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Infection in humans
Can humans become infected with BSE?
Creutzfeldt-Jakob disease (CJD)
Creutzfeldt-Jakob disease (CJD) is known as a TSE known to occur in humans.
The conventional known forms of CJD include sporadic (90% of cases), familial (5-10%), and iatrogenic: (less than 5%), but a form called variant CJD (vCJD), which exhibits a different pathology from the above, has also been reported.
vCJD is believed to be caused by the same prions as BSE, with the disease being characterized by the relatively young age of sufferers and the long clinical course of the infection. No cure has yet been found for vCJD.
Preliminary calculations prior to BSE measures were taken in Japan indicate that the 0.1-0.9 people will contract BSE and develop vCJD in the entirety of the country in the future (out of a population of approximately 120 million). In Japan, a single case of vCJD has been confirmed (occurring in 2001); however, experts believe there is a strong likelihood this person contracted the disease while living in the United Kingdom.
Sources of infection in humans
So, how do humans become infected with BSE?
The most prominent theory for how people become infected with BSE is by eating food contaminated with abnormal prions. The abnormal prions which cause BSE do not exist in uniform quantity throughout an infected animal’s body but rather are concentrated in specific tissues, particularly the brain, spinal cord, and parts connected to the central nervous system. Thus, the proper removal and disposal of these parts are believed to ensure the safety of all other parts of the cow (meat, organs, milk, milk products, and gelatin and collagen collected from the hide).