Rats—the small rodent kind and the large human kind—figure prominently in Georg Letham: Physician and Murderer. Hordes of rats infest this novel, and they are nearly impossible to exterminate. Georg Letham, the narrator of this sprawling story, is a 40-year-old European physician with self-destructive tendencies and a deep affection for money. Although Letham prides himself on his ability to inspire trust, he is not trustworthy. By the end of the book, the twisted physician rediscovers his humanity and uncovers the epidemiology of yellow fever.

Letham’s life is full of contradictions. He admits to being lucky but gripes about his misfortune. He spends his nights either working in the laboratory or gambling. He is both a criminal and a scientist. Although his main interest is experimental bacteriology, Letham begins a private practice concentrating on surgery and gynecology. In hindsight, his exodus from research is a bad choice. He is not a people person: “Illness interested me, the ill did not.”

Letham’s tragic flaw is carelessness. While investigating scarlet fever, he transmits streptococcal sepsis to 2 surgical patients. He is unfaithful to his older and wealthy wife, and he later murders her by administering a deadly toxin. He is sloppy and leaves evidence—an empty vial and syringe—behind. He goes to trial, and his punishment for poisoning his wife is a life sentence of hard labor in a penal colony.

Meanwhile, yellow fever is wreaking havoc on the tropical island where Letham is sent for imprisonment. The mortality rate from the infection is as high as 55%, and the etiology and transmission of the disease are as yet unknown. Typhus, leprosy, tuberculosis, and malaria also vex the inhabitants of the island. In all, an appropriate environment for a physician-murderer who happens to have an interest in microbiology research. Letham is quickly put to work in a makeshift hospital set up in a former convent. A group of 5 persons including Letham, a fellow convict, 2 physician-scientists, and the prison chaplain (a priest with an “Amen” tattoo) set out to identify the cause of yellow fever and how to stop its spread. They intend to infect themselves with the disease. The men are willing to sacrifice their own lives (along with the lives of others) to find an answer: “Physicians have experimented on human beings from time to time for as long as medical science has existed. It has not been exactly the rule, but by no means the exception, either, that physicians have ventured to experiment on themselves.”

Their self-experimentation is “successful.” Letham contracts yellow fever and endures its terrible symptoms but survives. Others are not so fortunate: 2 men die as a result of the experiment. The scientists prove that the Stegomyia mosquito is the vector of transmission. The governor of the prison island authorizes a program to eradicate the mosquitoes, with the aim of eliminating yellow fever. Letham’s influential father pulls some strings to obtain clemency for his son, and in light of Letham’s sacrifice and service, the murderer receives a pardon. Although he must remain in exile on the island, he is allowed to ply his trade as a physician.

Medical ethics is a hot topic in this novel. Yet the story addresses several important issues beyond the proper behavior of physicians and the moral code of conduct for medical researchers: justice, punishment, altruism, the fear of illness, the joy of recovery, the ecstasy of being alive, and the absolute worth of a single human life. Slowly and painfully, the physician-murderer comes to understand the duty of a physician—which is first and foremost to provide solace for the patient.

The author, Ernst Weiss, has medical credentials. He served as a ship’s physician and as a military physician. He was a friend of Franz Kafka, a survivor of tuberculosis and attempted suicide. First published in German in 1931, the book is now available in an English translation. Although the first half of this marathon-like novel is often tough sledding, it finishes strong. Part medical detective story and part criminal confession, Georg Letham: Physician and Murderer is a long and risky read. From a literary standpoint, readers can expect a sizeable reward for their effort.