Alexander Fleming (1881-1955)

On streptococcal infections of septic wounds at base hospital.



alteration, if any, would result from prolonged cultivation on
artificial media, the strains which showed the widest varia-
tions were retested at subsequent dates. As mentioned
above, the various strains isolated were grown on agar
slopes, sealed with paraffin wax, and placed in the ice-
chest. They were subsequently subcultured on to further
agar slopes at intervals of six weeks, the fresh cultures, after
24 hours in the incubator, being preserved in the same way.

The original strain was tested on five batches of mice
between July, 1918 and February, 1919. On the first
occasion no mouse succumbed within 30 days. In the later
expriments a few mice died in each case. The highest
morality occurred in the last test carried out, when four of
eight mice died during the 30 days over which the experi-
ment continued. From only one of these mice, however,
was B. Danysz isolated. Moreover, the deaths, when they
occurred were irregularly distributed in time. On no occa-
sion were more than one mouse found dead on any one day.

The strain from the spleen of the mouse of Experiment 3 D
which was used in Experiment 4 a was retested on four
subsequent occasions between September, 1918, and February,
1919. In the first experiment 8 of 12 mice died within
30 days, a mortality of 66 per cent. In the second experi-
ment the mortality during the same period was 100 per
cent. In the three subsequent tests the mortality was 66,
66, and 62 per cent, respectively. Moreover, there was a
most definite time distribution. In each of the three earlier
experiments there was an incubation period of 12 to 15 days,
followed by an outbreak involving the death of a large pro-
portion of the mice within a few days. The difference
between the resuts of these experiments and those carried
out with the original strain were most striking when actually
observed On the last two occasions on which this strain
was tested the tendency to produce a series of deaths within
a short time interval and following a definite incubation
period seemed to have been lost.

Similarly, the strain labelled “Spleen 3 : 5 × : 9.12,”
which was employed in Experiment 6×7, was retested on
three occasions within the following two months. It
showed on the first three occasions a consistent tendency
to produce a high and early mortality. Thus all the mice of
the first experiment died within three days. All the mice
of the second experiment succumbed on the 6th day. Four
of six mice fed in the third experiment died on the 3rd day,
while a fifth died on the 16th. On the last retesting this
strain seemed to have lost its peculiar properties.

Two other strains which had shown particularly low
pathogenicity were subsequently retested, and the results
confirmed those originally obtained.

Thus two strains at least were evolved which possessed
quite definite infective properties. One tended to produce
an outbreak of disease after an incubation period of 12 to 15
days. The other led to the death of all the animals fed
within a few days. These properties were maintained for
weeks or months under artificial cultivation, but were
gradually lost, and when finally tested the strains were
indistinguishable from the original strain of B. Danysz.

No attempt was made to maintain the pathogenicity of the
cultures by special methods of cultivation and storage. The
exact combination of properties on which this pathogenicity
depended was a subject for surmise, but it was clearly
not simply a question of virulence in the strict conven-
tional sense. It seemed better, therefore, to rely on the
simplest methods of culture and observe any changes
which occurred.

The results of observations on the factors possibly con-
cerned in the loss of pathogenicity by passage, and especially
on the question of the spread of the infection from the mice
tea on cultures of the bacillus to their normal companions,
will be considered in my last lecture.

Bibliography.—Brainbridge: Journ. Path. and Bact., 1909, xiii., 443.
Billet, le Bihan and others: Arch. de Méd. et de Pharm. Milit.. 1910,
lv. 259. Brownlee: Trans Ray. Soc Med.(Epidem. Soc.) 1909, ii.
243. Bruns and Höhn: Klin. Jahrb. 1908, xviii., 285. Butler: Proc.
Roy Soc. Med. (Epidem. Sec. ) 1909, ii., 59. Chesney: Journ. Exp.
Med ., 1916,xxiv., 387. Danysz: Ann. de I’Inst Pasteur. 1900. xiv.
193. Flack: Med Res. ,Comm. Spec. Rept., Ser. No. 3,1917. Glover:
Journ. Hyg., 1918, xvii., 350, 367. Graham-Smith: The Bacteriology
of Diphtheria, Camb., 1908. Hutchens: Med. Res. Comm. Rept., 1916
Johnston: Med. Res. Comm. Spec., 1916. Köber: Zeitschr. f. Hyg.,
1899, xxxi., 433. Ledingbam and Arkwright: The Carrier Problem in
Infectious Diseases, Lond., 1912. Ledingham and Penfold : Journ. of
Hyg., 1914, xvi., 242. Liston: Rep. Bombay Bact. Lab., 1907. Mühlens,
Dahm, and Fürst: Centralb. f. Bakter. ü Parasitenk, 1909, Orig.,
xlviii., 1. penfold: Jorn Hyg., 1914, xiv., 215. Stillman: Journ.
Exp. Med., 1917, xxvi., 513. Wadsworth and Kirkbride: Journ. Exp.
Med., 1918, xxviii., 791.






