Meningitis: Controversies and Understanding Etiology of the Disease in the 19th Century

meningitis, and how accurately medical literature reflects these historical developments. Background. Bacteriological discoveries in the last quarter of the 19th century brought rapid progress in understanding various infections including meningitis. Significant challenges and confusion surrounded early reports that implicated Salmonella species in producing meningeal inflammation. These studies escaped historical analysis. Methods. As part of this study, 65 original articles and numerous other sources that discuss 26 etiology of bacterial meningitis in the last quarter of the 19th century were critically reviewed. In addition, more than 50 case reports and reviews of the infection published after 1960 were investigated for historical accuracy. Results. Not a single article since 1960 honored German physicians Neumann and Schaeffer who described the earliest known case of typhoid meningitis with solid bacteriological evidence in 1887. Instead, a remark of a prominent Austrian pathologist Ghon made in 1907 is inaccurately referenced as the first report of Salmonella meningitis. The 1887 paper of Neumann and Schaeffer prompted reassessment of then existing erroneous assumptions about typhoid bacilli such as their inability to produce pus and cause infection without Peyer’s patches. It also promoted search for reliable methods in differentiation among strains of Salmonellae and Coli bacteria. Conclusion. Controversies sparked by early studies of typhoid meningitis stimulated efforts to improve knowledge about the pathological and bacteriological properties of Salmonellae. Acknowledgment of the pioneers in the battle against bacterial meningitis is long overdue.