Presentation Speech by Professor the Count K.A.H. Mörner, Rector of the Royal Caroline Institute, on December 10, 1905
Your Majesty, Your Royal Highnesses, Ladies
and Gentlemen.
The Staff of the Royal Caroline Institute takes great pleasure in
giving this year's Nobel Prize for Medicine to the man who takes
precedence among those now alive as a pioneer in bacteriological
research, the prize being awarded to Geheimrat Robert Koch for
his work and discoveries concerning tuberculosis.
This work comprises only part of his activities, through which he
has rendered such great, indeed unique, services to medical
progress during the last decades. Even if it is only the part
mentioned which is the object of this year's award, I must still
briefly enumerate the main features of his activities as a whole.
The meaning of his work on tuberculosis is brought out more
vividly and powerfully if this is seen in the context from which
it took its origin.
To make Koch's significance in the development of bacteriology
clear, one must take a look at the situation with which Koch was
confronted when he made his appearance. Pasteur had indeed already published by then his
epoch-making work, which laid the foundations of bacteriology,
and medical art had already gathered in one very beneficial fruit
which stemmed from this work, namely the antiseptic method of
treating wounds proposed by Lister. However,
the trail was yet to be blazed, which bacteriological research
has followed with such success during recent decades, to discover
the causes of individual diseases and to look for the means of
combating them. Koch was a pioneer in this.
For two diseases namely anthrax and typhus recurrens in which
micro-organisms of a particularly characteristic appearance were
relatively easy to demonstrate, it was agreed that the latter
were the causes of these diseases. Otherwise the causal
relationship between bacteria and diseases was obscure. It is
true that there were good grounds for supposing that
certain other diseases were caused by micro-organisms. But
detailed knowledge concerning this was lacking, and experimental
findings were very divergent. So, for instance, it was not
established whether normal healthy organs contained bacterial
germs. This was certainly contested by various prominent
investigators, but on the other hand this view was defended by
other also prominent authors. Then the question still remained
open of whether bacteria observed in a disease were also its
cause, or whether their development should rather be considered a
result of the pathological process. In addition, in studying one
and the same type of disease various investigators looked in vain
for bacteria in the organism, while others, however, found them.
Moreover, bacteria, which various investigators had observed in a
particular disease, were often of a different appearance, so that
there was reason for doubting that they were the specific and
genuine cause of the disease. On the other hand, in widely
differing types of disease, bacteria were met with which, as far
as was known, were of one and the same kind, and this gave still
more cause for adopting a position of doubt with regard to the
causal relationship between these bacteria and the pathological
process. It was indeed difficult to imagine that the bacteria
discovered had to be regarded as the essential causes of disease,
since it looked partly as if the same disease could be caused by
different bacteria, and partly as if the same bacteria could
produce different diseases. It was easier to suppose that the
bacteria all had the property of facilitating the development of
the disease by exercising an influence on the organism. The
uncertainty was that much greater since the experiments which
were carried out often could not demonstrate whether a real
bacterial invasion of the organism had taken place.
In 1876 Koch entered the field of bacteriological research with
an investigation of anthrax, and two years later he produced his
classical investigations into diseases from wound infections.
With the views set out there and the way he formulated the
questions, he had a fundamental effect on the further development
of bacteriology, and the ideas he expressed there recur as a
leading motive in his subsequent research and form the foundation
of modern bacteriology, as they do of the axioms of hygiene which
are derived from it.
He stressed that, if bacteria caused a disease, then they must
always be demonstrable in it, and they should develop in a way
such that this would account for the pathological process.
He further stressed that the capacity to produce disease could
not be a general property of bacteria or one common to them all.
On the contrary it should be expected in this respect to find
specific properties distinguishing individual bacteria. Even if
they resemble other bacteria in their form, etc. they must still
be different from one another by virtue of this biological
property: in other words, every disease must have its special
bacterium, and to combat the disease, it would be necessary to
look for clues in the biology of the bacterium. Koch therefore
not only set himself the task of examining the problem of whether
diseases were caused by bacteria, but also endeavoured to
discover the special micro-organisms of the particular diseases
and to get to know more about them: this was a problem which, in
the circumstances then prevailing, seemed to offer very little
hope of being solved. In the way Koch solved this problem he was
just as much, if not more, of a pioneer, then he already was in
the abovementioned precision which he had given to the
formulation of the problem.
