[Translated for The Journal.]
1. It is not uncommon to see two different species of microbe invade at the same time an animal organism; the result of this mixed infection may be widely dissimilar. Sometimes the two pathogenic agents develop side by side, without any reciprocal influence upon each other; sometimes the animal will find in one of them an unexpected ally against the other, when it would have succumbed to the one affection, it survives the combined attack of the two; finally the two microbes acting together sometimes overcome an organism which would have resisted successfully either one of the invaders, if attacking alone. It is this last group which is reviewed by the Gazette. The writer remarks that it is the result most frequently seen; almost always infection intensifies infection.
It is not necessary that the two microbes both be pathogenic in order that their results
BOUCHARD C. THE HISTORY OF MICROBIAN PRODUCTS WHICH FAVOR INFECTION.. JAMA. 1890;XV(9):320-324. doi:10.1001/jama.1890.02410350016001d