Recent research suggests that amyloid-beta proteins associated with Alzheimer disease can be transmitted via medical and surgical procedures person-to-person
This evidence presents the initial studies on Creutzfeldt-Jakob disease as a consequence of treatment with cadaver-derived human growth factor hormone. Post-mortem brain tissue revealed that patients had developed cerebral amyloid deposition in addition to the lesions due to mad cow disease. Clearly, those individuals will never developed Alzheimer because of absence of lifetime to do so. A study of material used for hormone growth extracted from human brain tissue and conserved for more than 30 years, showed in some batches substantial levels of amyloid and tau protein – both associated with neurofibrillary tangles and Alzheimer’s disease. Intra cerebral injections of amyloid proteins isolated from Alzheimer patients were able to induce Alzheimer-like disease in mice.
The author considers that there is enough evidence to support that Alzheimer’s disease can be transmitted to persons by contaminated instruments. This finding implies a potential risk for neurosurgical procedures or for the use of biological materials from central nervous system. Fortunately, there is no evidence on possible transmission of the disease by blood transfusions, and also no findings that Alzheimer’s disease could be contagious.
In a recent published case report including 4 patients with cerebral amyloid angiopathy who underwent neurosurgical procedures 2 or 3 decades earlier again neurofibrillary tangles were found. Biological material should be screened for the prion-like forms of proteins that can misfold such as beta amyloid, tau and alpha synuyclein, before used in humans.
Editor’s note: classical sterilization does not inactivate prions completely; the temperature for inactivation is higher.
Hampton T. Studies further support transmisibility of Alzheimer disease-associated proteins. JAMA. 2019;321(13):1243-44. https://doi.org/10.1001/jama.2019.2650.