To start with, developing a general methodology is as valuable as
finding the correct technique for every special case. Koch's
genius has blazed new trails in this respect and has given
present-day research its form. To give a detailed description of
this is beyond the scope of this account. I only want to mention
that he had moreover already given a significant development to
techniques in staining and microscopic investigation as well as
in the field of experiment in his earliest work. Shortly after
this he produced the important method, which is still generally
the usual one, of spreading the material under investigation in a
solid nutrient medium to allow each individual among the
micro-organisms present to develop into a fixed colony, from
which it is possible, in further research, to go on to obtain
what is known as a pure culture.
Shortly after the publication of his investigations into diseases
from wound infections Koch was appointed to the new Institution,
the «Gesundheitsamt» (Department of Health), in Berlin.
There he started work on some of the most important human
diseases, namely, tuberculosis, diphtheria and typhus. He worked
on the former one himself. The two latter investigations he left
to his first two pupils and assistants, Loeffler and Gaffky. For
all three diseases the specific bacteria were discovered and
studied in detail.
To give an account of the work which Koch carried out, or
accomplished through his pupils, and also to mention the work
which derives more indirectly from Koch, would nearly be the same
as describing the development of bacteriology over the last few
decades. I will content myself with naming some of the most
important discoveries and items of research which, in addition to
those already named, are more directly linked with Koch's name.
At the head of the German Cholera Commission Koch investigated
the parasitic aetiology of cholera in Egypt and India, and
discovered the cholera bacillus and the conditions necessary for
its life. Experience thus gained found practical application in
the development of measures taken to prevent and combat this
devastating disease. In addition Koch made important
investigations concerning plague in humans, malaria, tropical
dysentery, and the Egyptian eye disease (trachoma) among others,
and now finally concerning typhus recurrens in tropical Africa.
He has also carried out work of exceptional importance,
concerning a host of destructive tropical cattle diseases, such
as rinderpest, Surra disease, Texas fever, and finally concerning
coast fever in cattle and the trypanosome disease carried by the
tsetse fly.
Through the perfection he gave to methods of culturing and
identifying micro-organisms, he has been able to carry out his
work with regard to disinfectants and methods of disinfection so
important for practical hygiene, and advice concerning the early
detection and combating of certain epidemic diseases such as
cholera, typhus and malaria.
Now I move over to a brief account of the series of
investigations which is the object of the present award.
The idea that tuberculosis is infectious goes back a long way to
Morgagni. Already before Koch had started his investigations into
this disease, it had been possible to show that tuberculosis may
be inoculated into animals. It was not, however, proved that it
was caused by a micro-organism, and such an interpretation was
contested by very distinguished investigators.
Koch made his first communication concerning his research on
tuberculosis in a lecture given on March 24, 1882 to the
Physiological Society of Berlin. This lecture covers scarcely two
pages of print, yet in it are given the proofs of the discovery
of the tubercle bacillus and the description of its chief
characteristics. The method for staining it in the affected
tissue is described there, its constant occurrence in tuberculous
processes in man and beast is mentioned, the procedure for
producing pure cultures of it is described, and information is
given concerning typical and positive results of inoculating the
bacillus in animals. It was emphasized there, in addition, that
the bacillus is dependent on the living organism for its
development and multiplication, and that hence tuberculous
infection is derived primarily from the expectorations of
consumptives, and that it can probably also be caused by cattle
suffering from «pearl disease».
By this epoch-making discovery, which immediately established the
characteristic features of the bacteriology of tuberculosis, a
broad field for further research into this disease was disclosed.
