In his account of the 1348 plague outbreak in Florence, Italian author Giovanni Boccaccio described the deaths of two pigs who had been exposed to the clothes of a plague victim. He explained:
One day […] the rags of a pauper who had died from the disease were thrown into the street, where they attracted the attention of two pigs. In their wonted fashion, the pigs first of all gave the rags a thorough mauling with their snouts after which they took them between their teeth and shook them against their cheeks. And within a short time they began to writhe as though they had been poisoned, then they both dropped dead to the ground, spreadeagled upon the rags that had brought about their undoing. (Boccaccio 6-7)
Boccaccio’s anecdote is particularly vivid, but he was not the only person to mention that other-than-human animals died during the Black Death. The Franciscan Michele de Piazza recalled that the plague outbreak in Messina eradicated entire households—and it was not only humans who perished: “Not just one person in a house died, but the whole household, down to the cats and the livestock, followed their master to death” (Horrox 36-37). An account of plague in Padua remembered that “[j]ust as one infected sheep infects the whole flock, so one death within a household was always followed by the death of all the rest, right down to the dogs” (34). According to the Byzantine chronicler Nicepheros Gregoras, “The calamity did not destroy men only, but many animals living with and domesticated by men. I speak of dogs and horses and all the species of birds, even the rats that happened to live within the walls of the houses” (Bartsocas 395). And Gilles li Muisis, abbot of St. Giles at Tournai, wrote:
When one or two people had died in a house, the rest followed in a very short time, so that very often ten or more died in a single house; and in many houses the dogs and cats died as well. Thus no one, rich, middling or poor, was safe, but each one of them spent every day awaiting God’s will. (Horrox 54)
There are several ways of interpreting these accounts. Perhaps these authors were following textual precedents like Homer and Thucydides (Bartsocas 399). Even beyond any adherence to specific textual traditions, these reports of animal deaths have evident rhetorical functions. They emphasize the universality and inescapability of plague. Li Muisis’s statement that “no one” (regardless of wealth or even species) was safe illustrates this particularly clearly.
That being said, it is very plausible that at least some of these comments are recollections of actual animal deaths from plague. Certainly, Gregoras’s assertion that rats died from the disease is reasonable (Varlik 27). Plague spreads through rodent host populations via Y. pestis-infected fleas, who can shift to other animals once the original host population is depleted. And, although plague is primarily a disease of rodents, the modern strain of Y. pestis infects numerous animals—according to one study, 341 mammal species (273 of them rodents) and three wild bird species in total (Dubyanskiy and Yeszhanov). This includes domestic dogs and cats (Gage et al.; Nichols et al.; Oyston and Williamson; Schaffer et al.).
Why is medieval people’s inclusion of animal deaths in their descriptions of plague significant? For one, these reports enable us to take account of the Black Death’s scope (or at least its perceived scope, if these authors were wrong in attributing these animals’ deaths to plague) and provide potential insight into plague’s transmission during the Black Death and subsequent outbreaks. They also shed light on historical understandings of disease. Medieval people believed that plague could affect both humans and other animals. The reasons for this belief need to be explored further. For instance, it could have stemmed from observations of the disease’s behavior, or simply a presupposition that animals were community members who would naturally be affected by a major event like the Black Death.
Moreover, some of these accounts—Boccaccio’s most strikingly—record a human-to-animal path of disease transmission, inverting the more typical modern focus (Stoppino 99). Much modern scholarship is concerned with the spread of diseases from animals to humans. Recent work that rightly stresses the importance of ecology in understanding the history of plague mostly limits animals’ roles to that of disease transmitters (Campbell; Green; McCormick; Varlik). Less attention has been paid to animals as beings who could be affected by plague outbreaks alongside humans. But, for at least some medieval observers, they were exactly that.
Last but not least, other-than-human animals must be recognized as participants in history whose lives and deaths matter. This is true even from a strictly anthropocentric perspective. For humans, animal deaths—especially those of companion or working animals—can be traumatic and have emotional, economic, and other repercussions. And this is not to mention the ways in which plague outbreaks could have impacted relations between humans and animals more generally. For this reason and those mentioned above, animals need to be included in histories of plague—and other diseases—as more than agents of disease transmission to humans.
Image: “Vom dem sterben oder pestilentz dieseer weit tobt und weret,” woodcut from Francesco Petrarca, Von der Artzney bayder Glück, des guten und widerwertigen (Augsburg, 1532). Via Wikimedia Commons.
Bartsocas, Christos S. “Two Fourteenth Century Greek Descriptions of the “Black Death.”” J Hist Med Allied Sci, vol. 21, no. 4, 1966, pp. 394-400.
Boccaccio, Giovanni. The Decameron. 2nd ed., translated by G. H. McWilliam, Penguin, 1995.
Campbell, Bruce M. S. The Great Transition: Climate, Disease and Society in the Late Medieval World. Cambridge UP, 2016.
Dubyanskiy, Vladimir M., and Aidyn B. Yeszhanov. “Ecology of Yersinia pestis and the Epidemiology of Plague.” Yersinia pestis: Retrospective and Perspective, edited by Ruifu Yang and Andrey Anisimov, Springer, 2016, pp. 101-70.
Gage, Kenneth L., et al. “Cases of Cat-Associated Human Plague in the Western US, 1977-1998.” Clin Infect Dis, vol. 30, no. 6, 2000, pp. 893-900.
Green, Monica H. “Taking “Pandemic” Seriously: Making the Black Death Global.” Pandemic Disease in the Medieval World: Rethinking the Black Death, edited by Green, ARC Medieval Press, 2014, pp. 27-61.
Horrox, Rosemary, editor and translator. The Black Death. Manchester UP, 1994.
McCormick, Michael. “Rats, Communications, and Plague: Toward an Ecological History.” J Interdiscip Hist, vol. 34, no. 1, 2003, pp. 1-25.
Nichols, Megin C., et al. “Yersinia pestis infection in dogs: 62 cases (2003-2011).” J Am Vet Med Assoc, vol. 244, no. 10, 2014, pp. 1176-80.
Oyston, Petra C. F., and Diane Williamson. “Plague: Infections of Companion Animals and Opportunities for Intervention.” Animals, vol. 2011, no. 1, 2011, pp. 242-55.
Schaffer, Paula A., et al. “Delayed diagnosis of fatal pneumonic canine plague: clinical and pathologic features in two naturally infected Colorado dogs.” BMC Vet Res, vol. 16, 2020, pp. 1-8.
Stoppino, Eleanora. “Contamination, contagion and the animal function in Boccaccio’s Decameron.” Critica del testo vol. XVII, no. 3, 2014, pp. 93-114.
Varlik, Nükhet. Plague and Empire in the Early Modern Mediterranean World. Cambridge UP, 2015.