View report page

3
Dr. Smith's inference, therefore, that "infection occurred 2, 3 or 4 days after the children's last
attendance at the school, and therefore indisputably outside the schools" falls to the ground.
Examination of the dates of attack shows that in each instance infection of the households in question
occurred (allowing for period of incubation) at a time antecedent to the beginning of the school
holidays.
3. Dr. Smith then further discusses the tables which he appends to his report. There are a number
of differences in detail between Dr. Hamer's notes and the statements in Dr. Smith's tables. Perhaps
the most important differences relate to table D. Dr. Smith bases upon this table the statement that
25 children "who had attended no school at all within seven days of attack were the first victims within
their respective families." In addition to differences as to detail above referred to, it should be noted
that these 25 cases are obtained by dealing with a longer period of time than that taken by Dr. Hamer,
and with the much larger area of "the parish of Lewisham and its immediate vicinity," whereas
Dr. Hamer's figures are obtained from cases occurring in the smaller "affected area." Again, Dr. Smith's
tables only include cases which were notified. Dr. Hamer supplemented the information supplied by
the notification lists by inquiry at the homes, and as the result of this inquiry has treated as
" secondary cases " several which in Dr. Smith's tables appear as cases occurring in houses in which
a previous case had not occurred.
4. Dr. Hamer has pointed to coincidence in point of time between the decrease in the number of
children attending the Board school and the decrease in the number of primary attacks in the affected
area. Dr. Smith publishes two tables (Tables IV. and V.) to show that the decrease in the number of
attacks (first sufferers) among children in the boys' department occurred at a time when the decrease in
the average attendance in this department had only fallen 10 per cent, and that there was an increase
in the number of attacks (first sufferers) in the infants' department after the fall in average attendance
had commenced. Dr. Hamer did not of course propose to suggest that there were precise
proportions between variations in average attendance from week to week and attack rate, but only to
show the general agreement in point of time between the falling off in the attendance at school and
the decrease in the number of houses newly invaded by diphtheria in the "affected area."
5. On page 6 Dr. Smith states "It is to be noted further that the closure of the boys' department
could only affect the scholars in attendance in that department, and not, as is implied, the infants and the
girls; for the reason that the boys' department occupied premises on one side of the road, the girls' and
infants' premises being on the other side, thus practically constituting two separate schools."
In inquiry into the effect of school attendance and school closure upon the occurrence of
diphtheria, it is proper, and indeed necessary, to take into account indirect as well as direct influence.
The attendance of one child out of a family at an infected school has a bearing upon the safety of the
rest of the family who attend other schools, differing in degree only from that of the reversed condition
in which a child from an infected house attends a school. All authorities are agreed that in the latter
instance the public safety is endangered by continuance of communication between school and infected
home, and steps are taken to put an end to it. Similarly the closure of an infected school must be
regarded as conferring some degree of safety upon children attending other schools from homes sending
children to the 3chool which is to be closed. In his statement above Dr. Smith omits consideration
of the fact that the boy who contracts diphtheria in the boys' department may by infecting his
sister who is attending the girls' department, or his younger brother or sister attending the infants'
department, introduce diphtheria into these latter departments.
6. On pages 7, 8 and 9 of his report Dr. Smith comments on the fact that certain children
attended school on days " subsequent to the first symptoms of their illness " without such attendance
being productive of disease in other children. I may mention that Dr. Hamer's knowledge of the
cases cited leads him to different conclusions as to these cases, but the matter as affecting the
results of Dr. Hamer's inquiry need not be discussed here, for it will hardly be contended that
the negative evidence that certain children suffering from diphtheria attended school without obvious
injury to other children is reason for setting aside the positive evidence which the history of the outbreak
supplies.
7. Dr. Smith finds, as the result of examination of the dates of first symptoms, and of last
attendance at school in the different classes, that of 137 cases inquired into, there are 116 "cases in
which the evidence excludes the school as the source of infection," and that in 21 cases the " evidence
as to school or non-school infection is insufficient." It may be pointed out—
(i.) That Dr. Smith ascertains in what number of instances a child attacked by
diphtheria was in attendance in a class or class-room in which a known previous sufferer had
been in attendance within the period of incubation of the disease. These cases Dr. Smith
groups under the heading " cases in which the evidence as to school or non-school infection
is insufficient."
(ii.) That in those instances, on the other hand, in which the sequence of events above
referred to was not observable, Dr. Smith, with two or three exceptions to be immediately
referred to, groups the cases under the heading " cases in which the evidence excludes the
school as the source of infection." These headings are misleading. The first heading really
includes the cases in which the evidence (so far as it goes) is of a positive character; the
second heading, those in which it is of a negative character, but, judging by the words
Dr. Smith employs, it might be inferred that the reverse was the case. It is necessary to
realise that where Dr. Smith says the evidence is insufficient, the evidence available points to
the school as the source of infection, and that where he says the evidence excludes the school,
he, as a matter of a fact, in the majority of cases, merely means that he has not been able to
show, with regard to an individual sufferer, that he or she was exposed to a recognised source
of contagion in the class-room attended by that sufferer. The exceptions referred to above
are found in one case in the St. Mary National School, one case in the girls' department of
the Board school, concerning which (par. 1 on page 7), Dr. Smith speaks of the possibility