FLEXNER, SIMON 1863-1946

PATHOLOGIST

Accomplishments

The accomplishments of Simon Flexner, pathologist and director of the Rockefeller Institute for Medical Research, were extraordinary in their diversity and impact. Flexner was the fourth of nine children born to Morris and Esther Flexner in Louisville, Kentucky. Abraham Flexner, the education specialist, was his brother. As a young man Simon Flexner was apprenticed to a druggist who sent him to the Louisville College of Pharmacy. After graduating in 1882, Flexner's interest in medicine led him to study at the University of Louisville where he earned an M.D. in 1889. This early education and Flexner's investigative nature set the stage for his remarkable career.

Early Work

After medical school Flexner turned his talents to research in the fields of pathology and bacteriology. He began his work at the Johns Hopkins Hospital where he became an associate in pathology in 1892. Flexner conducted his research under the tutelage of William H. Welch, whom he considered a major influence in his life. Flexner also studied in Europe at Strasbourg and at Prague.

Meningitis

An outbreak of cerebrospinal meningitis in Maryland in 1893 gave Flexner experience in the area of infectious diseases. This experience proved valuable while Flexner was in Manila studying the diseases of the Philippine Islands. There he was able to isolate a widespread strain of dysentery, since known as the Flexner type.

Academic Career

By 1898 Flexner was promoted to full professor of pathological anatomy at Johns Hopkins. He moved to the University of Pennsylvania as a professor of pathology from 1899 to 1903. While in Pennsylvania Flexner researched problems in the areas of pathology, bacteriology, and immunology, and managed a governmental commission investigating bubonic plague in San Francisco. He also influenced the career of a brilliant Japanese physician, Hideyo Noguchi.

The Rockefeller Institute

Flexner is widely known for his work as the director of the Rockefeller Institute for Medical Research, which was created in 1901. Excited by the possibilities presented by this new corps of investigators devoting all their time to medical research, Flexner accepted a position as one of the seven members of the institute's board of scientific directors. The board was headed by Flexner's mentor, William Welch. With Welch's advice Flexner organized the institute into several laboratory departments, instead of limiting its work to one particular subdivision of medical research. In 1924 Flexner was formally recognized for his outstanding contributions and named as director of the institution.

Research Breakthroughs

The Rockefeller Institute was gradually becoming internationally famous, partly due to the scientific achievements of Simon Flexner. Throughout his tenure at the institute Flexner still continued his research. In 1905, when New York was faced with an epidemic of cerebrospinal meningitis, Flexner conceived the idea of injecting serum into the spinal canal. This method reduced the death rate from the disease by half. In 1907, during a poliomyelitis epidemic, Flexner found that the infectious agent was a filterable virus rather than a bacterial organism. His work in this area laid the groundwork for the development of the polio vaccine.

Honors and Achievements

Flexner was the editor of the Journal of Experimental Medicine for nineteen years and published reports on his research in pathology and bacteriology. He was chairman of the Public Health Council of New York State and a trustee of the Johns Hopkins University and of the Carnegie Foundation of New York. His most notable achievement mayu be that of melding a group of individualistic senior colleagues into the renowned Rockefeller Institute.