Vaccine

A vaccine is an antigenic preparation used to produce active immunity to a disease, in order to prevent or ameliorate the effects of infection by any natural or 'wild' strain of the organism. The term derives from vaccinia, the infectious viral agent of cowpox, which, when administered to humans, provided them protection against smallpox. The process of distributing and administrating vaccines is referred to as vaccination.

Origin of vaccines

In 1796, during the heyday of the smallpox virus in Europe, an English country doctor, Edward Jenner, observed that milkmaids would sometimes become infected with cowpox through their interactions with dairy cows' udders. Cowpox is a mild relative of the deadly smallpox virus. Building on the foundational practice of inoculation, Jenner took infectious fluid from the hand of milkmaid Sarah Nelmes. He inserted this fluid, by scratching or injection, into the arm of a healthy local eight year old boy, James Phipps. Phipps then showed symptoms of cowpox infection. Forty-eight days later, after Phipps had fully recovered from cowpox, Jenner injected smallpox-infected matter into Phipps, but Phipps did not later show signs of smallpox infection.

Related Topics:
1796 - Smallpox - Edward Jenner - Cowpox - Inoculation

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