A good friend of mine had polio as a child and I remember playing cards with her while she was bedridden. Now she is coping with post-polio syndrome. I have sent her information to try to understand what’s going on and links to support groups.
Post-polio syndrome (PPS) is a condition that affects a lot of people who had polio many years earlier. Polio (short for poliomyelitis, once called infantile paralysis) is a disease caused by a virus that can infect the nervous system, sometimes resulting in paralysis. Until the 1950s, polio disabled or killed thousands of people, mostly children and young adults, each year in the United States and countless others worldwide. Thanks to the Salk vaccine, and soon afterward the Sabin oral vaccine, natural polio infections have been eliminated from the United States for nearly thirty years. Both vaccines were developed fifty years ago with funding from the March of Dimes. However, many survivors of past polio epidemics are developing new problems.
The main symptom of PPS is new muscle weakness that gradually worsens. It often is paired with decreased muscle strength during activities, muscle and joint pain, muscle wasting and severe fatigue. Even muscles that were believed to be unharmed by the first bout with polio may be affected. Less often, breathing difficulties and swallowing problems may occur. These symptoms usually develop 15 years or more after the original illness.
The causes of PPS are not completely understood. Many researchers believe that PPS symptoms result, at least in part, from the unusual stress placed on surviving nerve cells. During the first attack of polio, some of the nerve cells (called motor neurons) in the spinal cord that control muscles are damaged or destroyed. Without impulses from these nerve cells, a muscle cannot function. Fortunately, some motor neurons usually survive the polio attack and send out new nerve connections to the orphaned muscle cells in an attempt to take over the work of the nerve cells that were destroyed. This process makes it possible for an individual to regain at least some use of affected muscles. But, after many years, the overburdened nerve cells may begin to fail, resulting in new muscle weakness.
The normal aging process also may play a role. With age, most people have a decrease in the number of motor neurons in their spinal cords. Persons who have not had polio can lose a considerable number of motor neurons as they age without experiencing any serious muscle weakness. However, among polio survivors who already have lost many motor neurons, this age-related loss may contribute to new muscle weakness.
The March of Dimes provides information to PPS patients and concerned professionals, and has provided grant support for research projects seeking improved treatments for PPS. In May 2000, the March of Dimes, in collaboration with the Roosevelt Warm Springs Institute for Rehabilitation, held an international conference on PPS, during which leading experts in the field shared information on its causes, diagnosis and treatment. A report of the conference’s proceedings has been published and distributed to medical professionals in order to help improve the care of PPS patients.
If you would like more information on post-polio syndrome, send a request to Askus@marchofdimes.org.