-- James Donald writes:
The original vaccine was based on cowpox, the nearest relative of small pox. However it was insufficiently effective and reliable, and so was furtively replaced by a weakened strain of smallpox, which was grown on cows. The sellers of the vaccine continued to represent it as cowpox, but it was in fact a mild variant of the real thing, smallpox.
One reason for ending routine smallpox vaccinations was fear that the vaccine might re-evolve virulence.
On 27 Sep 2001, at 21:50, Nomen Nescio wrote:
You are full of shit. The smallpox vaccine is not made from cowpox or from smallpox (variola) virus. It is made from the vaccinia virus. Did you ever wonder where the word "vaccine" comes from?
From the latin word for cow.
The vaccinia virus is most plausibly a weakened strain of smallpox. The word "vaccine" does not come from "vaccinia". On the contrary, the word "vaccinia" comes from "vaccine". The Vaccinia virus is intermediate between the cowpox and smallpox virus. It may be the result of hybridization between cowpox and smallpox, but is most plausibly the result of the small pox virus devolving back towards the cowpox virus from which it arose, as a result of being cultured in cows. In this sense, the vaccinia virus is most plausibly a weakened strain of smallpox. The word "vaccine" comes from cow, because the original vaccine was cowpox, and the current vaccine is raised in cows. --digsig James A. Donald 6YeGpsZR+nOTh/cGwvITnSR3TdzclVpR0+pr3YYQdkG xmLTZdHfPaan7hiLpGP6kvXloZVpeWslAvtwgk+J 4gbtIJ3SIp0x8Xj/mS0UM2vOtaTm2CXVbKuE5Onsv