metaphors that govern our understanding of illness and our relationships with our bodies. Biss takes every available approach, from interviewing her own family (her father is a charming doctor, her sister is a Kantian philosopher), to arguing against idiotic public statements by Jenny McCarthy and Ask Dr. Sears, to offering a close reading of the myths of Achilles and Narcissus. Her mind is everywhere at once, and her conclusions are subtle, deeply felt, and convincing.

In the book’s most significant passages, Biss draws a clear line from our bodies, with all of their bacteria and viruses and beneficial parasites, to our society, with its complex vulnerabilities and interdependencies. She shows how it is impossible to separate our individual health from the health of our neighbors and our surroundings.

If we do not yet know exactly what the presence of a vast range of chemicals in umbilical cord blood and breast milk might mean for the future of our children’s health, we do at least know that we are no cleaner, even at birth, than our environment at large. We are already polluted. We have more microorganisms in our guts than we have cells in our bodies—are, in other words, continuous with everything here on earth. Including, and especially, each other.

Illness and metaphor is territory that Susan Sontag famously explored, and with her chilly rationality Biss is frequently reminiscent of Joan Didion. But I suspect she learned a lot from John McPhee, too—her dogged investigation of the mechanics of disease has his no-fuss authority and plainspoken appeal. So yeah, she’s a combination of all the greatest nonfiction writers of the 20^th century.

I have complaints about this book. The organization—it’s made up of short, unnamed chapters that elaborate on each other—is unwieldy and leads to repetition. Despite frequent attempts, Biss never manages to convince me that her detailed analysis of Dracula—from the original novel to the Twilight craze—belongs in this book. And yet my complaints are totally inconsequential in the face of what Biss has accomplished, which is to outline a way for us to reorient our science, our public policy, and our selves around a shared understanding of the common good.

And when I think about how unlikely it is that this book exists in the first place—how un-inevitable this particular book is—I feel incredibly, microscopically lucky that Biss, and On Immunity, live.

– Brian Hurley is Books Editor at The Rumpus, Founder of Fiction Advocate, and Curator of the Critical Hit Awards.