The most common prion disease in humans is the Creutzfeldt-Jakob disease or the CJD. Its variant form has an incubation period of ten years, with severe symptoms often progressing rapidly. With no treatments or vaccines for prion diseases, it proves to be a heavily painful and fatal sickness.

In May 2010, lab worker Émilie Jaumain accidentally stabbed herself with forceps that handled prion-infected brain samples from mice. 7.5 years later, Jaumain’s prion disease symptoms started as a burning pain in her neck, eventually leading to her death in 2019. 

What are Prions? How Are They Related to Diseases?

According to Ars Technica’s article regarding the recent prion-disease-related death of a lab worker in France, the clumping of misfolded prion proteins with normal prion proteins result in prion diseases.

Prion diseases, or transmissible spongiform encephalopathies, have many outward symptoms that progress rapidly. The medical manifestations include painful nerve damage, dementia, confusion, psychiatric symptoms, difficulty in moving and speaking, and hallucinations.

Prions are misfolded, misshapen forms of normal proteins, called prion proteins, that are commonly found in human and other animal cells. What prion proteins do normally is still unclear, but they’re readily found in the human brain. When a misfolded prion enters the mix, it can corrupt the normal prion proteins around them, prompting them to misfold as well, clump together, and corrupt others.

Beth Mole, Ars Technica

The Creutzfeldt-Jakob disease, or the CJD, is the most common prion disease. The CJD has a classic form and a variant form. The classic kind of the Creutzfeldt-Jakob disease is sporadic in 85% of its patients and 5% to 15% of cases possibly hereditary with links to family history. Contrarily, CJD’s variant form is infectious, commonly correlated with mad cow disease. An individual acquires variant CJD by ingesting prion-contaminated meat. Variant CJD can also develop in prion-infected wounds and possibly through aerosols, as proven through mice. Once exposure happens, the incubation period of ten years follows after the manifestation of symptoms. (Source: Ars Technica) 

The Case of Émilie Jaumain

Variant CJD was the primary suspect of French lab worker Émilie Jaumain’s 2019 prion disease. In 2010, Émilie Jaumain worked as a lab worker for France’s National Research Institute for Agriculture, Food, and Environment. When May 2010 came, Jaumain accidentally stabbed her thumb with forceps that held frozen, prion-infected brain samples from mice while working in a prion lab. The forceps penetrated through a double-layer of latex gloves, drawing blood.

Armel Houel, Jaumain’s widower, stated that the former lab technician immediately worried about her health and mentioned her situation to every doctor she encountered.

In a case report of Jaumain’s disease published in The New England Journal of Medicine, Jaumain’s symptoms started 7.5 years after the accident. Her symptoms began with burning pain in her neck and right shoulder, immediately worsening and spreading to the right half of her body in six months. In early 2019, Jaumain already had anxiety, depression, memory impairment, and visual hallucinations. Prior to her death in June 2019, Jaumain became incapable of moving and speaking. (Source: Ars Technica)