Raymond E. Ryckman, a Seventh-day Adventist scientist with top-secret U.S. government clearance and a leading expert on Chagas disease, has died just a month after his 99th birthday.
Ryckman — who got involved in medicine through the influence of Native Americans visiting his family’s farm in the 1920s — conducted grant-funded research for the United States Army at the School of Tropical and Preventive Medicine, the forerunner of Loma Linda University’s School of Public Health.
His 1950s research determined how to protect military troops from plague in plague-infested parts of the world, including a U.S. Army flea control program in Vietnam. His studies with the School of Tropical and Preventive Medicine are credited with playing a significant role in the prevention of plague outbreak during the Vietnam War.
“By establishing a national and global reputation, Dr. Ryckman helped begin a long history of research endeavors at Loma Linda,” said Richard Hart, president of Loma Linda University Health. “This fit well with our international involvement in mission hospitals throughout the world.”
But Ryckman is best known for his contributions in the field of Chagas disease, a parasite-caused infection that can result in serious inflammation of the skin and spread to heart and intestinal-tract tissues. The World Health Organization has recognized Ryckman as the foremost North American entomologist in the field of Chagas disease from the vector Triatoma, or bloodsuckers, also known as “kissing bugs.”
Ryckman found that insecticide prevention is the only suitable therapeutic agent for the control of Chagas disease, which affects an estimated 15 million people in Central and South America and 100,000 in the United States annually.
Ryckman was born on June 19, 1917, and reared on a farm in rural Wisconsin. His father, with only three years of education, thought that eight years in elementary school would be enough for his son.
But an early fascination with medicine led him to pursue his studies.
As a boy, Raymond had great curiosity and respect for Native Americans who made their way through the farm’s forest. The visitors taught him which plants were edible and which were medicinal. He also was fascinated at an early age by insects. In those days, Raymond was a sickly child with many stomach problems.
When a Seventh-day Adventist literature evangelist needed a place to spend the night, Raymond’s mother put him up in the barn with a hired man. During breakfast the next morning, the family noticed that the guest didn’t drink coffee or eat the bacon. Raymond read one of the man’s health books while perched in an apple tree and decided to see for himself if removing pork and coffee from his diet made any difference. His stomach problems disappeared.
Ryckman later went to a camp meeting to learn more about Adventists and joined a church in Dubuque, Iowa, where he learned about Oak Park Academy. He enrolled in the Iowa-based Adventist high school with just a few cents in his pocket and a bar of soap. He paid for his tuition by working in the academy’s broom factory. At the same time, he became a concert violist, sometimes riding a horse to his lessons. He never graduated from high school.
He was drafted into the U.S. Army when he was 24 and served four years at Letterman General Hospital at the Presidio Army Base in San Francisco, California. During this time, he attended a dynamic Adventist church in San Francisco. When he saw Evelyn Larson there, he told an old friend, Bruce Halstead, “Before this day is over, I’m going to know that young lady.”
Evelyn Larson, a nurse, took a great risk in marrying a man who was not even a high school graduate, according to their daughter, Ruby. She thought he would become a minister.
After earning an associate of arts degree from San Francisco City College, Ryckman started his career in 1948 at the University of California, Berkley, as a student of Robert L. Usinger, who is regarded as the greatest U.S. hemipterist in the field of medical entomology.
Ryckman earned a bachelor’s degree in zoology from the University of California, Berkeley, in 1950. He completed his master’s thesis on the Cimicidae (bed bugs) in 1957 and continued under Usinger’s mentoring for his doctoral degree from the University of California, Berkeley, in 1960, which focused on Triatomine vectors of Chagas disease in western North America. Ryckman’s doctoral thesis, titled, “Biosystematics and hosts of the Triatoma protracta complex in North America,” is still looked upon as one of the most thorough and critical studies on the ecology and development of a group of ectoparasitic arthropods and their hosts.
Ryckman helped start the School of Tropical and Preventive Medicine in 1950. He was always extremely proud of that time. When the building was razed in February 1969, he salvaged the sign that hung over the door and placed it as a hello over the main entrance to the Ryckman home in Loma Linda, California.
Ryckman authored or co-authored 120 publications, an impressive output for a time before computers and Internet submissions. Ryckman credits his wife, Evelyn, with carefully and patiently reviewing and editing his manuscripts before submission. His papers are a rich library of information about every aspect of Triatomine and mammalian hosts of T. cruzi.
Ryckman continued his work in retirement, providing consultation, advice, and even an occasional guided field trip for scientists and public health workers from the Americas.
In addition to the invaluable entomological collections that he established, Ryckman’s collection of Chagas’ disease references is perhaps the greatest single reference database ever established for an arthropod-born disease, certainly in the pre-computer age. In a series of volumes published in the Bulletin of the Society of Vector Ecologists from 1981 to 1987 (vols. 6, 9, and 12), Ryckman, with the assistance of several students, compiled more than 23,000 references in Spanish, French, Portuguese, and English, on Chagas disease, covering its biology, pathology, ecology, and entomology. It is considered to be a treasure for generations of researchers to come. This database has now been digitized and is in the process of being prepared for online access.
In 1972, Ryckman was honored with a patronym: Triatoma ryckmani, a rare species that has been found only a few times in Central America. In 2007, he received the Distinguished Achievement Award from the Society for Vector Ecology by the U.S. government’s Centers for Disease Control and Prevention in Atlanta, Georgia.
Ryckman chaired the Loma Linda University School of Medicine Department of Microbiology from 1980 to 1987. He taught himself how to do sleight-of-hand to demonstrate to his students that things are not always what they may appear to be in research, and scientists should repeat work until they are sure of the outcome.
In 1998, Ryckman co-authored the book Son of the Living Desert, detailing the life of his friend Edmund C. Jaeger, a biologist well-known for his studies of the ecology of the desert of the southwestern United States. Jaeger attended Adventist Church cofounder Ellen G. White’s dedication of the Loma Linda Sanitarium in spring 1906, and he was active in the church’s functions from 1904 to 1920, as revealed by his bibliography of more than 160 articles in church publications. In one year, he gave 500 lectures to more than 50,000 people on temperance, practical hygiene, moral virtue, and ethics.
In 2008, Dr. Ryckman received the highest honor awarded by Loma Linda University, the University Distinguished Service Award. The Raymond E. Ryckman Chair in Microbiology supports research at Loma Linda University.
“Few have spanned the history of this place, with such devotion to our mission, as Dr. Ryckman,” Hart said. “He is one of those pillars on our campus who will be missed.”
Ryckman was ahead of his time. The College of Medical Evangelists, as Loma Linda University was once known, focused on teaching and producing Adventist health care professionals. Ryckman not only got federal grants for his work, but also paved the way for others to get grant funding. He helped change the climate of Adventist education, proving that education and research could coexist and helping put Loma Linda University on the world map.
Ryckman, who died on July 18, 2016, is survived by his wife, Evelyn; their three children, Ruby, Albert, and Joseph; and many grandchildren and great-grandchildren.
Richard A. Schaefer is the historian at Loma Linda University Health.