Tetanus vaccination is associated with decreased incidence of Parkinson’s disease and slower progression

Parkinson’s disease (PD) is characterized by progressive neurodegeneration in the autonomic and central nervous systems, manifesting with hallmark symptoms of rest tremor and bradykinesia. Its etiology remains poorly understood, and currently available treatments do not halt disease progression. Here we analyze the impact of vaccination and medication purchase on PD occurrence and disease severity in a national health provider, employing a novel machine learning method. We show that anti-tetanus vaccination significantly reduces PD occurrence, and that both the rate and severity of PD are strongly associated with the time elapsed since last vaccination. These results, which suggest that C. Tetani toxin is involved in PD pathology, are reinforced by findings that antimicrobial treatments that affect Clostridium species are associated with significant changes in disease severity. Tetanus vaccination and clostridium eradication are promising strategies to prevent PD and slow its progression, pending controlled trials. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement Funding: This study was funded internally by Leumit Health Services. ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: The Institutional Review Board (IRB) of Leumit Health Services gave ethical approval for this work (LEU-0001-24), with a waiver of informed consent, since data were analyzed retrospectively and anonymously. I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes Access to patients data is limited to researchers approved by the Institutional Review Board.