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Medical History, 2005, 49: 29–54
The Effects of the 1918–1919 Influenza Pandemic
on Infant and Child Health in Derbyshire
ALICE REID*
In early 1919 my father, not yet demobilized, came on one of his regular, probably irregular, furloughs
to Carisbrook Street to find both my mother and sister dead. The Spanish Influenza pandemic had
struck Harpurhey. There was no doubt of the existence of a God: only the supreme being could
contrive so brilliant an afterpiece to four years of unprecedented suffering and devastation. I
apparently, was chuckling in my cot while my mother and sister lay dead on a bed in the same room.
1
Towards the end of the First World War, the world was gripped by the ravages of a
pandemic of influenza. The disease spread rapidly across the globe with an alarming lack of
discrimination as to who it attacked and a tendency to pneumonic complications—causing
massive relative increases in mortality in young adults. In the 1920s it was estimated that,
between the spring of 1918 and the early summer of 1919, the disease had affected 200 to
700 million people and killed between 10 and 21 million.
2
In 1991 David Patterson and
Gerald Pyle increased the estimates to between 24.7 and 39.3 million, but Ian Mills uncov-
ered a death toll of over 21 million in India alone and more recent revisions have raised
probable global influenza mortality to between 50 and 100 million.
3
Even the conservative
estimates put the death toll from influenza at over twice that produced by the First World
War and it is generally accepted to be far higher. Yet while the war has been held responsible
for the creation of a ‘‘lost generation’’, the ’flu was rapidly relegated to obscurity. The
experience of the war and its consequences in terms of not only mortality but also social and
economic re-organization (and, in the UK at least, the arrival of the Armistice during
the most virulent period of the epidemic
4
) must have altered the public perspective and
diminished the memory of the influenza epidemic.
5
Although the widespread sickness
# Alice Reid 2005
*Alice Reid, PhD, Cambridge Group for the History
of Population and Social Structure, Department
of Geography, Sir William Hardy Building,
Cambridge CB2 3EN.
1
Anthony Burgess, Little Wilson and Big God:
being the first part of the confessions of Anthony
Burgess, London, Heinemann, 1987, p. 18. I would
like to thank Niall Johnson for drawing my attention
to this passage.
2
Geddes Smith, Plague on us, London, Oxford
University Press, 1941; Fred R van Hartesveldt (ed.),
The 1918–1919 pandemic of influenza: the urban
impact in the western world, Lampeter, Edwin Mellen
Press, 1992, p. 1.
3
David K Patterson and Gerald F Pyle, ‘The
geography and mortality of the 1918 influenza
pandemic’, Bull. Hist. Med., 1991, 65: 4–21, p. 19;
I D Mills, ‘1918–1919 influenza pandemic: the Indian
experience’, Ind. Econ. soc. Hist. Rev., 1986, 23: 1–40;
Niall Johnson, ‘Aspects of the historical geography
of the 1918–19 influenza pandemic in Britain’, PhD
thesis, University of Cambridge, 2001, p. 158; Niall
P A S Johnson and Juergen Mueller, ‘Updating the
accounts: global mortality of the 1918–1920
‘‘Spanish Influenza’’ pandemic’, Bull. Hist. Med.,
2002, 76: 105–15.
4
In many countries the peak had already past by
the time of the Armistice and general demobilization,
but Crosby describes recrudescences of the epidemic
associated with Armistice celebrations in the United
States. Alfred W Crosby, America’s forgotten
pandemic: the influenza of 1918, Cambridge University
Press, 1989, pp. 85, 105. See also Johnson, op. cit.,
note 3 above, p. 183.
5
The public perception of a full scale epidemic may
have been tempered by the muted press reports in
combatant nations where the full extent of the death toll
29
undoubtedly placed additional strains on society and the economy, these appear to a large
extent to have been subsumed into the experience of the war itself.
6
Research on the influenza pandemic, after a largely dormant period, has enjoyed a recent
boom. This has resulted in improved estimates of mortality and morbidity, and descriptions
of the course of the epidemic and patterns of response in different places.
