View report page

10
or B. Hoffmanni only. 310 detailed examinations were made of cultures from the throat or nose originally
reported suspicious: in 47 of these the K.L.B. were isolated and in the remainder only diphtheroids or
B. Hoffmanni were obtained in sub-culture. Twenty-two examinations were made of cultures from the
ear in cases of discharging ears, but in no case was true morphological K.L.B. isolated, the majority
yielding diphtheroid organisms. A case of conjunctivitis and one of whitlow also yielded diphtheroid
organisms only. In addition to isolating the K.L.B. and bacilli belonging to the diphtheroid group useful
confirmatory biochemical tests were applied to a large number of the strains, involving sub-culture in
tubes containing Hiss' fluid serum with glucose, saccharose and dextrin, respectively, and blue litmus
to indicate fermentative changes.
B. Diphtheriæ ferments glucose and dextrin-with production of acid, but causing no change with
saccharose, whereas a common diphtheria organism, such as B. Xerosis, produces acid in the glucose and
saccharose but not with dextrin, and B. Hoffmanni the commonest of the diphtheroids fails to change any
of the three. The isolated cultures of K.L.B. obtained in 334 separate examinations of 246 cases were
sent to the Wellcome Research Laboratory for virulence tests with the following results.
Examinations Cases.
K.L.B. virulent in 205 158
K.L.B. avirulent in 129 88
including 5 cases in which the original cultures were found to be virulent in 9 examinations and later
cultures avirulent in 11 examinations. In addition to the cultures of morphological K.L.B. 54 cultures
of diphtheroid organisms from the throat and nose and four from the ear (from 65 cases) were also sent
for virulence testing and in every instance proved avirulent. The total number of strains of diphtheria
bacilli and diphtheroid organisms tested for virulence between April, 1921, and March, 1922, amounted
to 397 from 304 cases.
In 230 of the 246 cases in which the K.L.B. were tested for virulence particulars were stated—
concerning abnormalities of the throat, nose or ear; history of sore throat or other illness; history of sore
throat or diphtheria carriers in members of the family or contact with cases of diphtheria.. 140 out
of the 230 belonged to the first of these categories, those showing various abnormalities, e.g., tonsillitis,
enlarged, unhealthy or congested tonsils, congested fauces or uvula, pharyngitis, nasal discharge,
excoriation of the nasal passages, nasal crusts, or adenoids. The diphtheria bacillus was virulent in
90 of these and avirulent in 50.
Analysis of the other conditions showed as follows:—
K.L.B. virulent
K.L.B avirulent
History of sore
throat or
cold.
21
13
History of having
been in hospital
with diphtheria.
10
2
Family history
of sore throats or
carriers.
7
0
Contacts of
cases of
diphtheria.
23
7
No history obtained
as to contact with
infection. No
defects recorded.
19
10
Diarrhœa
and
Enteritis.
There were 2,152 deaths among children under two years of age from diarrhoea and enteritis in
London in 1921, giving a mortality rate per thousand births of 21.55; this rate is in excess of that for the
four preceding years, but is very slightly below the average for the ten years 1911-1920. In view of the
high average temperature of the summer, the mortality from infantile diarrhoea was remarkably
low. The relationship between summer temperature and diarrhoea mortality has been the subject
of much study. From the earliest days of death registration the London records have shown so
close a dependence of diarrhœal mortality upon the excess or deficiency of summer temperature that it
has been possible until recent years to deduce from the temperature records for a given summer the
approximate total deaths from summer diarrhœa. In order to determine how far the relatively low mortality
from summer diarrhoea of recent years results from reduced temperature, or is due to other circumstances,
the relationship between the deviations from normal of temperature and summer diarrhœa
mortality among infants under one year of age, has been calculated from the records of the years 1881—
1900, and the results have been applied to the period 1876-1921. The actual and the calculated deaths
for a period including the summer months (July, August and September) of each year are shown at the
foot of the diagram on page 9. It will be seen that for the thirty-eight years up to 1914, the calculated
deaths are in very close agreement with the numbers recorded; the agreement is indeed remarkable when
regard is had to changes in classification which occurred in the course of the period, more especially late in
the nineties. In 1914, and subsequent years there is a remarkable difference between the actual and estimated
mortality, and as this takes in the whole of the war period, the probability that the conditions
brought about by the war have been responsible for the reduced mortality at once suggests itself. There
will, however, be found some indication in the diagram that the change which appears at first sight to
have occurred abruptly in 1914, is really foreshadowed some years earlier. Up to 1905, the actual
deaths are sometimes below and sometimes above the number calculated from the temperature; but
after 1905, with the exception of 1913, the calculated deaths always exceed the actual number, and the
excess in 1912 (a wet summer), was actually greater than in 1914. Again the excess in 1914 can scarcely
be attributed to war conditions in any large measure, even taking into account the fact that most of the
deaths occurred in September; in the earlier months of the war there was no scarcity of food, and
therefore no great change of diet affecting infants although the immediate increase in the price of sugar
may not have been without its effect upon the feeding of children of the poorest classes. The period
1916-19, is that in which the effects of the war would be expected to be most apparent, and although the
divergence of the calculated from the actual mortality in this period is very conspicuous, it is just as
apparent in the two succeeding years. There is no doubt that the separation allowances made during
the war, combined with the rationing of food, improved the quality and also even the quantity of food
supply of the very poor, of the class that is in which the mortality from infantile diarrhœa is greatest.
In addition there have been the special administrative measures, directed to the care of expectant and
nursing mothers, as well as of their infants; these were inaugurated before the war, and were further
developed in spite of war conditions. Over and above these direct influences upon child welfare, there is