When I was very young, I remember how worried my mother became each summer because it was the start of the polio season. I also recall seeing films of stricken children attempting to walk, as well as those trapped in iron lungs. For many, such images are only historical in nature - a reminder of past times. But for those alive before 1955, the reality was one of fear and apprehension. Such was life 50 years ago.
The first great poliomyelitis epidemic in the United States began in 1916. Through the years, the disease killed thousands, and paralyzed many more. During the summer of 1921, the most famous polio victim became symptomatic at age 39 - Franklin Delano Roosevelt. The public’s response to the polio epidemic began when Roosevelt started to travel to Warm Springs, Ga., for treatment in the therapeutic waters. Other polio victims soon followed. In 1926, Roosevelt purchased the property. Soon thereafter, he started the not-for-profit Warm Springs Foundation.
During the Great Depression, the Foundation needed funds, and turned to the public for help. Initially, support came from the annual President’s Birthday Ball. In January 1938, then-President Roosevelt established the National Foundation for Infantile Paralysis (NFIP), which was designed to be a nationwide, nonpartisan effort. Movies at the time often were preceded by a newsreel called “The March of Time.” On his radio show, entertainer Eddie Cantor coined an associated term, “March of Dimes,” and encouraged listeners to send their dimes directly to the White House. In 1997, the NFIP changed its name to the March of Dimes.
In 1948, March of Dimes funds were used by Jonas Salk and others to grow the three known types of polio viruses. This eventually led to the development of an experimental killed-virus vaccine. In 1952, Salk tested the vaccine against children who had already recovered from polio. Levels of circulating antibodies increased markedly. Next, Salk tested the vaccine against persons who had not experienced polio. Included were Salk, his wife, and children. No one became ill. Based on these results, nationwide testing began in 1954.
The March of Dimes holds a unique position in American history. The effort was the first nationwide biomedical initiative spearheaded by a charitable organization. The March of Dimes marked the start of the volunteer movement that has become an integral part of American society. Prior to the development of the vaccine, an estimated 50,000 people a year were affected by polio. The peak year for polio in the United States was 1952 when 52,000 cases were documented. Of these, 21,000 people were paralyzed, and more than 3,000 died. In 1979, the last case of wild-virus polio occurred in the United States. In 1991, polio was eliminated in the western hemisphere.
Jonas Salk’s vaccine involved the injection of formaldehyde-killed polio virus (IPV). It was licensed in 1955. Albert Sabin’s live, attenuated vaccine was given orally (OPV), and became available in 1961. Soon the OPV became the prime form of polio prevention. In 1999, doctors in the U.S. reverted to the sole use of an enhanced potency IPV following concerns about vaccine-associated paralytic polio, and the possible shedding of live virus.
IPV includes three primary doses (at stages of two, four, and six to 18 months with an interval of at least four weeks). The third dose is somewhat of a booster. A fourth dose is given before or when a child enters school. Routine immunization of adults who reside in the U.S. is not necessary or recommended. Most adults are already immune naturally, and have a small risk of exposure to wild polio virus while in this country.
Since 1988, when the World Health Assembly resolved to eradicate polio, tremendous progress has been made in the global fight against the disease. The number of polio cases worldwide has decreased from 350,000 in 1988 to less than 700 cases in 2003. Seventy-five percent of all cases globally can be linked to a handful of polio “hot spots” in countries such as Nigeria, Pakistan, India, and Indonesia.
OSAP, the Organization for Safety & Asepsis Procedures, is dentistry’s prime source for evidence-based information on infection control and prevention, and human safety and health. More information concerning vaccines and polio is available on the OSAP Web site at www.osap.org.
Dr. Charles John Palenik is an assistant director of Infection Control Research and Services at the Indiana University School of Dentistry. Dr. Palenik is the co-author of the popular “Infection Control and Management of Hazardous Materials for the Dental Team.” He serves on the Executive Board of OSAP. Questions about this article or any infection-control issue may be directed to firstname.lastname@example.org.