7
These newer
studies have focused on the disproportionate adult mortality which was so alarming for
those who lived through it, further depleting those generations most affected by the war and
heightening social and economic dislocation. The completely abnormal vulnerability of
those in the prime of their lives made a stark contrast to the usual age pattern of influenza
mortality, which was higher among the youngest and oldest age groups. The experience of
Anthony Burgess, described above, reflects this unusual age pattern. Anthony’s mother, a
young healthy woman, and his older sister of four years died, while he, not much more than a
year, was spared. In fact, although those in their twenties and thirties did experience the
largest proportionate increases from the very low normal mortality of those age groups,
absolute numbers of deaths to infants and children under the age of five were still sub-
stantial, and relative increases in this age group were smaller only because initial levels were
higher.
8
Christopher Langford has suggested that the unusual age pattern of the 1918–19
pandemic was due to immunity conferred by previous epidemics among the elderly, and that
mortality among the younger age groups was not abnormally low.
9
Infants and young
children are a particularly vulnerable group in any circumstances, and only the year before
the pandemic nearly 10 per cent of infants born in England and Wales died before their first
birthday. Children whose mothers have died are at particularly high risk,
10
and it may
therefore be more pertinent to ask, not why Anthony’s mother died, but why Anthony
himself did not.
While young adults undoubtedly did suffer proportionately more than other age groups,
this does not mean that others, particularly the very young, were spared. It has been
concluded that the ‘‘impact of the First World War on British society was inextricable
from the influenza epidemic’’,
11
but because the very young were not embroiled in the war
to the same extent as adults (although the possible effects of war on infant and child health
was not reported. In neutral Spain, the pandemic
received far greater prominence in the press, and it was
reports in the London press of epidemic influenza in
Spain which led to it being called ‘‘the Spanish ’flu’’.
Patterson and Pyle, op. cit., note 3 above, p. 7; Johnson,
op. cit., note 3 above, pp. 105–9.
6
Sandra M Tomkins, ‘Britain and the influenza
pandemic of 1918–19’, PhD thesis, University of
Cambridge, 1989, ch. 3.
7
See Johnson, op. cit., note 3 above; Christopher
Langford, ‘The age pattern of mortality in the 1918–19
influenza pandemic: an attempted explanation based on
data for England and Wales’, Med. Hist., 2002, 46:
1–20; Johnson and Mueller, op. cit., note 3 above;
J S Oxford, A Sefton, R Jackson, N P A S Johnson
and R S Daniels, ‘Who’s that lady?’, Nature Medicine,
1999, 5(12): 1351–52; Svenn-Erik Mamelund,
‘Spanish influenza mortality of ethnic minorities
in Norway 1918–1919’, Eur. J. Popul., 2003,
19: 83–102.
8
Langford, op. cit., note 7 above, p. 11. See also G
Cerasoli, ‘Italian pediatricians and the influenza
pandemic of 1918–19’, Ital. J. Pediatr., 2002, 28:
163–6, p. 164.
9
Langford, op. cit., note 7 above, pp. 11, 15–16.
10
Irvine Loudon, Death in childbirth: an
international study of maternal care and maternal
mortality 1800–1950, Oxford, Clarendon Press, 1992,
p. 484, quotes studies showing mortality among infants
whose mothers died within one year after the
confinement to be four to five and a half times higher
than among infants whose mothers did not die.
11
Sandra M Tomkins, ‘The failure of expertise:
public health policy in Britain during the 1918–19
influenza epidemic’, Soc. Hist. Med., 1992, 5(3):
435–54, p. 453.
30
Alice Reid
must not be forgotten
12
), examination of infants and children may offer the potential for
separating the effects of the pandemic from those of the war. This is not meant to imply that
the effect of the influenza pandemic on infants and young children can be extrapolated to
adults; indeed, this paper demonstrates that there can be a variety of different mechanisms
by which influenza can affect health in infancy and childhood. Nor is it intended to suggest
that the pandemic cannot be looked at by examining its effect on women, as has been ably
done already. This study merely seeks to present another perspective on the pandemic, and
therefore aims to isolate the effects of the 1918–19 influenza epidemic from other influences
on infant and child health in Derbyshire. The analysis uses an individual level data set of
30,488 infants born between January 1917 and December 1922 to look at mortality rates by
cause, while controlling for other influences. It identifies those infants most at risk during
the epidemic and judges the direct, indirect and associated effects of the influenza epidemic
on infant and child health and survival.
