10 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 
It most frequently breaks out in huts and barracks where 
soldiers are crowded together without sufficient ventilation. 
A remarkable feature of all epidemics of this disease, and one 
which makes it exceedingly difficult to deal with, is the fact 
that healthy persons who have been in contact with cases of 
cerebro-spinal meningitis frequently carry the germs im the 
back of their nose; although they may not themselves 
contract the disease, they may infect other more susceptible 
persons. Consequently, whenever a case of cerebro-spinal 
meningitis occurs among soldiers, all those who have been in 
contact with the patient are isolated and their nose examined 
by a bacteriologist to ascertain whether they are free from 
the coccus. 
Last spring, there were several fatal cases of cerebro-spinal 
. I examined 195 
contacts and found about four per cent. of apparently healthy 
meningitis in a certain barracks at P 
men were “ germ carriers.” They were of course kept in 
quarantine and their nose treated with antiseptics till the 
germ was killed. The problem which the Military Authorities 
have had to face can be gathered by the followmg figures. 
There were 279 cases among the civil population of England 
and Wales in 1913, and 300 in 1914, but in the first six months 
of 1915 there were 2,290 among the civil population and 1,088 
among the troops quartered in this country. The mortality 
was about sixty per cent.* 
PLAGUE. 
The black death which overran Europe in the Middle 
Ages, and later slew 70,000 of the inhabitants of London in 
the reign of Charles II., almost disappeared from the civilized 
world during the 18th and 19th centuries, although it slumbered 
in the Far East. In 1894 a great outbreak occurred in Hong- 
* Reece, R. J., Journ. Roy. A. Med. Corps, June, 1915, p. 555. 
