ROANOKE TIMES
Copyright (c) 1997, Roanoke Times
DATE: Sunday, January 19, 1997 TAG: 9701170037
SECTION: EXTRA PAGE: 9 EDITION: METRO
SOURCE: THOMAS V. DIBACCO THE WASHINGTON POST
Poliomyelitis (or polio) is no longer the scourge that it was 100 years ago when the first American epidemic occurred in Rutland County, Vt. Indeed, the World Health Organization recently declared the disease eradicated in the Western Hemisphere, with the likelihood of worldwide elimination by 2000.
The disease appears to be an ancient one; early Egyptian pillars portray its paralysis. But it wasn't until 1840 that a German scientist, Jacob von Heine, described polio as a distinct malady.
In 1894, when the disease ravaged rural Vermont, the greatest number of its 132 victims were children between the ages of 5 and 10, and it became known as infantile paralysis.
Polio, which is spread only by humans, is caused by any one of three picornaviruses that take root in the intestines. They enter the body, often through the alimentary tract (in contaminated saliva, for example), and spread via the bloodstream to nerve fibers and other parts of the central nervous system.
The effects of the virus on nerve cells, which control muscle movements, vary significantly. Most (90 percent) are so slight as to escape detection; others result in short-lived symptoms, such as headache, fatigue, fever, stiffness in the neck and pain in the extremities.
But some invade the brain stem, causing weakness in muscles that affect swallowing, facial expression and breathing, necessitating the use of an ``iron lung'' to sustain respiration. Invasion of the spinal cord causes paralysis of the arms and legs or of the trunk.
Approximately 2 percent to 5 percent of children and up to 30 percent of adults with paralytic polio die. Survivors with paralysis usually find the condition permanent if recovery doesn't occur within six months.
Early forms of the iron lung enclosed the entire body of patients save for the head; subsequent technology limited the apparatus to the chest. Confinement in the iron lung was in many cases temporary, with gradual exposure to outside conditions. The two-phase therapy was designed to restore respiratory muscles so breathing could be accomplished without mechanical assistance.
In the years after the first outbreak in the United States, polio was given little attention. Its incidence was much lower than other diseases that affected children: 2.2 cases per 100,000 population in 1920, as opposed to 480.5 for measles, 95.9 for smallpox, 151.6 for scarlet fever and 33.8 for typhoid. But polio was a mystery to health officials on both sides of the Atlantic, with developed areas such as Scandinavia having high rates.
Scattered epidemics struck the United States in 1910: in Batavia, N.Y.; Mason City, Iowa; and Cincinnati, for instance. In 1916, New York reported 9,000 cases, three times higher than Sweden's worst outbreak in 1911.
Increasing numbers of adults were affected by the 1920s; by 1947, only slightly more than half of all cases involved youngsters. The most notable adult victim was a prominent New York politician and Democratic candidate for the vice presidency. Franklin D. Roosevelt was stricken with the disease in 1921 at age 39.
Roosevelt, at first paralyzed, eventually regained use of his arms and upper body. With therapy at the Warm Springs, Ga., rehabilitation clinic he founded, FDR gained the ability to walk with leg braces and crutches and continue his political career, first as governor of New York and then as president of the United States.
In 1938, he founded the National Foundation for Infantile Paralysis to coordinate the fight against the disease. The foundation used its March of Dimes campaign to raise funds for research.
Nevertheless, the number of polio cases continued to rise, reaching a peak of about 37,000 cases annually by 1952. Knowledge of the disease progressed slowly. Viewed initially as a nasal infection because of headaches, fever and upper respiratory pain mimicking a cold, by the 1930s it was seen as an intestinal malady that was likely to affect affluent countries more than undeveloped ones.
The explanation was that the intestinal virus in poor countries affected children early, hence the likelihood of developing high rates of immunity. In the United States, however, good sanitation and nutrition delayed exposure and immunity and increased rates of susceptibility, especially for adults.
In 1934, the discovery of a polio vaccine was heralded, but its effectiveness after a year was unsatisfactory and the use of experimental vaccines became controversial.
Debate was also ignited by Sister Elizabeth Kenny, an Australian nurse, who introduced new therapies. Rejecting immobilization techniques relying on braces, Sister Kenny urged activities that would force victims to use and exercise their affected areas. Her theories were not supported at first in her homeland, but a trip to the United States in 1940 gained her support from the National Foundation for Infantile Paralysis and the American Medical Association. Her techniques are still in use.
Meanwhile, John Franklin Enders, a researcher at Children's Hospital in Boston, headed a research team that by 1949 had isolated and cultivated the viruses causing polio. Their work led American virologist Jonas Salk to devise the first killed-virus vaccine, successfully tested in 1954, to deal with all three viruses.
On April 12, 1955, 10 years to the day after FDR's death, the vaccine, administered in multiple shots, was released for use in the United States. The rate of polio dropped from 23.9 cases per 100,000 in 1954 to 17.6 in 1955, 9.1 in 1956 and 3.2 a year later. By 1965 the rate was less than 0.05.
Salk's killed-virus vaccine, which ensured that the recipient would not develop polio, was overtaken by the work of another American, Albert B. Sabin. His live-virus vaccine was approved for use in 1961 even though there is a slight risk of the disease occurring in recipients. It became the choice in most instances of childhood immunization but last fall the federal Centers for Disease Control recommended that the children receive Salk's killed version for the first two of the required four doses.
Polio's history is not over, however. Researchers in laboratory experiments have manipulated a polio virus into a ``vaccine cocktail'' that might provide protection against many diseases, perhaps even AIDS. And in recent years a post-polio syndrome has been identified, affecting middle-aged victims once thought to be cured. Mimicking the familiar symptoms of muscular weakness, the syndrome, whose cause is unknown, has often been misdiagnosed and only recently has attracted national attention.
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