The Influenza Pandemic in England and Wales
Although contemporary reports attributed the origin of the influenza pandemic to Spain
in 1918, hence the name ‘‘the Spanish ’flu’’, it now seems more likely that the virus
responsible originated as early as 1915, and that isolated outbreaks of the disease labelled
purulent bronchitis were occurring in England and France in 1916 and 1917.
13
However, the
pandemic did not start in earnest until 1918, with the first of three waves. This ‘‘spring’’
wave hit the United States in March 1918 and Europe in May and June. By July and August it
was waning, but was rapidly superseded by the ‘‘autumn’’ wave, a much more lethal strain
starting in France in August and spreading throughout Europe and further afield during
September and October. A final wave followed in the early months of 1919. The first wave
in Britain was relatively mild, although the North and the North Midlands witnessed a
sudden change in late June when the number of deaths to young adults increased. World-
wide the second wave was the most virulent, and this was also true for the southern parts of
Britain. In the North and the North Midlands the second wave was less dramatic, but
sustained, and these regions suffered more than other areas in the third wave.
The estimation of mortality and morbidity rates due to the pandemic is fraught with
difficulty, partly connected with the war. With many men serving in the army, mostly
overseas, population denominators (the numbers of people at risk) are difficult to determine.
Therefore, while there were numerically more deaths among the female civilian population,
the Registrar-General estimated the death rate among the civilian male population to have
been higher.
14
Assessment is also complicated by the fact that although many deaths were
recorded as a direct result of influenza, the disease would also have contributed, directly or
12
In Britain, available evidence suggests that
regular wages and food supplements may have
improved infant health during the war
(J M Winter, ‘The impact of the first world war
on civilian health in Britain’, Econ. Hist. Rev.,
1977, 30: 487–507; idem, ‘Aspects of the impact
of the first world war on infant mortality in
Britain’, J. Eur. Econ. Hist., 1982, 11:
713–38).
13
These outbreaks shared the same precise clinical
and physiological descriptions as the influenza of the
pandemic. Oxford, et al., op. cit., note 7 above. See also
Johnson, op. cit., note 3 above, pp. 113–21.
14
Registrar-General, Supplement to the eighty-first
annual report of the Registrar-General, Report on
the mortality from influenza in England and Wales
during the epidemic of 1918–19, London, HMSO,
1920, p. 5.
31
1918–1919 Influenza Pandemic and Child Health
indirectly, to deaths attributed to other conditions. For example, deaths from pneumonic
complications—a direct result of influenza—were often recorded simply as pneumonia.
Influenza would also have been a key factor in deaths from other causes among people who
might not have died were it not for the presence of the influenza virus. Diagnoses were often
confused and record keeping was inadequate
15
: influenza was not made a notifiable disease
until the final stages of the epidemic. Given the similarity of recorded cases of purulent
bronchitis, it is also possible that influenza was under-recorded in the early stages of the
pandemic and perhaps overstated later.
16
The recording problems associated with the war mean that many of the official estimates
of mortality concentrate on women, and the other problems with recording suggest that it
may be most instructive to examine overall, rather than cause-specific, death rates (which
sometimes include associated causes and sometimes do not). Until the last quarter, 1918 was
a very healthy year for England and Wales, but that was changed completely by the second
wave of the epidemic, making 1918 the first year in which deaths (to civilians) outstripped
births since records began. It has been estimated that between 30 and 75 per cent of the
population was affected by influenza, that around 20 per cent of cases suffered complica-
tions, of which 40 per cent died.
17
The Registrar-General officially attributed 200,000
deaths to the disease.
18
Figure 1 shows that during the fourth quarter of 1918 when the
epidemic was at its most deadly, mortality to women aged 25 to 30 was nearly 600 times
higher than it had been for the average of the same quarters of the previous four years.
