Swine Erysipelas. 141 
and after an interval with a stronger one. It is also as yet 
impossible to say how long the immunity conferred by the 
operation will last, and it may be found that a life-long 
protection is unattainable except by vaccination repeated 
yearly or at longer intervals. Finally, it is possible that 
injection of the vaccin into the veins is not necessary, and that 
immunity can be conferred by introducing the bacilli under 
the skin. 
It is perhaps well to point out that, even if the vaccination 
realises the hopes which at present appear to be justified, it will 
still be necessary to continue some of the precautions which 
are imperative when it is desired to prevent the spread of 
tuberculosis in a herd. It appears to be established by the 
experience already gained that the full effect of the vaccination 
is not obtained until about three months after the operation, 
and therefore during that period the vaccinated animals ought, 
as far as possible, to be secluded from the risk of contagion. 
There is also little prospect that the vaccination will have any 
useful effect on an animal which is already infected ; and, for 
both these reasons, a preliminary test with tuberculin will be 
necessary before proceeding to vaccinate any lot of animals, 
all those that react being rejected as unsuitable for the opera- 
tion, and dangerous if left with the others. 
Although there is every reason to believe that a healthy 
animal of any age can by this method be protected against 
tuberculosis, it will probably in practice be best to attempt the 
eradication of the disease from a herd by systematically 
vaccinating the young animals within a few weeks or months 
after birth. By so proceeding it may be possible in the course 
of a few years, with a very moderate amount of trouble 
and expense, to free even a badly infected herd from the 
disease. 
Swine Erysipelas. 
A certain amount of alarm, not unreasonable in the 
circumstances, was caused during the past summer and autumn 
by reports regarding outbreaks of what was represented to be 
a new disease of pigs in Cambridgeshire. It was soon 
ascertained, however, that this disease was the one which 
during recent years has come to be known under the name, 
swine erysipelas. It is certainly not a new disease in England, 
and it is quite possible that it has been much longer in 
existence in this country than the more serious and better- 
known swine fever. Until about fifteen years ago, however, 
it was unrecognised in Great Britain as a distinct disease of the 
pig, the custom being to regard it as a variety of swine fever. 
It was the application of the methods of bacteriology which 
