The ick factor is high—20-foot tapeworms, skin nodules filled with writhing worms, etc.—but for parasitologists, the fellow travelers chronicled in this illuminating book command respect for the artful ways they have managed cohabitation since the dawn of life.
Despommier (Emeritus, Public Health and Microbiology/Columbia Univ.; The Vertical Farm: Feeding the World in the 21st Century, 2010, etc.) writes that his prime interests are not short-lived protozoans like the malaria parasite, deadly though it is. What fascinates him are parasites able to survive in a host for years, inflicting slow but inexorable harm. His specialty has been a species of nematode that causes trichinosis. Once the larvae are ingested, they mature, mate, produce new larvae in the gut and then move out to muscle tissue. There, they fashion a “nurse cell,” a fortress that protects the larvae as they grow to the infective stage. Such complex life cycles are typical of parasites and are delineated by Despommier in chapters devoted to hookworm, trypanosomes, lymphatic filariae, tapeworms and other scourges. Some parasites don’t have to be eaten or gain entry through a cut or insect bite; they can sneak in along a hair follicle. Others elude immune capture by secretions that suppress immunity or by changing their surface antigens. Despommier highlights these parasite tricks, and he discusses voluntary infection with whipworms to treat autoimmune disease by quieting an overactive immune system. Yes, the infection helps, but eventually, patients mount an immune response to kill the worms, allowing their autoimmune disease to return—all the more reason to search for the key molecules involved. Sadly, parasitic diseases remain highly prevalent, albeit with an occasional success story.
Despommier is an excellent popularizer, lacing his accounts of our invaders’ ingenuity with history and anecdotes that underscore how grateful a modern society should be for clean drinking water and sanitary facilities.