Along with Albert Sabin's later oral live-virus version, the Salk vaccine
made it possible to conquer this dreaded disease in every country of the Americas (see sidebar p.
 Half of the participating children were selected at random and injected with the Salk vaccine
.  The other half of the subjects were injected with a placebo, a saline solution designed to have no medical effect whatsoever.
Redefinition of an epidemic: More cases were required to refer to polio as an epidemic after the introduction of the Salk vaccine
. In other words, you needed 20 cases per hundred thousand to have an epidemic before the vaccine was introduced, and after the vaccine, they changed that number to 35 cases per hundred thousand per year to require the definition of epidemic.
However, the Salk vaccine
consisted of dead virus that had to be injected, and whose ability to stimulate antibody production might not be long-lasting.
The introduction of the Salk vaccine
in the late 1950's was a historic and truly wonderful achievement.
When such a vaccine does arrive, dental caries may be eliminated, just as the Salk vaccine
has nearly eradicated polio.
In 1954, the first mass inoculation of schoolchildren against polio using the Salk vaccine
began in Pittsburgh as some 5,000 students were vaccinated.
As for the Salk vaccine
for poliomyelitis, developed in the 1950s, medical research has thankfully moved on since then with the test tube gradually replacing the laboratory mouse.
Then, in 1955, the Salk Vaccine
(inactivated Polio virus/attenuated live virus) was discovered as a prophylactic treatment.
Despite the Salk vaccine
and involvement of then MP for Coventry North, Maurice Edelman, the event proved how hard it can be to bring polio under control.
She appeared on television to promote vaccinations and her campaign became so successful that extra supplies of the Salk vaccine
had to be imported to the UK from America.