Until recently Koch has continued his investigations into this
disease with his invincible enthusiasm for research, and has
endeavoured to solve the difficult questions which have presented
themselves. During the 1880's he was, however, hindered in this
for a long time by public duties. His next striking piece of work
appeared in 1890, when he published his investigations into the
effect which certain materials, so-called tuberculin, formed in
cultures of tubercle bacillus, have on the organism. They
provoke, that is, a strong reaction, which it was also intended
to use for therapeutic purposes. It is true that, as a cure for
tuberculosis, it did not live up to what was hoped of it, which
had been exaggerated out of proportion by the strong desire of
the public and probably also of doctors for a cure of this
disease. Despite all that, it has attracted attention again of
late, and, in the form in which it is now obtained, it is thought
that it can be used advantageously in the curative treatment of
tuberculosis; and for this purpose it has had an application,
albeit a limited one. It has continued to retain great importance
as a means of diagnosing tuberculosis in the early stages or in a
concealed form, and for this purpose it has an extensive
application in the struggle against tuberculosis in cattle. This
work has also been of great significance as a precursor to serum
therapy, which has been so successful in other fields.
Recently, in 1901 to be exact, Koch has added another sensational
link to the chain of his research on tuberculosis, when he
presented his findings concerning the relation between human and
bovine tuberculosis to the Congress on Tuberculosis in London. He
found that human tuberculosis could not, as a rule, be inoculated
into cattle, while they were very susceptible to bovine
tuberculosis. So he found a very noteworthy difference between
the tubercle bacilli of the two diseases. Experience at that
time, concerning the transmission of tuberculosis from cattle to
humans, gave Koch cause to consider bovine tuberculosis as being
of only quite secondary importance in the development of human
tuberculosis, whereas in this respect he strongly emphasized and
stressed the spread of tuberculosis between humans.
Koch's view that a definite difference existed between the
tuberculoses from the two sources named, and his opinion that
bovine tuberculosis was relatively harmless, met with strong
opposition, whereby a diametrically opposed viewpoint was also
strongly affirmed. Accordingly Koch's pronouncement caused a long
series of investigations. His observation on the low virulence of
human tuberculosis in cattle can now be considered established.
It has also been found that the difference goes further, when it
was found that there are certain typical dissimilarities with
respect to the way they grow, etc. between tubercle bacilli from
these two sources. In this way it was possible to approach, even
if not to give conclusively, the answer to the difficult question
of the possibility or frequence of transmission of bovine
tuberculosis to humans. The current position regarding this
question permits it to be answered for the present to the extent
that tubercle bacilli of the same sort as those in cattle have
indeed been found in humans, and seen to be present more often
than experience in 1901 gave reason to believe, and on this
account the matter must be given continued attention; however,
the number of cases in which such bacilli have been met with,
together with other observations, especially the frequency of
human tuberculosis in districts where bovine tuberculosis is
either lacking or infection of humans from this quarter can by
and large be ruled out, provide strong support for Koch's
conception of the dominant importance of infection from
one human to another in the spread of tuberculosis in humans.
Seldom has an investigator been able to
comprehend in advance with such clear-sightedness a new, unbroken
field of investigation, and seldom has someone succeeded in
working on it with the brilliance and success with which Robert
Koch has done this. Seldom have so many discoveries of such
decisive significance to humanity stemmed from the activity of a
single man, as is the case with him.
One series of studies by him - indeed one of the most important -
to which he has devoted a great part of his research from the
outset until recently, namely his investigations and discoveries
concerning tuberculosis, is singled out by the Professional Staff
of the Royal Caroline Institute, as witness of its homage, with
the award of this year's Nobel Prize.
Geheimrat Robert Koch. In announcing that
the Staff of Professors of the Royal Caroline Institute has
awarded you this year's Nobel Prize in Medicine for your work and
discoveries concerning tuberculosis, I bring you the Staff's
homage.
Only solitary instances occur of one person on his own making so
many fundamental and pioneering discoveries, as you have
done.
By your pioneering research you have found out the bacteriology
of tuberculosis, and written your name for ever in the annals of
medicine.
From Nobel Lectures, Physiology or Medicine 1901-1921, Elsevier Publishing Company, Amsterdam, 1967
Copyright © The Nobel Foundation 1905