Parkinson Disease: Taubenberger JK

McCall S, Vilensky JA, Gilman S, Taubenberger JK. · Department of Clinical Pathology, US Army Medical Research Institute of Infectious Diseases, Fort Detrick, Maryland, USA. · J Neurovirol. · Pubmed #18569452 No free full text.

Abstract: Since encephalitis lethargica's (EL) prevalence in the 1920s, epidemiologic and clinical debate has persisted over whether EL was caused by, potentiated by, or merely coincident with the Spanish influenza pandemic. Epidemiologic analyses generally suggest that the disorders were coincidental. Beginning in the 1970s, modern experiments on archival brain samples mainly failed to confirm a direct relationship between influenza and EL. These experimental studies have technical limitations, e.g., the appropriateness of antibodies, polymerase chain reaction (PCR) primers and controls, and the extreme paucity and age of available material. These factors render the case against influenza less decisive than currently perceived. Nevertheless, there is little direct evidence supporting influenza in the etiology of EL. Almost 100 years after the EL epidemic, its etiology remains enigmatic, raising the possibility of a recurrence of EL in a future influenza pandemic.

Reid AH, McCall S, Henry JM, Taubenberger JK. · Department of Cellular Pathology and Genetics, Armed Forces Institute of Pathology, Washington, DC, USA. · J Neuropathol Exp Neurol. · Pubmed #11444794 No free full text.

Abstract: Encephalitis lethargica (EL) was a complex and mysterious disease that appeared around the same time as the great influenza pandemic of 1918. The contemporaneous relationship of the 2 diseases led to speculation that they were causally related. Contemporary and subsequent observers conjectured that the influenza virus, directly responsible for the deaths of more than 20 million people, might also have been the cause of EL. A review of the extensive literature by observers of the EL epidemic suggests that most contemporary clinicians, epidemiologists, and pathologists rejected the theory that the 1918 influenza virus was directly responsible for EL. Disappearance of the acute form of EL during the 1920s has precluded direct study of this entity. However, modern molecular biology techniques have made it possible to examine archival tissue samples from victims of the 1918 pandemic in order to detect and study the genetic structure of the killer virus. Similarly, tissue samples from EL victims can now be examined for evidence of infection by the 1918 influenza virus.

McCall S, Henry JM, Reid AH, Taubenberger JK. · FDepartment of Cellular Pathology and Genetics, Armed Forces Institute of Pathology, Washington, DC, USA. · J Neuropathol Exp Neurol. · Pubmed #11444798 No free full text.

Abstract: Encephalitis lethargica (EL) was a mysterious epidemic. temporally associated with the 1918 Spanish influenza pandemic. Numerous symptoms characterized this disease, including headache, diplopia, fever, fatal coma, delirium, oculogyric crisis, lethargy, catatonia, and psychiatric symptoms. Many patients who initially recovered subsequently developed profound, chronic parkinsonism. The etiologic association of influenza with EL is controversial. Five acute EL autopsies and more than 70 postencephalitic parkinsonian autopsies were available in the Armed Forces Institute of Pathology (AFIP) tissue repository. Two of these 5 acute EL cases had histopathologic changes consistent with that diagnosis. The remaining 3 cases were classified as possible acute EL cases as the autopsy material was insufficient for detailed histopathologic examination. RNA lysates were prepared from 29 CNS autopsy tissue blocks from the 5 acute cases and 9 lysates from blocks containing substantia nigra from 2 postencephalitic cases. RNA recovery was assessed by amplification of beta-2-microglobulin mRNA and 65% of the tissue blocks contained amplifiable RNA. Reverse transcription-polymerase chain reaction (RT-PCR) for influenza matrix and nucleoprotein genes was negative in all cases. Thus, it is unlikely that the 1918 influenza virus was neurotropic and directly responsible for the outbreak of EL.