Epidemic cerebrospinal meningitis is a communicable disease. Its cause, the Meningococcus intracellularis, although first described by Weichselbaum twenty years ago, was not generally recognized as such until the bacteriologic work of recent epidemics had been reported on.
Taking the epidemic of 1905 in the province of Upper Silesia in Germany as an example, described by Westenhoeffer,1 we find that 3,102 persons were attacked and that 1,789 succumbed in this epidemic. During its course von Lingelsheim made over 3,000 tests at the bacteriologic station at Beuthen and found the meningococcus in the mucus taken from the nasopharynx in 93.8 per cent. of the patients.
This coincides with the finding of Councilman, Mallory and Wright in American epidemics. Ninety per cent. of the patients were children under 15 years of age.
In twenty-four healthy relatives of the patients Ostermann2 found the meningococcus in the mucus taken from the nasopharynx seventeen