|
The Disease Polio was one of the most dreaded childhood diseases of the 20th Century in the United States. An epidemic in 1916 killed 6,000 people and left 27,000 more paralyzed. In the 1950's, parents refused to let their children go to movies or go swimming for fear of catching the disease. Most
of us don't remember how terrified parents were that polio would leave
their children unable to walk or force them to spend the rest of their
life in an iron lung. Since polio vaccine became available in 1955 the
disease has disappeared from the U.S., and may soon be gone from the rest
of the world as well. The number of cases of paralytic polio in the United
States has fallen from more than 20,000 in 1952 to only a few cases a
year ago today. The few cases that have occurred in recent years have
not been caused by the natural disease, but by one type of polio vaccine
as we will explain below. But
even though there is no polio in the United States, or in fact in the
Western hemisphere, it is still common in some parts of the world. A single
infection brought into the country by someone traveling from one of these
regions could lead to polio epidemics all over again if we were not protected.
That is why we continue to vaccinate. Polio
is caused by a virus that lives in the throat and intestinal tract. It
is spread through contact with the bowel movements of an infected person
(for instance, by changing diapers). Some
children who get polio don't feel ill at all. For others, polio simply
feels like a cold, with symptoms appearing about 6-20 days after exposure.
Sometimes these children will also feel some pain and stiffness in their
neck, back, and legs, but this soon goes away. However, some children who get polio become paralyzed . that is, they lose the use of their muscles. This is called paralytic polio. Paralytic polio can start like a common cold, but often with severe muscle pain. Paralysis usually comes within the first week. Most often it affects the child's legs, but sometimes it affects other muscles including those that control breathing. Some children recover from their paralysis, but many will be permanently disabled. There is no treatment for polio, and some children die from it. Polio
is most contagious from about 7-10 days before symptoms appear till about
7- U.S.
DEPARTMENT OF HEALTH & HUMAN SERVICES |