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On the Value of Vaccination and Re-vaccination .* 
In 1842 the Academy of Sciences offered a prize for the best 
treatise on the above subject. Thirty-five candidates responded to 
the call ; and the perusal of their labours has proved so laborious an 
undertaking, that it is only very lately that M. Serres has been 
able to present a report to the Academy in the name of the com- 
mittee appointed to decide on the comparative merit of the essays. 
M. Serres’ report is a remarkable document, and is also important, 
from its conclusions having been adopted by the Academy after 
mature deliberation. We extract the following data from this 
report : — 
“ Vaccination preserves the human species from variola, but its 
preservative power is not absolute. Variola itself, either spontane- 
ous or produced by inoculation, does not preserve absolutely from 
future attacks, therefore it is not extraordinary that vaccination 
should not. Thus, Mead mentions having seen three variolous 
eruptions take place successively on the same woman : the son of 
Forestus was twice attacked with variola ; and Dehaen states that 
one of his patients was attacked six times by variola with im- 
punity, but died of a seventh invasion of the disease. Although, 
however, vaccination is sometimes powerless to preserve us from 
variola, it always diminishes the gravity of the latter malady. This 
property, which Jenner and his first successors did not even suspect, 
is thoroughly proved by the various facts which have been recently 
accumulated. In one of the most terrible epidemics of variola that 
has taken place in Europe since the discovery of vaccination, — that 
of Marseilles, in 1828, — more than ten thousand persons were at- 
tacked. Of these, two thousand only had been vaccinated, and of 
that number forty-five only died ; whereas one thousand five hun- 
dred of the eight thousand who had not been vaccinated were 
carried off by the pestilence. 
“ Vaccine matter evidently loses part of its efficacy in passing 
from arm to arm ; it is therefore desirable to renew it as often as 
possible. A remarkable fact mentioned by one of the competitors 
supplies us with a means of renewing it, as it were, at will. A 
cow was vaccinated with matter taken from a child. Not only did 
the pustules rise, but they were communicated to other cows, so 
that the cow-pox was observed nearly in its natural state. The 
pustules were identical in both cases. 
“ The propriety of re-vaccination is now fully established. In 
Germany, the various governments have been induced to pay 
* This was found among the late Mr. Youatt's papers. 
