View report page

5
standard for comparison. It was first used by Mr. W. H. Power in 1876 in relation to the circumstances
of an outbreak of diphtheria at Brailes in Warwickshire. Mr. Power says in his report on this outbreak,
" I addressed my inquiry to the exact circumstances of the 25 families that were actually
invaded by the disease, and found that information of one sort was to be gained from the conditions of
the 25 first sufferers in their respective families, and information of another sort from the circumstances
of the 131 other persons who made up the 25 families." The method of comparison then instituted
has since been frequently made use of, and was notably employed in a report by Mr. Power on
diphtheria at Pirbright. The method of the report last referred to will be followed in discussing the
facts observed in connection with notified cases of diphtheria at Lewisham.
With the object of obtaining the necessary data, I'made, in the course of my inquiry in
Lewisham, a census of the persons living in invaded houses. Moreover, inquiry was made in all cases
as to the date of commencement of the illness of persons attacked by diphtheria.
On analysing, in the light of the information obtained, the notifications received from the affected
area it is found that between July 9th and October 19th individuals belonging to 60 households began
to suffer from diphtheria or from a throat illness which was followed by diphtheritic paralysis. In
these households 45 secondary cases of diphtheria were notified.
The 60 households included, apart from the original sufferers introducing diphtheria into each
house, a population of 43 babies from 0-3 years of age, 106 children, from 3-12 years of age, 29 persons
from 12-15 years of age, and 200 persons aged 15 years and upwards. The secondary cases included
11 babies, 26 children aged 3-12, 3 persons aged 12-15, and 5 persons aged 15 and upwards.
As regards the behaviour of diphtheria therefore in respect to persons of various ages in the
families that had become invaded, it appears that the percentage of attacks was for the four age periods in
question, 256 per cent., 24.5 per cent., 10.3 per cent., and 25 per cent. According to the standard thus
obtained babies aged 0-3, and children aged 3-12, are about equally affected, and the attack rate for these
age periods is about 2½ times that for the period 12-15, and 10 times that for the period 15 and upwards.
This standard may now be applied to the facts observed with regard to first sufferers in non-infected
houses. There were living in the affected area—
At ages 0-3 647, of whom 7 were first sufferers.
„ 3-12 1,726 „ 48
„ 12-15 487 „ 3
„ 15 and upwards 5,022 „ 2 „ „
These figures give attack rates of 11 per cent., 2'8 per cent., 0'62 per cent., and 0.04 per cent. In
other words, the actual circumstances with regard to houses newly invaded show that children 3-12
have suffered nearly 3 times as often as babies, 4½ times as often as children 12-15, and 70 times as
often as those 15 and upwards. These results may be compared with those of the standard results
thus—
Children 3-12 have been first sufferers nearly 3 times as often as babies 0-3, instead of as in
the standard results at about the same rate.
Children 3-12 have been first sufferers 4½ times as often as persons aged 12-15, instead of as
in the standard results at about 2½ times the rate.
Children 3-12 have been first sufferers 70 times as often as persons aged 15 and upwards,
instead of as in the standard results at about 10 times the rate.
The results obtained from the three methods of comparison above described are so striking as to
preclude any doubt as to their significance. The age period 3-12, and more particularly the age period
3-10, has clearly, in the Lewisham outbreak, suffered in a wholly exceptional manner.
An important fact now requires to be stated, and it is this : that of the 48 children at the
age period 3-12 who were the first sufferers in households, 42 had within a week of their showing
symptoms of illness been attending one or other of two schools. If consideration be limited to the
attacks occurring between September 1st and October 10th it will further be found that out of a total
of 48 first sufferers 43 were children aged 3-12, and of these 40 had been recently attending one or
other of the two schools. As regards the five cases not occurring in persons at the age periods 3-12,
one was a school attendant aged 13, and in two instances a school attendant belonging to the family in
which the case of diphtheria was notified had suffered from sore throat, prior to the development of the
illness which was declared to be diphtheritic in character.
The question as to the part played by " school influence " in promoting the spread of [disease
was thus seen to call for special study.
There are in the affected area three schools—
(a) The Lswisham-bridge Board school, having 1,254 children on the register and an
average attendance of 971 children (356 boys, 316 girls, and 299 infants) for the week ending
August 28th.
(b) The St. Stephen's National school, having 525 children on the register and an
average attendance of 408 children (190 boys, 112 girls, and 106 infants) for the week ending
August 28th.
(c) An industrial school having 150 boys aged from 5-13. These boys lived and were
educated in the school, and were not therefore in association with the general population.
It may be added that the numbers given for the National school include about one hundred boys
and infants belonging to an orphanage situated immediately outside the affected area.
It has been already stated that among notified cases of diphtheria 42 children, aged 3-12, first
sufferers in households, had been in recent attendance at one or other of these schools; it may now be
added that 33 of these attended the Board school and 9 the National school. If consideration be limited
to the attacks occurring between September 1st and October 10th, it will be found that out of a total of
43 first cases notified in households, among children aged 3-12, 31 cases were those of children
attending the Board school and 9 were cases of children attending the National school.