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Comments Regarding Selected Causes of Death Recorded by Pioneers, 1839–48

Ague (Latin acuta, “sharp” or “acute”): Acute attacks of chills and fever. In the mid-nineteenth century, the term “ague” usually described malaria. Other terms such as “chill fever,” “recurrent chills,” or “bilious fever” also were descriptors of malaria. Malaria-related deaths usually occurred one to three months after a person had been bitten by a mosquito carrying virulent plasmodium parasites. The disease is commonly associated with marked malaise, a lack of energy, and a sense of depression. These three symptoms by themselves were commonly referred to as ague.

Apoplexy (Greek apoplēssein, “to strike”): This refers to a stroke, often due to a hemorrhage or blood clot in an organ, usually the brain. It can cause various symptoms including weakness or palsy, altered sensation, and problems with vision, speech, or walking.

Bilious fever (Latin bilis, “bile”): Refers to fever associated with excessive bile or bilirubin in the blood stream and tissues, causing jaundice (a yellow color in the skin or sclera of the eye). The most common cause was malaria. Viral hepatitis and bacterial infections of the blood stream (sepsis) may have caused a few of the deaths reported as bilious fever.

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Malaria (Italian mala + aria, “bad air”): A disease thought to be due to bad air in the mid-nineteenth century. It actually was caused by the bite of an anopheles mosquito transmitting plasmodium parasites which entered the victim’s red blood cells and destroyed many of them. There are four types of malaria parasites, Plasmodium falciparum being the one that is usually responsible for death. The disease is typically manifested by severe recurrent chills and fever, often with jaundice, sweating, and fatigue. Death, when it occurs, usually comes one to three months after exposure to mosquitoes carrying the parasite. Mosquitoes were prevalent mainly from July until the first frost in Nauvoo and Winter Quarters. Deaths attributed to ague were largely due to malaria in Nauvoo and Winter Quarters.