... After it has been determined that the pathogenic organism is present in the animal body, and after it has been shown that the organism can reproduce in the body and be transmitted from one individual to another, the most important experiment remains to be done....to determine the conditions necessary for growth and reproduction of the microorganism.
Robert KochIn view of the epidemiological situation in Germany, the lack of evidence for the effectiveness of the BCG-vaccine and the not uncommen severe, undesired side-effects of the BCG vaccine, the STIKO can no longer support the recommendation for this vaccination.
Robert KochFrom my numerous observations, I conclude that these tubercle bacilli occur in all tuberculous disorders, and that they are distinguishable from all other microorganisms.
Robert KochHowever, on many occasions, I examined normal blood and normal tissues and there was no possibility of overlooking bacteria or confusing them with granular masses of equal size. I never found organisms. Thus, I conclude that bacteria do not occur in healthy human or animal tissues.
Robert KochOur studies have shown that all cases of typhoid of this type have arisen by contact, that is, carried directly from one person to another. There was no trace of a connection to drinking water.
Robert Koch... After it has been determined that the pathogenic organism is present in the animal body, and after it has been shown that the organism can reproduce in the body and be transmitted from one individual to another, the most important experiment remains to be done....to determine the conditions necessary for growth and reproduction of the microorganism.
Robert Koch