Sabin, Albert (1906-1993)

views updated May 23 2018

Sabin, Albert (1906-1993)

Russian American virologist

Albert Sabin developed an oral vaccine for polio that led to the once-dreaded disease's virtual extinction in the Western Hemisphere. Sabin's long and distinguished research career included many major contributions to virology , including work that led to the development of attenuated live-virus vaccines. During World War II, he developed effective vaccines against dengue fever and Japanese B encephalitis. The development of a live polio vaccine, however, was Sabin's crowning achievement.

Although Sabin's polio vaccine was not the first, it eventually proved to be the most effective and became the predominant mode of protection against polio throughout the Western world. In South America, "Sabin Sundays" were held twice a year to eradicate the disease. The race to produce the first effective vaccine against polio was marked by intense and often acrimonious competition between scientists and their supporters; in addition to the primary goal of saving children, fame and fortune were at stake. Sabin, however, allowed his vaccine to be used free of charge by any reputable organizations as long as they met his strict standards in developing the appropriate strains.

Albert Bruce Sabin was born in Bialystok, Russia (now Poland), on August 26, 1906. His parents, Jacob and Tillie Sabin, immigrated to the United States in 1921 to escape the extreme poverty suffered under the czarist regime. They settled in Paterson, New Jersey, and Sabin's father became involved in the silk and textile business. After Albert Sabin graduated from Paterson High School in 1923, one of his uncles offered to finance his college education if Sabin would agree to study dentistry. Later, during his dental education, Sabin read the Microbe Hunters by Paul deKruif and was drawn to the science of virology, as well as to the romantic and heroic vision of conquering epidemic diseases.

After two years in the New York University (NYU) dental school, Sabin switched to medicine and promptly lost his uncle's financial support. He paid for school by working at odd jobs, primarily as a lab technician and through scholarships. He received his B.S. degree in 1928 and enrolled in NYU's College of Medicine. In medical school, Sabin showed early promise as a researcher by developing a rapid and accurate system for typing (identifying) Pneumococci, or the pneumonia viruses . After receiving his M.D. degree in 1931, he went on to complete his residency at Bellevue Hospital in New York City, where he gained training in pathology, surgery, and internal medicine. In 1932, during his internship, Sabin isolated the B virus from a colleague who had died after being bitten by a monkey. Within two years, Sabin showed that the B virus's natural habitat is the monkey and that it is related to the human Herpes Simplex virus. In 1934, Sabin completed his internship and then conducted research at the Lister Institute of Preventive Medicine in London.

In 1935, Sabin returned to the United States and accepted a fellowship at the Rockefeller Institute for Medical Research. There, he resumed in earnest his research of poliomyelitis (or polio), a paralytic disease that had reached epidemic proportions in the United States at the time of Sabin's graduation from medical school. By the early 1950s, polio afflicted 13,500 out of every 100 million Americans. In 1950 alone, more than 33,000 people contracted polio. The majority of them were children.

Ironically, polio was once an endemic disease (or one usually confined to a community, group, or region) propagated by poor sanitation. As a result, most children who lived in households without indoor plumbing were exposed early to the virus; the vast majority of them did not develop symptoms and eventually became immune to later exposures. After the public health movement at the turn of the century began to improve sanitation and more and more families had indoor toilets, children were not exposed at an early age to the virus and thus did not develop a natural immunity . As a result, polio became an epidemic disease and spread quickly through communities to other children without immunity, regardless of race, creed, or social status. Often victims of polio would lose complete control of their muscles and had to be kept on a respirator, or in a low-pressure iron lung, to help them breathe.

In 1936, Sabin and Peter K. Olitsky used a test tube to grow some poliovirus in the central nervous tissue of human embryos. Not a practical approach for developing the huge amounts of virus needed to produce a vaccine, this research nonetheless opened new avenues of investigation for other scientists. However, their discovery did reinforce the mistaken assumption that polio only affected nerve cells.

