In article <travers-1309950927230001 at macmhc.cryst.bbk.ac.uk>,
travers at europa.lif.icnet.uk (Paul J Travers) wrote:
> Ana Maria,
> don't forget the prior technique known as variolation, where protection
> from smallpox was sought by inoculating a small amount of smallpox virus.
> This was current in Britain shortly before Jenner's observations on cowpox
> and has a very long history. I believe there are reports from China
> dating back over 1000 years of dried crusts of smallpox lesions being
> used, perhaps an early attempt at attenuation or inactivation of the
> virus.
> The earliest reports of variolation that I have read of were in the
early centuries of this millenium, but in India, not China. Variolation
had been imported into Europe in the century prior to Jesty/Jenner, and as
it was the subject of a vigorous debate in England, it is fair to assume
that it may have affected the thinking of either or both.
However, to give Jenner his due - although the man may have been a
political opportunist, he is still the man who pushed vaccination into the
limelight and suggested a rationale that led to vaccination's testing and
validation. No mean achievement considering the vilification he initially
received and the competition from hordes of quacks pushing their own
patent remedies.
Finally, it is important not to focus our own ideas backward onto the
past. Variolation does not seemed to have been practised as an early form
of vaccination as we think of it (ie an attempt to prevent disease).
Given the lack of statistics and the fact that the mortlaity of
variolation could range up to 10-15 %, it is unlikely that the practioners
saw much difference in safety between variolation and the normal disease.
The big difference was that the variola lesion was given on the leg or the
arm - where the sacrring could be covered. Variolation seems to have been
inspired by the thinking "Well, you'll get it anyway, better you should
get it on the arm than the face". In other words it was intended merely
to prevent disfigurement - not disease. I have seen suggestions that the
pratice was more commonly practiced on women than men, which would agree
with that.
The Israeli army and Iraqi armies offer a similar form of "preventive
infection" with leishmania to troops sent to endemic areas in an attempt
to avoid disfiguring and more dangerous facial infections. Iraqui
peasants in some areas also expose the limbs of children hoping to
generate the initial infection away from the face.
Cheers, Mark