SLEEPY SICKNESS

Hokitika Guardian, 26 January 1926, Page 1

SLEEPY SICKNESS

CARRIED BY CHANGEABLE GERA!

Tlie tiny organism that causes sleepy sickness, or encephalitis lethargiea, and lias mystified scientists since the first appearance of flic disease in Vienna during the world war, has at last been definitely tagged and identified by Miss Alice C. Evans, of the United States Hygienic Laboratory. The organism belongs to the streptococcus group of bacteria. It varies so greatly in size that it can pass through 'the finest filler devised by science, and yet it grows so large at other times that it can easily he seen with the ordinary miseroscope. The disease is not the same as the African “ sleeping sickness,” that is caused by an organism carried by the tsetse fly. Enccphaliti lethargiea has been thought by some scientists to bo due to the same organism that causes influenza, because it has followed infleunza epidemics. Miss Evans obtained the sample streptococci, with which she experimented, from the brain of a patient who had died of sleepy sickness at St. Elizabeth’s Hospital for the Insane at Washington. The organisms wore cultivated in test tubes and used to inoculate rabbits. The animals contracted the same disease, and after death the identical organisms were found in great quantities in the rabbits’ brains. The disease was given to oilier rabbits by means of germs recovered from, the brains of the ones that had died; this was continned until a succession of 17 rabbits had been killed by the descendants of the original streptococci taken from the brain of the human case.

The organisms aro not very hardy, and when kept for a long time under artificial conditions they lose virulence. Miss Evans also noted that wlu?n very small doses of strong sterptococci were injected into rabbits they did not contract the disease immediately, and when they did so it took a long time for thorn, to die. Tn other words, small doses gave them a partial immunity.