Well, Laura Ingalls Wilder of "Little House" fame attributed her sister Mary's blindness to scarlet fever.
I, for sure, took this diagnosis at face value. Why wouldn't I?
However, as it turns out, Mary probably suffered from viral meningoencephalitis. In a recent Pediatrics article, Dr. Beth Tarini and some colleagues reported their reassessment of Mary's condition, having spent years pouring over Laura's letters and other documents which alluded to Mary's symptoms.
Even though Mary had indeed contracted the disease as a child--in both the TV show and the book, we were infomed that "her eyes had been weakened as a child"--other symptoms were more telling. She went blind as a teenager, in 1879. Half her face had apparently been paralyzed, along with her eye muscles. Most telling of all, Laura later refers to Mary's "spinal sickness" in a letter to her daughter Rose. In 1881, Mary went to the Iowa Braille and Sight Saving School.
Was the assumption of scarlet fever simply a misdiagnosis?
In the case of Helen Keller, this is quite possible. In the case of Mary, no. Dr. Tarini's team concluded that the family was aware of Mary's true disease, but that Laura had deliberately obscured the nature of her sister's condition when she discussed it in her books.
Why would Laura have changed her sister's disease?
Dr. Tarini conjectured that scarlet fever, being a common malady, would have been more relatable to the author's audience. There's something to that hypothesis, for sure.
However, at the end of the nineteenth century, there was a real stigma associated with "brain fever," a catch-all term for neural sicknesses like meningoecephaliti and meningitis). After all, this was the era of both the rise of psychology and neurology, and the accompanying classification of mental disorders and illnesses. So Laura's rewriting of her sister's history was likely because scarlet fever was more palatable, not just more relatable.
Laura is certainly not the first person to hide her family's secrets, or to rewrite her narrative. The tragedy of her own husband--Almonzo--is another example of how she reconstructed her past.
But perhaps that's the greatest feat of a storyteller. Telling the story we want to hear, not what really happened. In this case, however, Laura's retelling has probably caused generations of people to associate scarlet fever with blindness, which is certainly incorrect.
Yet another reason to constantly question what we read; to question what we know to be true.
But what do you think?