Summit County scientist joins effort to end
polio once and for all
by Dr. David L. (“Woody”) Woodland
(as published in the Summit Daily News of August 8, 2013)
Not that long ago, polio (short for poliomyelitis) was a major scourge in this country, killing many
and leaving many more with temporary or permanent paralysis in cases where the virus
penetrated the central nervous system. In 1952, the incidence of paralytic polio peaked in the
United States with more than 21,000 new cases. However, the subsequent introduction of polio
vaccines resulted in a dramatic decline; the last case of wild-virus polio acquired in the US was
reported in 1979. Clearly, polio vaccines were a huge success, and today we sit on the cusp of
completely eliminating this devastating virus worldwide.
One of the giants in the polio vaccine field died recently. Dr. Hilary Koprowski developed the
world’s first polio vaccines comprised of a live but weakened virus. In a seminal study, Dr.
Koprowski created a modified strain of the virus by repeatedly “passaging” the virus in cotton
rats – a process that involves growing the virus in a rat, collecting it after several days,
inoculating another rat and then repeating the process. The new strain became highly adapted
to its new rodent host and at the same time was severely weakened in its capacity to infect
humans and cause disease. Such weakened viruses can serve as potent vaccines since they
elicit a powerful immune response to the virus without actually causing disease. But this type of
vaccine comes with risks; if the virus is insufficiently weakened, it can revert to a more
dangerous form in some individuals and cause the very disease it is designed to prevent. Dr.
Koprowski was so confident in his procedures that he drank some of the vaccine to confirm its
safety. He suffered no ill effects. Subsequent trials in the United States and abroad confirmed
the vaccine’s efficacy and general safety.
Despite the success of the Koprowski vaccine, there nevertheless remained safety concerns
and it was never adopted by the US medical community. Instead, a killed form of the virus
generated by Dr. Jonas Salk was introduced as an injectable vaccine in the mid-1950s. This
was subsequently followed by a live but weakened virus developed by Albert Sabin in the late
1950s.The Sabin vaccine was delivered orally and was very similar to the vaccine developed by
Dr. Koprowski, but even more severely weakened. Although Dr. Koprowski’s vaccine was never
adopted here, there is no question that he paved the way to the highly effective Sabin polio
vaccine by demonstrating the feasibility of this vaccine approach.
The success of the polio vaccine campaign in the US was due largely to the efforts of President
Franklin D. Roosevelt, who contracted polio as an adult and lost the use of his legs. He
established the National Foundation for Infantile Paralysis, later renamed the March of Dimes
Foundation, to finance the Salk and Sabin vaccines. Today, the two vaccines have eradicated
polio from most countries in the world. Only Afghanistan, Pakistan and Nigeria still harbor
transmission of the wild virus, and the number of new global cases fell to a record low of 223 in
2012, although there was a recently small polio outbreak in the horn of Africa. These impressive
results are due to a wonderful collaborative effort of the United Nations, governments,
foundations, businesses and Rotary International, which adopted this as a global cause (Rotary
has contributed hundreds of millions of dollars for polio eradication). The successful battle
against polio is an extraordinary example of what can be achieved through a cooperative global
effort.
Recently, I joined 450 scientists from 80 countries to offer support for a final push against polio.
The Global Polio Eradication Initiative involves a global public-private partnership that has
vowed to eliminate polio in six years at a cost of $5.5 billion. This will be achieved through
enhanced surveillance and vaccination strategies in affected countries. While the financial cost
may seem high to some, this is cheap compared to the costs of dealing with a polio resurgence.
It has been estimated that polio eradication efforts so far have saved more than 10 million
people from paralysis and saved over $40 billion in medical costs in some of the world’s poorest
countries.
Significant challenges remain in the countries where polio is still being transmitted. These
include the lack of effective public health systems, distrust of vaccination (including the murder
of volunteers administering the vaccine) and nomadic populations (which can serve as a viral
reservoir). But as stated by the Global Polio Eradication Initiative, “ending one of the world’s
most enduring diseases will create a ‘global public good,’ in that the benefits of a polio-free
world will extend to all children everywhere, in perpetuity, protecting them forever from this
debilitating, preventable disease.“
David L. “Woody” Woodland, Ph.D. is the Chief Scientific Officer of Silverthorne-based Keystone
Symposia on Molecular and Cellular Biology, a nonprofit dedicated to accelerating life science discovery
by convening internationally renowned research conferences in Summit County and worldwide. Woody
can be reached at 970-262-1230 ext. 131 or woody@keystonesymposia.org.
To view more (Petri) Dish articles, please visit “News” on the Keystone Symposia website.