There was no effective treatment for the disease. Medieval medicine was basically a mixture of the ancient “four humors” theory and the astrological formulations of the Arabic physicians of the end of the first millennium. According to the Arab treatises, certain planetary alignments could foster illness by creating miasmas, or clouds of noxious air. In the judgment of many of the fourteenth century’s best minds, that was the cause of the Black Death. Some cities took public-health measures—mainly, quarantines. People were advised to avoid pore-opening activities (bathing, exercise, sex), so as to prevent the miasma from penetrating their skin.
The New Yorker reviewer thinks this new plague book is too padded, and recommends Norman Cantor’s 2001 “In the Wake of the Plague: The Black Death and the World It Made” instead. Cantor's book is better, we're told, because instead of wallowing in grim descriptions of buboes, it talks about the social and political consequences of living in a world suddenly bereft of one third of its inhabitants. Law students may like to know that "the most enthralling chapter has to do with property law."
In the course of their quarrels, the gentry and the nobility put aside old codes of civility, and that development, together with certain very striking national events—notably the ouster and probable murder of Richard II by Henry Bolingbroke, at the end of the century—created what Cantor calls a “new dark age of bad behavior.” The modern conviction “that unrestrained greed is good” was born. The new property legislation controlled it but also fostered it, by encouraging people to do whatever the law would let them get away with.