THE MENINGOCOCCUS GROUP 335 
rate, respectively, and a local, excessive carrier rate where groups of 
people, as masses of troops, are brought together in inadequately 
spacious quarters. The incidence of carriers in overcrowded military 
quarters usually increases more rapidly and reaches greater proportions 
than is the case in epidemic periods in normal civic life. This is largely 
due to the notorious overcrowding inseparable from active military 
operations. 
Cerebrospinal meningitis appears to have been unusually prevalent 
among the soldiers during the Civil War in the United States, and in 
other wars of magnitude where large numbers of men are mobilized 
and garrisoned in crowded quarters. The disease is less prevalent 
among the civil population. 
The Treatment of Meningococcus Carriers.— The meningococcus 
possesses but slight resistance to environmental influences, as exposure 
to light, desiccation and cold. The transfer of the organism from the 
nasopharynx of one host to the nasopharynx of another host is, so far 
as is known, by droplet infection. The infected droplets are minute, 
as a rule, and offer a large surface in proportion to their voliune; con- 
sequently, the two factors of drying and rapid lowering of temperature 
to a point where the organism is injured are potent in restricting the 
area which a carrier can cover by infective droplets. It is very prob- 
able that warm, crowded spaces are more dangerous than cold crowded 
spaces, within limits, for this reason. 
Attempts have been made to disinfect meningococcus carriers. 
The principles involved have been either to bring droplets of disin- 
fecting solution to the nasopharynx (which is the site of lodgment of 
sputum infected with meningococci), by atomizing some form of 
relatively atoxic disinfectant, as dichloramin-T, upon the nasopharyn- 
geal mucosa, or to wash the infected mucosa with some suitable 
solution. Both methods have apparently some direct, antagonistic 
action upon the organism, the latter being somewhat more effective 
than the former. In either case, success depends quite largely upon 
the thoroughness with which the process is carried out. For large 
numbers of carriers and carrier suspects, special chambers have been 
proposed, into which the disinfecting solution can be blown as a 
vapor or mist, after a proper number of subjects have been admitted. 
The subjects are instructed to inhale deeply and vigorously. The 
deep inhalation of the vapor through the nose reduces the num])ers 
of meningococci, temporarily at least, to a minimum. Catarrhal 
inflammaticm of the nasopharynx, adenoids or polypoid growths 
proba})ly reduces the efficiency of the process very materially. The 
degree of success attained thus far in the sterilization of meningococcus 
carriers is, on the whole, unsatisfactory, but somewhat promising. 
Types or Groups of Meningococci. Parameningococci. — Com])ilation of 
statistics upon the therapeutic use of antimeningococcus serum in 
the treatment of cerebrospinal meningitis has revealed a small group 
of cages which have either failed to respond favorably to injections 
