Discovery of The Vector
Nicolle's discovery came about first from his observation that, while epidemic typhus patients were able to infect other patients inside and outside the hospital, and their very clothes seemed to spread the disease, they were no longer infectious when they had had a hot bath and a change of clothes. Once he realized this, he reasoned that it was most likely that lice were the vector for epidemic typhus.
In June 1909 Nicolle tested his theory by infecting a chimpanzee with typhus, retrieving the lice from it, and placing it on a healthy chimpanzee. Within 10 days the second chimpanzee had typhus as well. After repeating his experiment he was sure of it: lice were the carriers.
Further research showed that the major transmission method was not louse bites but excrement: lice infected with typhus turn red and die after a couple of weeks, but in the meantime they excrete a large number of microbes. When a small quantity of this is rubbed on the skin or eye, an infection occurs.
Read more about this topic: Charles Nicolle
Famous quotes containing the words discovery of the, discovery of and/or discovery:
“Next to the striking of fire and the discovery of the wheel, the greatest triumph of what we call civilization was the domestication of the human male.”
—Max Lerner (b. 1902)
“That the discovery of this great truth, which lies so near and obvious to the mind, should be attained to by the reason of so very few, is a sad instance of the stupidity and inattention of men, who, though they are surrounded with such clear manifestations of the Deity, are yet so little affected by them, that they seem as it were blinded with excess of light.”
—George Berkeley (1685–1753)
“The discovery of Pennsylvania’s coal and iron was the deathblow to Allaire. The works were moved to Pennsylvania so hurriedly that for years pianos and the larger pieces of furniture stood in the deserted houses.”
—For the State of New Jersey, U.S. public relief program (1935-1943)