‘‘Woe unto Them that are with Child’’:
19
Influenza and Pregnancy
Figure 1 demonstrates clearly the peculiar phenomenon during the ‘‘Spanish ’flu’’ of
highest proportionate increases in mortality among young adults, particularly those in their
twenties and thirties. For women, these are the child-bearing years, and pregnant women
were at particularly high risk of becoming infected. The mortality of all women aged
between 15 and 49 due to influenza during the epidemic was 4.9 per thousand, but that
of pregnant women was between 5.3 and 5.7 per thousand.
20
This statistic is elucidated by
studies performed in the USA, where it was found that, compared to women not recorded as
pregnant, expectant women had a 50 per cent higher chance of developing pneumonic
complications. Once complications had developed, such women were 50 per cent more
likely to die.
21
Studies of the two subsequent epidemics and of non-epidemic seasons have
shown that pregnant women are at particularly high risk from influenza towards the end of
their pregnancy. In the ‘‘Asian ’flu’’ pandemic of 1957 half of all influenza-related deaths
15
Fred R van Hartesveldt, ‘Manchester’, in van
Hartesveldt (ed.), op. cit., note 2 above, pp. 91–103, on
p. 91.
16
Oxford, et al., op. cit., note 7 above, p. 1351.
17
Tomkins, op. cit., note 6 above, pp. 26, 30.
18
Registrar-General, op. cit., note 14 above, p. 7.
19
Lancet, 18 Oct. 1919, ii, p. 699, quoted in
Johnson, op. cit., note 3 above, p. 265.
20
A W Bourne, ‘Influenza: pregnancy, labour, the
puerperium, and diseases of women’, in F G
Crookshank (ed.), Influenza: essays by several authors,
London, Heinemann, 1922, pp. 433–43, on pp. 439–40.
This difference is probably understated as pregnancy
was not always noted on the death certificate and
it is probable that many of the other women in the
child-bearing ages who died were also pregnant.
21
John W Harris, ‘Influenza occurring in pregnant
women, a statistical study of thirteen hundred
and fifty cases’, J. Am. med. Assoc., 1919, 72
(3 April): 978–80, p. 798. See also Paul A Buelow,
‘Chicago’, in van Hartesveldt, op. cit., note 2 above,
119–45, on p. 131, who states that 46 per cent of all
32
Alice Reid
among women of childbearing age occurred in those who were pregnant.
22
Furthermore, a
recent study of non-epidemic risk demonstrated that being in a late stage of pregnancy was
an independent risk factor for hospitalization for influenza, pneumonia, and a broader range
of acute cardiopulmonary conditions, although actual mortality was rare. Women in their
second trimester of pregnancy had an influenza-attributable risk five times that of post-
partum women, a factor which rose to nine for those in their third trimester.
23
This suscept-
ibility of pregnant women may be due to changes in blood circulation,
24
reduced functional
capacity of the lungs,
25
or to the immunosuppression necessary to prevent rejection of the
foetus (sometimes referred to as ‘‘pregnancy associated immunodeficiency syndrome’’
(PAIDS)) which also leaves women more vulnerable to infection.
26
hospitalized pregnant women died from ’flu and
pneumonia in Chicago.
22
See Sir Charles H Stuart-Harris, Geoffrey C
Schild and John S Oxford, Influenza: the viruses and the
disease, 2nd ed., London, Edward Arnold, 1985, p. 105;
Edwin D Kilbourne, Influenza, New York, Plenum
Medical, 1987, p. 163.
23
Kathleen Maletic Neuzil, George W Reed,
Edward F Mitchel, Lone Simonsen and Marie R Griffin,
‘Impact of influenza on acute cardiopulmonary
hospitalizations in pregnant women’, Am. J.
Epidemiol., 1998, 148: 1094–102.
24
Kilbourne, op. cit., note 22 above, p. 163.
25
Neuzil, et al., op. cit., note 23 above, p. 1101.
26
E Weinberg, ‘Pregnancy and resistance to
infectious disease’, Rev. Infect. Dis., 1984, 6: 814–31.
Not to be confused with PAIDS referring to paediatric
acquired immunodeficiency syndrome (see Arthur A
Ammann, Diane W Wara and Mort J Cowan,
‘Pediatric acquired immunodeficiency syndrome’,
Ann. N. Y. Acad. Sci., 1984, 437: 340–9).