Although primarily interested in polio, Sabin was "never able to be a one-virus virologist," as he told Donald Robinson in an interview for Robinson's book The Miracle Finders. Sabin also studied how the immune system battled viruses and conducted basic research on how viruses affect the central nervous system. Other interests included investigations of toxoplasmosis , a usually benign viral disease that sometimes caused death or severe brain and eye damage in prenatal infections. These studies resulted in the development of rapid and sensitive serologic diagnostic tests for the virus.

During World War II, Sabin served in the United States Army Medical Corps. He was stationed in the Pacific theater where he began his investigations into insect-borne encephalitis, sandfly fever, and dengue. He successfully developed a vaccine for dengue fever and conducted an intensive vaccination program on Okinawa using a vaccine he had developed at Children's Hospital of Cincinnati that protected more than 65,000 military personnel against Japanese encephalitis. Sabin eventually identified a number of antigenic (or immune response-promoting) types of sandfly fever and dengue viruses that led to the development of several attenuated (avirulent) live-virus vaccines.

After the war, Sabin returned to the University of Cincinnati College of Medicine, where he had previously accepted an appointment in 1937. With his new appointments as professor of research pediatrics and fellow of the Children's Hospital Research Foundation, Sabin plunged back into polio research. Sabin and his colleagues began performing autopsies on everyone who had died from polio within a four-hundred-mile radius of Cincinnati, Ohio. At the same time, Sabin performed autopsies on monkeys. From these observations, he found that the poliovirus was present in humans in both the intestinal tract and the central nervous system. Sabin disproved the widely held assumption that polio entered humans through the nose to the respiratory tract, showing that it first invaded the digestive tract before attacking nerve tissue. Sabin was also among the investigators who identified the three different strains of polio.

Sabin's discovery of polio in the digestive tract indicated that perhaps the polio virus could be grown in a test tube in tissue other than nerve tissue, as opposed to costly and difficult-to-work-with nerve tissue. In 1949, John Franklin Enders, Frederick Chapman Robbins, and Thomas Huckle Sweller grew the first polio virus in human and monkey non-nervous tissue cultures, a feat that would earn them a Nobel Prize. With the newfound ability to produce enough virus to conduct large-scale research efforts, the race to develop an effective vaccine accelerated.

At the same time that Sabin began his work to develop a polio vaccine, a young scientist at the University of Pittsburgh, Jonas Salk , entered the race. Both men were enormously ambitious and committed to their own theory about which type of vaccine would work best against polio. While Salk committed his efforts to a killed polio virus, Sabin openly expressed his doubts about the safety of such a vaccine as well as its effectiveness in providing lasting protection. Sabin was convinced that an attenuated live-virus vaccine would provide the safe, long-term protection needed. Such a vaccine is made of living virus that is diluted, or weakened, so that it spurs the immune system to fight off the disease without actually causing the disease itself.

In 1953, Salk seemed to have won the battle when he announced the development of a dead virus vaccine made from cultured polio virus inactivated, or killed, with formaldehyde. While many clamored for immediate mass field trials, Sabin, Enders, and others cautioned against mass inoculation until further efficacy and safety studies were conducted. Salk, however, had won the entire moral and financial support of the National Foundation for Infantile Paralysis, and in 1954, a massive field trial of the vaccine was held. In 1955, to worldwide fanfare, the vaccine was pronounced effective and safe.

Church and town hall bells rang throughout the country, hailing the new vaccine and Salk. However, on April 26, just fourteen days after the announcement, five children in California contracted polio after taking the Salk vaccine. More cases began to occur, with eleven out of 204 people stricken eventually dying. The United States Public Health Service (PHS) ordered a halt to the vaccinations, and a virulent live virus was found to be in certain batches of the manufactured vaccine. After the installation of better safeguards in manufacturing, the Salk vaccine was again given to the public and greatly reduced the incidence of polio in the United States. But Sabin and Enders had been right about the dangers associated with a dead-virus vaccine; and Sabin continued to work toward a vaccine that he believed would be safe, long lasting, and orally administered without the need for injection like Salk's vaccine.