         A. B. PORTEOUS, M.B., B.S. LOND.,


IN connexion with streptococcus infections of wounds at
base hospitals there are certain questions which are of funda-
mental importance.

What are the Types of Streptococci that Require to be
Seriously Considered in Wound Infections ?

There is one type of streptococcus which is predominant
in septic wounds at the base. This type is responsible for
almost all the severe septic complications of these wounds.
It is to be found in pure culture in nearly all the infected
joint cavities and fresh pockets of the wounds, and in our
experience it has been responsible for all the streptococcal
septicæmia following septic wounds.

Characters of this streptococcus.—It grows in broth in long
chains of regular cocci. Some strains after 24 hours show
very marked involution forms, the cocci being all shapes and
sizes. The culture in broth consists of small woolly masses,
which settle to the bottom of the tube (or along the side of
the tube if it is incubated in a slanting position), leaving
the upper portion of the medium clear. On agar (Douglas’s
trypsin agar) it grows well in moderate-sized colonies, which
show by transmitted light a definite dark central portion,
while the edges are slightly wavy and irregular. It does not
liquefy gelatin. This streptococcus always grows better
anaerobically, and not infrequently when first isolated it will
not grow aerobically. After being cultivated for a short
time, however, it grows freely under aerobic conditions. It
is not constant in its sugar reactions. In the great majority
of cases it ferments glucose, lactose, saccharose, and salicin,
but not raffinose, mannite, or inulin. A few strains, however
(about 12 per cent.), ferment mannite. These mannite-
fermenting strains are identical morphologically with the
non-mannite fermenters, and it has been shown by Douglas,
Colebrook, and Fleming, in a report to the Medical Research
Committee not yet published, by means of agglutination and
absorption tests that serologically they are also identical.

Clotting of milk.—This test is very inconstant, and we have
found that as regards the clotting of milk with these strepto-
cocci very much depends on the size of the tube in which the
test is carried out. If the tube is of large size then the
clotting is always delayed and it may even not take place in
ten days, whereas in a small test-tube there is definite clotting
in 24 hours. In a series of tubes of different sizes containing
milk which had been heavily implanted with Streptococcus
and incubated for five days it was observed that no
clotting had occurred in the two largest tubes, in the third
tube clotting bad occurred but there was no contraction of
the clot, while in the smallest tube there was firm clotting
with much contraction of the clot. This clotting of the
milk in the smallest tube had occurred in the first 24 hours.
Even in small tubes, however, the clotting of milk by Strepto-
coccus pyogenes
is quite inconstant and is worthless as a

Hæmolytic power.—All the strains of this streptococcus
showed some hæmolytic power, but there seemed to be
enormous differences in the amount of hæmolysin produced
under the same conditions by streptococci which were
isolated from the blood of septicæmic patients. In a number
of cases the hæmolytic power was tested by centrifuging a
broth culture and incubating for two hours at 37° C. dilutions
of the clear supernatant fluid with washed human red
corpuscles. In most cases, however, the question of whether
these streptococci were hæmolytic or not was tested by
noting the appearance produced by their growth on a blood
agar plate (see Fig. 2).

Incidence of this streptococcus.—In a series of over 100
septic wounds (fractured femurs) which had remained at a
base hospital for over seven days this streptococcus was
present in almost every one. In cases of a similar nature
where streptococci were recovered from the blood (47 cases)
the organism was invariably of this type

                                    B 2