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GEORGE AND DICK, GLADYS 1881-1967, 1881-1963

SCIENTISTS

Achievements

George and Gladys Dick, a husbandand-wife team of scientists, were able to control scarlet fever, a disease that had taken its toll on thousands. The Dicks did not find a cure for scarlet fever, but they were responsible for creating a test to determine an individual's susceptibility and for creating a way to prevent the disease.

Early Lives

Dr. George Francis Dick was born in Fort Wayne, Indiana, attended Indiana University, and was a graduate of the Rush Medical School in Chicago. Dick found his calling in the area of researching contagious diseases. It was during his studies in this area that George Dick met Gladys Henry. Henry earned a bachelor of science degree at the University of Nebraska and went on to receive the M.D. at Johns Hopkins in 1907. She did postgraduate work at Hopkins and at the University of Berlin. In 1911 Henry moved to Chicago, where her career and personal paths intersected with those of George Dick when both served as research pathologists at the University of Chicago. They were married in 1914.

Searching for the Germ

George Dick soon went to work at the McCormick Institute for Contagious Diseases, while Henry was in charge of the laboratory of the Childs Memorial Hospital. Both of the doctors devoted their research to the identification of the germ that causes scarlet fever, for as they stated in the American Journal of Public Healthy "the intelligent prevention treatment of a disease must depend on a definite knowledge of its cause. Attempts to learn the etiology of scarlet fever have long been hampered by failure to obtain the disease experimentally."

Early Investigation

The initial research was conducted using animals such as guinea pigs, mice, rabbits, dogs, pigeons, and small white pigs as subjects. Although some of the animals became sick, none exhibited all of the symptoms of scarlet fever. The Dicks were forced to conclude that human subjects were necessary if their research was to continue. Luckily, several of the Dicks' friends believed in their research and volunteered to be infected with the disease in the name of science. The Dicks also never hesitated to try upon themselves the treatments meant for the volunteers.

First Human Experiments

The first series of volunteers in 1921 were inoculated with fresh whole blood, blood serum, or throat mucus from acute cases of scarlet fever, but results were negative. The next group was inoculated with the organism most usually associated with the disease, hemolytic streptococcus, but the disease did not fully manifest itself.

Success

Producing experimental scarlet fever was not an easy task since the causative agent was unknown and less than half of those exposed to scarlet fever ever contracted the disease. After many tests with no success, the Dicks decided that their failure was perhaps due to an insusceptibility on the part of the volunteers. The Dicks started new experimentation with a group of volunteers who could give a complete family history and who had never been exposed to the disease. This group of volunteers was inoculated with a pure culture of hemolytic streptococcus which had been isolated from a lesion on the finger of an infected nurse. In 1923 the Dicks had their first case of experimentally produced scarlet fever, After additional research, the Dicks concluded that hemolytic streptococcus was the germ that caused scarlet fever.

Preventive Measures Introduced

With their medical knowledge of the immune system, the Dicks knew that the germ would produce a toxin in the body which would stimulate the creation of an antitoxin to fight the disease. Using a laboratory-created toxin from the scarlet fever germ, the Dicks found that injecting subjects with a diluted form of the toxin would produce a skin reaction if the subject was susceptible to the disease. Subjects who had had the disease showed no reaction. Therefore, this new skin test conclusively showed susceptibility or immunity and identified those in need of inoculation.

Immunization Developed

The immunization developed after the Dicks discovered that larger amounts of this toxin injected into subjects with a positive skin test made the skin test negative. Experience showed that three doses of toxin given at five-day intervals gave the best protection. However, the immunization had to be carried to the point of a negative skin test.

Use of the Process

Practical use of the Dick skin test and immunization began immediately. The New York City Board of Health sent for the toxin as soon as the experimentation was complete. Health officials seemed to agree with what the Dicks wrote in the American Journal of Public Health in 1924: "Because complications may occur so early in scarlet fever, and the damage done by the disease is to be estimated not so much in the number of deaths as in the after effects, the importance of preventive immunization is apparent."