Infection, Immunity and Serum Therapy: In Relation to the Infectious Diseases Which Attack Man; with Considerations of the Allied Subjects of Agglutination, Precipitation, Hemolysis, Etc
Howard Taylor Ricketts was an American microbiologist, pathologist, and bacteriologist. He is remembered for discovering the causative organism of Rocky Mountains spotted fever and abardillo, both forms of typhus fever, and how they are transmitted.
Background
Howard Taylor Ricketts was born on February 9, 1871 in Findlay, Ohio, the second child and second son in a family of seven. His father, Andrew Duncan Ricketts, was descended through a line of English ancestors from William Ricketts, who settled in the Jerseys of North America in the latter part of the seventeenth century. His mother, Nancy Jane Taylor, was descended from Thomas Taylor, who was born about 1767 and emigrated to America in his youth. The Ricketts family lived in Ohio and Illinois until 1892, when they moved to Lincoln, Nebraska.
Education
In 1890, after completing preparatory school, Ricketts entered Northwestern University. Two years later he transferred to the University of Nebraska. Howard received a Bachelor of Arts degree from the University of Nebraska in 1894, having transferred from Northwestern University. He was graduated from the Northwestern University Medical School in 1897.
In 1898 Ricketts received a pathology fellowship at Rush Medical College. Ricketts served his internship in the Cook County Hospital in Chicago. His unusual ability when an intern was recognized and he was appointed a fellow in cutaneous pathology in Rush Medical College and served two years. In this period he accomplished his research on blastomycetic dermatitis which was of such outstanding character that it became evident that there was a researcher of unusual promise.
Shortly after finishing his term as a fellow in cutaneous pathology, he went abroad for a year of study in foreign laboratories, chiefly in Vienna and in the Pasteur Institute in Paris. Here he worked in immunology, and before his return, he received an appointment in the department of pathology of the University of Chicago.
In 1902 Ricketts became an associate professor of pathology at the University of Chicago. That same year, the state of Montana began funding medical research into the aetiology of Rocky Mountain spotted fever. While this disease rarely claimed more than a dozen lives in a year, it was particularly virulent in Bitterroot Valley, an increasingly prosperous and influential community.
In 1906, with funding from the McCormick Memorial Institute, the State of Montana, the University, and the American Medical Association, Ricketts travelled to Montana to study the disease, which had a mortality of 80-90 percent. For the next four years, Ricketts divided his life between campus-based laboratories and his research in the field. As part of his research, he contacted victims of the disease, collected and studied affected animals, and raised additional funds for his project.
Not until the second year of his investigation, however, did Ricketts and his assistant J. J. Moore make a critical breakthrough by discovering that wood ticks were the primary carriers of the bacillus that caused the fever.
By 1909, using laboratory animals, Ricketts was able to demonstrate that ticks transmitted the disease and this finding led to a public health campaign to destroy the reservoir of the disease. He based his ideas on the successful model of Texas tick fever that had been worked out by Theobald Smith (1859-1934) and others. Rickett’s work suggested that bacterial diseases could be biologically transmitted from pests to people.
In 1910 Montana suffered an outbreak of typhoid fever and smallpox, and money ordinarily spent on preventing spotted fever was diverted to fight these diseases. Ricketts thus accepted an invitation to examine typhus in the Valley of Mexico. Similarities between typhus and spotted fever would perhaps provide him with the key to the aetiology of the diseases. He discovered that lice transmitted the fever, and he worked closely and rapidly with severely infected patients.
In 1909 Ricketts and his assistant, Russell M. Wilder, went to Mexico City to study tabardillo - a Mexian form of typhus. There he discovered that typhus closely resembled spotted fever, leading him to argue that insects spread both diseases. Unknown to Ricketts, this same conclusion had been reached by the French surgeon Jules Henri Nicolle (1866-1936, winner of the 1928 Nobel Prize in Physiology or Medicine), who identified lice as the culprits. Ricketts's final stint of research was cut short by a critical illness. Just days after isolating the microorganism he contended was the cause of typhus, Ricketts died on May 5, 1910, most likely from an infected insect's bite.