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85
a
g
e
g
roup
0
100
200
300
400
500
600
factor increase
Figure 1: Factor increase infemalemortality during the ’flu epidemic, fourthquarter of1918 compared
to average of fourth quarters 1914–17. (Source: Registrar-General, Supplement to the eighty-first
annual report of the Registrar-General, Report on the mortality from influenza in England and Wales
during the epidemic of 1918–19, London, HMSO, 1920, p. 8.)
33
1918–1919 Influenza Pandemic and Child Health
The well-established increased risk to pregnant women is likely to have been heightened
during 1918–19 due to the unusual age structure of influenza in this particular epidemic, and
there is evidence that influenza infection may also have precipitated foetal loss. In England
and Wales the death rate from spontaneous abortion in 1917 was 0.16 per thousand (one in
6,302 pregnancies), whereas during the epidemic the death rate from only those miscar-
riages linked to influenza was ten times greater at 1.60 per thousand (one in 624 pregnan-
cies).
27
If influenza could provoke this level of increase in such deaths, it is likely that it was
responsible for a great many more non-fatal spontaneous abortions. In the USA, pregnancy
was interrupted in 26 per cent of uncomplicated cases of influenza and in 52 per cent of cases
complicated by pneumonia.
28
Foetal loss and premature delivery may also have generated a
higher number of stillbirths and premature live infants during or shortly after the pandemic.
This is corroborated by evidence that higher rates of early neonatal mortality after four of the
five influenza epidemics between 1948 and 1971 were due to an increase in the prematurity
rate, probably as a result of infection to mothers in the first or second trimesters.
29
However
there has been little other evidence to support the effect of influenza on the premature
termination of pregnancy or stillbirth.
30
A similar uncertainty hangs over the effect of maternal influenza during pregnancy on the
risk of birth defects. Although there is some evidence for exposure during the first trimester
increasing the occurrence of central nervous system defects (particularly anencephaly),
circulatory malfunctions, cleft palate and reduction deformities,
31
there is also evidence
against such associations. J S McKenzie and M Houghton, in their review of the literature,
conclude that no direct association between influenza infection during pregnancy and
congenital malformations can be substantiated, except for cleft lip and reduction defor-
mities for which the effect is small.
32
They do not rule out an indirect association, however.
The ‘‘Spanish ’flu’’ therefore hit pregnant women hard, with the consequent effects of
increased stillbirths and possibly also more prematurity, which would produce more infants
subject to the high risks of all pre-term or small infants. Maternal influenza may also have
affected the health of infants and children by its repercussions on the quality of care a mother
was able to give her child. Infants whose mothers die are generally at greater risk of death,
partly through the cessation of breast-feeding. A severe, but non-fatal, illness in the mother
could curtail her ability to breast-feed, thus also increasing the risks for the infant. Figure 1
shows that although the proportionate increase in mortality was not as high as in adulthood,
deaths among infants and young children did increase by a factor of between 150 and 300
during the ‘‘Spanish ’flu’’ of 1918–19. Many such young people may have died directly
from influenza itself, but this paper attempts to evaluate the different ways in which a
mother’s illness or death might have affected her child’s chances of survival, and compares
them with the direct effects of the influenza virus on infants and children.
27
Bourne, op. cit., note 20 above, p. 437.
28
Harris, op. cit., note 21 above, p. 979. See also
Johnson, op. cit., note 3 above, p. 265, for similar
statistics for Paris and Sydney.
29
G Wynne Griffith, A M Adelstein, P M Lambert,
J A C Weatherall, ‘Influenza and infant mortality’,
Br. med. J., 1972, iii: 553–6.
30
See J S MacKenzie and M Houghton, ‘Influenza
infections during pregnancy: association with
congenital malformations and with subsequent
neoplasms in children, and potential hazards of live
virus vaccines’, Bacteriol. Rev., 1974, 38: 356–70.
31
Victoria P Coffey and W T E Jessop, ‘Maternal
influenza and congenital deformities: a prospective
study’, Lancet, 1959, ii: 935–7.
32
MacKenzie and Houghton, op. cit., note 30
above, p. 364.
