A Rare Case of Occupational Exposure to Variant Creutzfeldt-Jakob Disease
A case report published in the New England Journal of Medicine described a laboratory technician who developed variant Creutzfeldt-Jakob disease (vCJD) approximately 7.5 years after a workplace accident involving exposure to infected laboratory material (Brandel et al., 2020).
Cattle
Variant CJD is a rare and fatal neurological disorder caused by prions, which are abnormally folded proteins that damage brain tissue. The disease is associated with bovine spongiform encephalopathy (BSE), commonly known as mad cow disease, which affects cattle.
Because occupational transmission of vCJD is extremely uncommon, this case attracted significant attention from researchers and public health officials (Brandel et al., 2020).
The Laboratory Accident
On May 30, 2010, a laboratory technician working in Jouy-en-Josas, France, accidentally cut herself while handling mice that had been experimentally infected with prions associated with variant Creutzfeldt-Jakob disease (Brandel et al., 2020).
The technician was wearing protective gloves at the time of the incident, but the gloves were torn during the accident. The wound was immediately disinfected and reported as a workplace injury (Brandel et al., 2020).
For several years after the exposure, no symptoms were reported.
However, approximately 7.5 years later, neurological symptoms began to appear (Brandel et al., 2020).
Symptoms Appeared Years After Exposure
According to the New England Journal of Medicine, the technician first experienced pain in her right shoulder and neck in November 2017 (Brandel et al., 2020).
Over the following months, the symptoms progressively worsened. Pain spread throughout the right side of her body, and by early 2019, she had developed hallucinations and memory problems (Brandel et al., 2020).
In April 2019, specialists at the National Reference Center for Creutzfeldt-Jakob Disease at Pitié-Salpêtrière Hospital confirmed the diagnosis of variant Creutzfeldt-Jakob disease (Brandel et al., 2020).
The patient died several months later at the age of 33 (Brandel et al., 2020).
Why Researchers Suspected Occupational Transmission
Researchers considered food-related exposure to be unlikely because the epidemiological timeline did not support recent dietary exposure (Brandel et al., 2020).
The investigators noted that the strain of prions used in the laboratory was compatible with the disease that later developed in the patient (Brandel et al., 2020).
Additionally, the incubation period observed in this case was consistent with previously documented cases of transmitted prion disease (Brandel et al., 2020).
Although researchers considered several possible explanations, they concluded that occupational exposure represented the most plausible source of infection because the characteristics of the patient’s disease matched the prion strain used in the laboratory (Brandel et al., 2020).
What Are Prions?
Prions are naturally occurring proteins found primarily in nervous tissue. Unlike bacteria and viruses, prions do not contain DNA or RNA (National Institute of Neurological Disorders and Stroke [NINDS], 2025).
Disease occurs when normal proteins become abnormally folded. These altered proteins can then induce neighboring proteins to change shape, creating a chain reaction that progressively damages brain tissue (NINDS, 2025).
What Are the Symptoms of Variant Creutzfeldt-Jakob Disease?
Symptoms of variant CJD usually develop gradually and worsen over time.
Common symptoms include:
- Persistent pain
- Memory problems
- Personality changes
- Hallucinations
- Depression
- Difficulty concentrating
- Problems with coordination and movement
- Sensory disturbances
Neurological deterioration becomes progressively more severe as abnormal prion proteins accumulate in the brain (NINDS, 2025).
How Common Is Occupational Transmission?
Occupational transmission of variant Creutzfeldt-Jakob disease is extremely rare (Centers for Disease Control and Prevention [CDC], 2024).
Historically, most cases of variant CJD have been linked to exposure to bovine spongiform encephalopathy through contaminated food products (CDC, 2024).
This case highlights the importance of strict laboratory safety procedures, including protective equipment, exposure reporting, decontamination protocols, and long-term medical surveillance.
Why This Case Matters
Although variant Creutzfeldt-Jakob disease remains exceptionally uncommon, this case demonstrates that accidental exposure to infectious biological material can have serious long-term consequences (Brandel et al., 2020).
The report also underscores the importance of maintaining rigorous biosafety standards when handling prion-infected material (CDC, 2024).
References
Brandel, J. P., Vlaicu, M. B., Culeux, A., Belondrade, M., Bougard, D., Grznarova, K., Denouel, A., Plu, I., Bouaziz-Amar, E., Seilhean, D., Levasseur, M., & Haïk, S. (2020). Variant Creutzfeldt–Jakob disease diagnosed 7.5 years after occupational exposure. The New England Journal of Medicine, 383(1), 83–85. https://doi.org/10.1056/NEJMc2000687
Centers for Disease Control and Prevention. (2024). Classic CJD versus variant CJD. https://www.cdc.gov/prions/cjd/occurrence-transmission.html
National Institute of Neurological Disorders and Stroke. (2025). Creutzfeldt-Jakob disease fact sheet. https://www.ninds.nih.gov/health-information/disorders/creutzfeldt-jakob-disease