His work was eminently successful. In a short time, he demonstrated that the disease could be transmitted to the monkey and that the agent of transmission is chiefly the louse, and again he found micro-organisms of the class of the Rickettsia, which later were established as the cause of the disease. This information was of enormous value in combating the epidemics of typhus in the First World War, and in controlling the disease were found in less than epidemic proportions. Unfortunately, while pushing these studies in Mexico City, Ricketts was stricken with typhus and died in the midst of his successful work, becoming one of the lists of medical martyrs to the disease he was studying. In so brief a time he had accomplished so much that the cutting-off of his life at the age of thirty-nine was a calamity of the first class.
Achievements
Ricketts is renowned for discovering the causative organism and the transmission route of Rocky Mountain spotted fever and of tabardillo – an epidemic louse-borne typhus occurring especially in Mexico. He also found that both diseases were caused by related infectious agents (Rickettsia rickettsii and Rickettsia prowazekii). The scientific community, therefore, named both a taxonomic family (Rickettsiaceae) and an order (Rickettsiales) after the scientist.
He provided the basis for a rich understanding of Rickettsia by working intensively with Rocky Mountain spotted fever and Mexican typhus fever. The genus now includes all the very small, gram-negative, bacterium-like organisms found in arthropods and capable of transmission to some vertebrates. Difficult to stain, with Machiavello’s technique, Rickettsia appears red against a bluish background. Henrique da Rocha-Lima named them in honor of Ricketts in 1916.
Ricketts also pioneered the use of laboratory animals for inoculation experiments and disease identification. His work on immunity and serums became the basis for further advances in vaccine development.
Many of the observations and discoveries in connection with his work have a much wider significance, and will surely prove of value and service on the ever-shifting battleground with infectious diseases.
In his youth, Ricketts was motivated by deep Methodist conviction.
Views
Finding that ordinary cultures did not reveal the cause of the disease Ricketts went at once to animal inoculation and found that the disease is communicable to lower animals and that a certain tick can transmit the disease from sick to healthy animals and to man. He found that the tick is itself a victim of infection, for the virus proliferates in the tick and may be transmitted through the eggs, in which it is found abundantly, as well as in the larval and nymphal stages of development. These observations opened a new field and he devoted himself untiringly to the many problems that arose in the laboratory and in the field.
Some of the experiments devised to lay bare the secrets of the different orders of living things concerned in spotted fever are masterful in their ingenuity and comprehensiveness, notably those bearing on the hereditary transmission of spotted-fever virus in ticks, on the occurrence of infected ticks in nature, and on the part played by small wild animals as a source for the virus.
He discovered in the blood of patients, in the ticks and their eggs, a small organism which he rightly assumed to be the cause of the disease, and now this and related organisms responsible for many important diseases are known as Rickettsia, in memory of the man who first identified them.
One of the amazing things about Ricketts was the uncanny accuracy with which he conducted his investigations. There was no fumbling; no steps had to be retraced; no premature conclusions had to be retracted. Struck by the resemblance of Rocky Mountain fever to typhus fever, he undertook an investigation of that disease in Mexico City.
Quotations:
"One can only say that the truth will be pursued, whatever the ultimate result may be."
Personality
During his third year of medical school, Ricketts suffered a nervous breakdown.
Quotes from others about the person
Wolbach of the Harvard Medical School wrote an apt eulogy: “Ricketts brought facts to light with brilliance and accuracy and indicated by the methods he used, most of the major lines of development subsequently employed in the study of rickettsial diseases.”
Connections
On April 18, 1900, Howard Taylor Ricketts was married to Myra Tubbs, of Kirkwood, Illinois. While in Berlin his son, Henry was born and later a daughter, Elizabeth was born as well.
Father:
Andrew Duncan Ricketts
Mother:
Nancy Jane Taylor
Spouse:
Myra Tubbs
Daughter:
Elizabeth Ricketts
Son:
Henry Ricketts
colleague:
Russell Wilder
After Ricketts arrived in December 1910 to Mexico City, he and Russell Wilder, his graduate student assistant from the University of Chicago, spent four months conducting tests on a small population of laboratory monkeys.
Rickets and Wilder, achieved a lot in the short period prior to the death of Ricketts. They found that tabardillo can be transmitted by the body louse (Pediculus humanus) and that it was caused by an organism similar to the one causing Rocky Mountains spotted fever. Ricketts also demonstrated that tabardillo can be transmitted to monkeys, which, after recovering, would develop immunity to the disease.
