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A Brief History of Polio
From Ancient Egypt to the 20th Century
Polio has probably caused paralysis and death for most of human history. The
oldest clearly identifiable reference to paralytic poliomyelitis is an Egyptian
stele (stone engraving) over 3,000 years old. Cases of poliomyelitis tended to
be rare in ancient times, though, as sanitation was generally poor. With
improvements in waste disposal and the widespread use of indoor plumbing in the
20th century, epidemics of polio began to occur with regularity in the developed
world, primarily in cities during the summer. Because sewage was dumped away
from the drinking water supply (a development which helps combat a number of
other diseases, including cholera), babies were much less likely to be infected
with polio and gain protective immunity. As the children got older and began
playing with others, swimming in public pools, and going to school, they were
more likely to be exposed to the virus, which was then more likely to cause
paralytic poliomyelitis.
H.L. Mencken writes of polio epidemics occurring virtually every summer in
Baltimore during his childhood in the late 1890s, and this tragic cycle
continued through the 1950s. Though the virus only paralyzes about 1% of the
individuals it infects (most infections are
asymptomatic or result only in a self-limiting diarrhea), it tends to be
transmitted very easily under the right conditions. One percent of all children
in a large city translates into thousands of cases, and the emotional and
economic impact of such epidemics was staggering. The brochure below was
distributed a few years before the vaccines were available.
 Vaccination
and Eradication
By the time of the Great Depression, paralytic poliomyelitis was perhaps the
most feared disease known. Polio struck fast, there was no cure, and it crippled
its victims for life. Hobbling on crutches, rolling in wheelchairs, or lying
immobile in giant iron lungs, the legions of sufferers accumulated from year to
year. Even the exact mechanism of polio's
transmission was a hotly debated subject for many years, so many areas were
placed under strict quarantine when cases of the disease began to manifest
themselves. Only the fear surrounding AIDS can rival the feelings people had
about polio in the first half of this century.
President Franklin Roosevelt declared a War on Polio during his
administration, and the tremendous resources of postwar America were brought to
bear on the problem of developing a vaccine. From the beginning of this effort,
it was clear that such a vaccine was at least theoretically feasible, as
contrasted with such pathogens as malaria and HIV, where no such assurance
exists. In the early 1960s, the work bore fruit, first with the Salk vaccine,
and soon after with the Sabin virus strains.
Salk used chemical and heat treatment to kill poliovirus, then injected this
inactivated virus into patients. The proteins of the destroyed virus "taught"
the patients' immune systems to recognize polio, and they were then protected
from subsequent infection. Sabin's approach was to grow the virus in the
laboratory under a variety of conditions, allowing it to accumulate mutations.
Ultimately, this resulted in an attenuated virus which could be given to a
patient orally. The weaker virus
replicates normally in the intestine, but cannot grow well enough to
invade the central nervous system. Once again, the immune system "learns" to
recognize polio, and this confers protection.
Once the Sabin and Salk vaccines were proven effective, the disease was
rapidly eradicated throughout most of the industrialized world. The economic
effect has been enormous; it has been calculated that the polio vaccine pays for
the costs of its development approximately every three weeks. The benefit to the
United States alone for this single breakthrough runs into the trillions of
dollars. The social impact has been incalculable. The crutches, wheelchairs, and
iron lungs of polio victims have at last been banished from children's and
parents' nightmares, at least in the developed world.
Recently, the World Health Organization
embarked on a campaign for the
worldwide eradication of polio. If this plan is completed successfully, it
will conclude the second deliberate destruction of a virus by humans, and stand
as the final victory in Roosevelt's other war.
Print and Video Resources
- Polio and the
era of fear For a time, polio was the most feared disease in the
developed world. This book tells the story of that time.
- Halstead, Lauro, "Post Polio Syndrome,"
Scientific American, April 1998, pp.
42-47. An excellent review of the current state of knowledge about this
perplexing condition. The full text of this article is available on the
Lincolnshire PPS site.
- The Story of Polio The
Web site of a PBS special about the history of the disease.
- The Last Child The site
for a new documentary film entitled "The Last Child," about the global polio
eradication effort.
Post-Polio Syndrome (PPS)
- Support Groups and Centers
- International Polio Network A
group which provides information about post-polio syndrome as well as
ventilators. Based in St. Louis, Missouri.
- Lincolnshire
Polio Site Maintained by Chris Salter in the UK, this is an
outstanding site for up-to-date information about PPS and polio. Includes
the full text of the Halstead article referenced above.
- Post-Polio
Institute at Englewood Hospital A PPS treatment center based in
Englewood, New Jersey, with an informative, straightforward Web site that
should be useful for anyone interested in learning more about this
condition.
- Portuguese
Post-Polio Association A post-polio support group based in Portugal, for
those readers located on that side of the Atlantic. Since nobody here at
PICO reads Portuguese, we cannot provide any further comment on the site's
content. It does produce a pop-up window with an advertisement in English
when you get there, though.
- Medical Information and News
Always take medical information on the Internet with a large grain of salt,
and if you think you need treatment, see a doctor in person. With that
in mind, here are a few information sites that might be of interest.
- PPS Information An
information and link page about PPS - lots of resources for PPS sufferers
and polio survivors. Animation and sound make this a bad site for those with
slow modem connections.
Links to the Polio Eradication Front
- The Albert B. Sabin Vaccine Institute A
nonprofit organization dedicated to advancing the vision of Albert Sabin.
This group helps support the development of new vaccines and the distribution
of existing ones for a variety of diseases.
- Ending polio - now
or never? Timing may be crucial for the destruction of this virus, and
this article argues that the current opportunity may not come around again.
- Rotary Club of
Wanganui Daybreak The Rotarians have been instrumental in the
eradication campaign, and this New Zealand chapter is actively raising funds
to continue the effort.
- The Vaccine Site An information
resource assembled by the editors of Unisci.
The site is conveniently broken into links of interest to parents, medical
practitioners, and researchers.
- WHO Polio Eradication Effort From
the people largely responsible for the effort, a site about it. We might not
always
agree with their approach, but we applaud the goal.
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