Jenner, cowpox, smallpox, and the first vaccine

arodri03 at arodri03 at
Wed Sep 13 22:57:22 EST 1995

Thank you for answering my post and bringing up an interesting angle about Jenner’s work.
Yes, I agree.  Mr. Benjamin Jesty and probably many other farmers of the area had performed 
successful vaccinations on themselves and members of their families in order to protect them from 
smallpox.  It was a popular believe among farmers, sustained by years of observation,  that when 
milkmaids were affected with cowpox, they wouldn’t get sick with smallpox. Jenner was aware of this 
fact  as were many other physicians of the area. Most of them thought that the farmers believe was 
people’s superstition. Jenner thought differently and repeatedly talked to his colleagues about it. 
Apparently he was so persistent that the local “Medical Society” threatened to expel him unless he 
stopped talking about it.
 I agree in that Jenner didn’t “discover” vaccination. That’s why I wrote in my first article: “... Jenner... 
demonstrated for the first time that it was possible to induce protection against a dangerous disease 
through immunization.”  I think his merit was to go one step forward and scientifically confirm the popular 
observations that a cowpox infection (mostly mild in humans) protected against  smallpox, a dangerous 
disease that killed about 40% of the infected people.  On May 14 1796  Jenner  did the following 
experiment.  He transferred “cowpox matter” from a pustule on the hand of the milkmaid Sarah Nelmes 
to the arms of an eight-year-old  boy named James Phipps, who had never had smallpox . After 4-6 
weeks, Jenner  transferred  “smallpox matter” to the boy and observed him for a few weeks for the 
appearance of smallpox signs.  James Phipps did not get smallpox. Jenner inoculated him for a second 
time with “smallpox matter”, and Phipps did not get sick  with smallpox. After James Phipps, Jenner 
vaccinated many others with “cowpox matter”, and challenged them with smallpox. Neither of them got 
sick with smallpox. 
On 1796 Jenner scientifically demonstrated for the first time what farmers already knew for a long time.  
A mild cowpox infection will protect against smallpox, the “red death”.  Jenner’s  demonstration was 
followed by lots of controversy, until these days, but also was the beginning of the long way toward the 
eradication of smallpox, the birth of Immunology, and the development of many other vaccines used 
Finally, I think Jenner deserves recognition for his drive and perseverance in standing up for 
vaccination during years of attempts to discredit or deny the value of the procedure.

Ana Maria Soler-Rodriguez
arodri03 at

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