By orally administering the vaccine, Sabin wanted it to multiply in the intestinal tract. Sabin used Enders's technique to obtain the virus and tested individual virus particles on the central nervous system of monkeys to see whether the virus did any damage. According to various estimates, Sabin's meticulous experiments were performed on anywhere from nine to fifteen thousand monkeys and hundreds of chimpanzees. Eventually, he diluted three mutant strains of polio that seemed to stimulate antibody production in chimpanzees. Sabin immediately tested the three strains on himself and his family, as well as research associates and volunteer prisoners from Chillicothe Penitentiary in Ohio. Results of these tests showed that the viruses produced immunity to polio with no harmful side effects. By this time, however, the public and much of the scientific community were committed to the Salk vaccine. Two scientists working for Lederle Laboratories had also developed a live-virus vaccine. However, the Lederle vaccine was tested in Northern Ireland in 1956 and proved dangerous, as it sometimes reverted to a virulent state.

Although Sabin lacked backing for a large-scale clinical trial in the United States, he remained undaunted. He was able to convince the Health Ministry in the Soviet Union to try his vaccine in massive trials. At the time, the Soviets were mired in a polio epidemic that was claiming eighteen to twenty thousand victims a year. By this time, Sabin was receiving the political backing of the World Health Organization in Geneva, Switzerland, which had previously been using Salk's vaccine to control the outbreak of polio around the world; they now believed that Sabin's approach would one day eradicate the disease.

Sabin began giving his vaccine to Russian children in 1957, inoculating millions over the next several years. Not to be outdone by Salk's public relations expertise, Sabin began to travel extensively, promoting his vaccine through newspaper articles, issued statements, and scientific meetings. In 1960, the U.S. Public Health Service, finally convinced of Sabin's approach, approved his vaccine for manufacture in the United States. Still, the PHS would not order its use and the Salk vaccine remained the vaccine of choice until a pediatrician in Phoenix, Arizona, Richard Johns, organized a Sabin vaccine drive. The vaccine was supplied free of charge, and many physicians provided their services without a fee on a chosen Sunday. The success of this effort spread, and Sabin's vaccine soon became "the vaccine" to ward off polio.

The battle between Sabin and Salk persisted well into the 1970s, with Salk writing an op-ed piece for the New York Times in 1973 denouncing Sabin's vaccine as unsafe and urging people to use his vaccine once more. For the most part, Salk was ignored, and by 1993, health organizations began to report that polio was close to extinction in the Western Hemisphere.

Sabin continued to work vigorously and tirelessly into his seventies, traveling to Brazil in 1980 to help with a new outbreak of polio. He antagonized Brazilian officials, however, by accusing the government bureaucracy of falsifying data concerning the serious threat that polio still presented in that country. He officially retired from the National Institute of Health in 1986. Despite his retirement, Sabin continued to be outspoken, saying in 1992 that he doubted whether a vaccine against the human immunodeficiency virus , or HIV , was feasible. Sabin died from congestive heart failure at the Georgetown University Medical Center on March 3, 1993. In an obituary in the Lancet, Sabin was noted as the "architect" behind the eradication of polio from North and South America. Salk issued a statement praising Sabin's work to vanquish polio.

See also Antibody and antigen; Antibody formation and kinetics; History of immunology; History of public health; Poliomyelitis and polio

World of Microbiology and Immunology

Sabin, Albert

views updated May 14 2018

Albert Sabin

Born: August 26, 1906
Bialystok, Poland
Died: March 3, 1993
Washington, D.C.
Polish-born American physician and virologist

Polish-born physician and virologist (scientist who studies viruses) Albert Sabin developed the first effective and widely used live virus polio myelitis (polio) vaccine.

