All infections, of whatever type, with no exceptions, are products of parasitic beings; that is, by living organisms that enter in other living organisms, in which they find nourishment, that is, food that suits them, here they hatch, grow and reproduce themselves.

But however secure and well-regulated civilized life may become, bacteria, Protozoa, viruses, infected fleas, lice, ticks, mosquitoes, and bedbugs will always lurk in the shadows ready to pounce when neglect, poverty, famine, or war lets down the defenses.

But when it has been shown by the researches of Pasteur that the septic property of the atmosphere depended not on the oxygen, or any gaseous constituent, but on minute organisms suspended in it, which owed their energy to their vitality, it occurred to me that decomposition in the injured part might be avoided without excluding the air, by applying as a dressing some material capable of destroying the life of the floating particles. Upon this principle I have based a practice.

I have shown first in the course of this investigation that the infective matter is independently animate, and further that one could think of the independently animate matter as either animal and plant organisms or elementary parts of animals, which have achieved a relative individuality.

No science is immune to the infection of politics and the corruption of power. … The time has come to consider how we might bring about a separation, as complete as possible, between Science and Government in all countries. I call this the disestablishment of science, in the same sense in which the churches have been disestablished and have become independent of the state.

Sepsis is an insult to a surgeon.

The frequency of disastrous consequences in compound fracture, contrasted with the complete immunity from danger to life or limb in simple fracture, is one of the most striking as well as melancholy facts in surgical practice.

The possibility that the infective agent may not contain nucleic acid and consist only of a peptide or peptide-polysaccharide complex which has replication properties within susceptible cells is intriguing. If peptides, short-chain proteins, or peptide/fatty-acid/ polysaccharide complexes activate nucleic-acid template activity in the host genes to produce identical infective particles, this would invalidate the accepted dogma of present-day molecular biology in which D.N.A. and R.N.A. templates control all biological activity.

The pure culture is the foundation for all research on infectious disease.

The sick are still in General Mixed Workhouses—the maternity cases, the cancerous, the venereal, the chronically infirm, and even the infectious, all together in one building, often in the same ward where they cannot be treated.

To choose a rough example, think of a thorn which has stuck in a finger and produces an inflammation and suppuration. Should the thorn be discharged with the pus, then the finger of another individual may be pricked with it, and the disease may be produced a second time. In this case it would not be the disease, not even its product, that would be transmitted by the thorn, but rather the stimulus which engendered it. Now supposing that the thorn is capable of multiplying in the sick body, or that every smallest part may again become a thorn, then one would be able to excite the same disease, inflammation and suppuration, in other individuals by transmitting any of its smallest parts. The disease is not the parasite but the thorn. Diseases resemble one another, because their causes resemble each other. The contagion in our sense is therefore not the germ or seed of the disease, but rather the cause of the disease. For example, the egg of a taenia is not the product of a worm disease even though the worm disease may have been the cause, which first gave rise to the taenia in the intestinal contents—nor of the individual afflicted with the worm disease, but rather of the parasitic body, which, no matter how it may have come into the world at first, now reproduces itself by means of eggs, and produces the symptoms of the worm disease, at least in part. It is not the seed of the disease; the latter multiplies in the sick organism, and is again excreted at the end of the disease.