I recently watched the 2011 movie version of Jane Eyre. Since it has been about 20 years since I read the novel in high school some of the plot details had become somewhat hazy (pun intended for the really nerdy), including the multiple instances in which the infectious disease typhus is mentioned.
In the novel, typhus runs rampant at Lowood, the boarding school to which Jane is sent, and Jane's wicked aunt falsely reports Jane's death from typhus to another relative. Jane herself never contracts the disease.
Typhus, not to be confused with typhoid, is caused by Rickettsia prowazekii and carried by the human body louse. The word is derived from the Greek work typhos, which means hazy or smokey, a reference to the dazed mental state characteristic of the disease. Because of the relationship between cleanliness, the body louse, and the typhus microbe, this disease has a special place in history--one of my favorite aspects of infectious disease.
Epidemic typhus was considered a major health threat for most of history and remains so for certain parts of the world today. The use of epidemic typhus as a bioweapon is also a concern.
Probably the greatest role typhus has taken on is in thwarting Napolean's invasion of Russia, the subject of The Illustrious Dead. Typhus was also responsible for the death of President Franklin Pierce's son. Today, the disease occurs in situations enticing to lice such as in refugee camps.
One of the other reasons I like typhus is because one of its foremost researchers was Hans Zinsser, who delivered my favorite quote regarding infectious disease, capturing the entire allure of the discipline:
Infectious disease is one of the few genuine adventures left in the world. The dragons are all dead and the lance grows rusty in the chimney corner. ... About the only sporting proposition that remains unimpaired by the relentless domestication of a once free-living human species is the war against those ferocious little fellow creatures, which lurk in dark corners and stalk us in the bodies of rats, mice and all kinds of domestic animals; which fly and crawl with the insects, and waylay us in our food and drink and even in our love.