Early years and education

Born on August 26, 1906, in Bialystock, Poland, Albert Bruce Sabin came to the United States with his parents and three siblings in 1921 in order to avoid persecution (harsh treatment) directed against Jews. They established residence in Paterson, New Jersey. Sabin's father worked in the textile industry in both silk and regular cloth. Sabin worked hard to learn his new language, working odd jobs throughout his high school and college years.

At Paterson High School Sabin participated in after-school activities including the literary and debating clubs. He graduated in 1923. Sabin entered New York University as a predental student, then switched to medical school microbiology (the study of life forms that cannot be seen without the aid of a microscope).

Begins polio research

Upon receiving his medical degree in 1931, Sabin immediately began research on the nature and cause of polio, a viral infection that can result in death or paralysis. This disease had reached epidemic (affecting a huge number of people) proportions, affecting people around the world.

Sabin joined the staff of the Rockefeller Institute in New York City in 1935 and four years later left for a post at the Children's Hospital Research Foundation in Cincinnati, Ohio. It was there that he proved that polio viruses not only grew in nerve tissue, as was generally assumed, but that they lived in the small intestines. This discovery indicated that polio might be vulnerable to a vaccine taken orally (through the mouth).

Sabin's work on a polio vaccine was interrupted by World War II (1939–45; a war fought mostly in Europe with France, Great Britain, the Soviet Union, and the United States on one side, and Germany, Japan, and Italy on the other). In 1941 he joined the U.S. Army Epidemiological Board's Virus Committee and accepted assignments in Europe, Africa, the Middle East, and the Pacific. During this phase of his career Sabin developed vaccines for encephalitis (swelling of the brain), sand-fly fever, and dengue fever (a virus transmitted by mosquitoes).

Develops polio vaccine

At the war's end Sabin returned to Cincinnati and to his research on the polio virus. His approach was to make the human stomach a hostile environment for the polio virus. He intended to accomplish this by isolating a mutant (altered, different) form of the polio virus that was incapable of producing the disease. The avirulent (not able to harm the body's defenses) virus would then be grown and introduced into the intestines. There it would reproduce rapidly, displacing the deadly virulent forms of the polio virus and protecting the human host from the disease.

After an intensive investigation Sabin managed to isolate the viruses he sought. Sabin and his research associates first swallowed the live avirulent viruses themselves before they experimented on other human subjects. For two years (1955–1957) the vaccine was tested on hundreds of prison inmates with no harmful effects.

At this point Sabin was ready for large-scale tests, but he could not carry them out in the United States. A rival polio vaccine developed by Dr. Jonas Salk (1914–1995) in 1954 was then being tested for its ability to prevent the disease among American school children. Salk's approach was to create a vaccine using a killed form of the virus.

Some foreign virologists, especially those from the Soviet Union, were convinced of the superiority of the Sabin vaccine. It was first tested widely in Russia, Latvia, Estonia, Czechoslovakia, Poland, Hungary, and East Germany from 1957 to 1959. A much smaller group of persons living in Sweden, England, Singapore, and the United States received Sabin's vaccine by the end of 1959.

In the meantime Salk's vaccine had been accidentally contaminated with some live virulent polio viruses. It caused death or severe illness to several hundred school children. In addition, the Salk vaccine had to be injected into the body and it was effective for a relatively short time—less than a year. These problems made the American medical community more receptive to Sabin's vaccine.

Sabin's vaccine was free of dangerous viruses, easily administered orally, and effective over a long period of time. Ultimately it was a live virus vaccine that was used in the United States and the rest of the world to eliminate polio.

Later life

Always a tireless researcher, Sabin moved on to a new field of study, the possible role viruses play in creating cancer in humans. After more than a decade of work he was forced in 1977 to conclude that cancers were not caused by viruses as he had first assumed. Sabin served as research professor at the University of South Carolina until 1982. In 1980 he traveled to Brazil to deal with a new outbreak of polio, and retired from medicine in 1986. Sabin died March 3, 1993, of heart failure.

Sabin's work on a vaccine for the polio virus affected millions of people. By 1993 health organizations reported the nearextinction of the polio disease in the Western Hemisphere.