34
Alice Reid
The Data Source
Data sources which might enable these issues to be addressed are rare for England and
Wales, but this paper uses a set of notification of births registers drawn up to enable health
visitors to visit infants soon after birth and periodically thereafter until a maximum age of
five years. The ledgers include both live and still births and also record information about
the socio-economic situation of the household (parents’ occupations, the number of rooms
in the house) and demographic information such as multiple birth, parity, and so on. Notes
made by the health visitors during their visits relating to the method of feeding the child, its
health and development were also transcribed. The records include all 30,488 births occur-
ring in the rural and small town areas of western and southern Derbyshire between January
1917 and December 1922. The data set yields high quality individual level longitudinal data
which is ideal for the purpose of this paper.
33
Influenza in Derbyshire
Although this paper will concentrate on the effects of influenza on the very young, it is
instructive to put this into context by describing the influenza epidemic in Derbyshire
generally. Figure 2 shows the amalgamated numbers of deaths from influenza in the county
and municipal boroughs for which numbers were recorded separately,
34
and of those in the
remaining towns and rural areas of Derbyshire.
35
In common with many urban areas,
Derbyshire towns witnessed slightly earlier mortality peaks in each wave of the epidemic
than the rural areas, a characteristic which Niall Johnson has suggested is linked to the
spread of the virus along routes of communication and diffusion out into more sparsely
populated districts. He also suggested that northern regions suffered more than southern.
36
Having a greater total population, numbers of deaths were higher in the ‘‘rest of Derbyshire’’
than in the towns, but the chance of death was not appreciably different, as indicated by the
death rates shown in bold in Figure 3. This Figure also shows weekly death rates for London,
for cities and large towns in the North Midlands (apart from Derbyshire, which would
normally be classed as part of that region), the West Midlands, and all England and Wales,
and for all other areas in the North Midlands (not including Derbyshire), the West Midlands
and all England and Wales, which allow Derbyshire’s experience of the influenza pandemic
to be compared to other places in England and Wales.
37
The diagram shows that influenza
33
The birth registers are temporarily housed in the
Cambridge Group for the History of Population and
Social Structure, on loan from the MRC Unit in
Southampton. The data set is described in more detail
elsewhere. See Alice Reid, ‘Infant and child health and
mortality in Derbyshire from the Great War to the mid-
1920s’, PhD thesis, University of Cambridge, 1999;
idem, ‘Neonatal mortality and stillbirths in early
twentieth century Derbyshire, England’, Popul. Stud.,
2001, 55(3): 213–32; idem, ‘Infant feeding and post
neonatal mortality in Derbyshire, England, in the early
twentieth century’, Popul. Stud., 2002, 56(2):151–66.
34
These were Derby CB, Chesterfield MB, Glossop
MB, and Ilkeston MB. None of these towns, nor Buxton
MB, contributed to the data set.
35
The data on which this graph was based were
kindly provided by Niall Johnson.
36
See Johnson, op. cit., note 3, pp. 320–6.
37
The rest of the North Midlands includes
Lincolnshire, Nottinghamshire, Rutland, and
Leicestershire (and it would normally include
Derbyshire, which is here shown separately). The West
Midlands consists of Gloucestershire, Herefordshire,
Worcestershire, Warwickshire, Shropshire, and
Staffordshire. Cities and large towns include county
boroughs, London boroughs, and metropolitan
boroughs and large urban areas with populations
greater than 20,000. These data are derived from the
data set SN4350 ‘1918–1919 influenza pandemic
mortality in England and Wales’ in the UK data archive,
35
1918–1919 Influenza Pandemic and Child Health
mortality in the second wave hit London earlier than combined figures for the Midlands and
other parts of the country. The epidemic travelled northwards, through the West Midlands,
Derbyshire, and the rest of the North Midlands, climaxing in the urban areas of each district
before the less densely populated places, and getting progressively more lethal as it
travelled.
Weekly data as shown in Figures 2 and 3 are of great value in distinguishing different
patterns in an epidemic with relatively short-lived periods of intense activity, and use of
such data is possible where there are large numbers of events. With smaller groups, such as
will be examined below, the fluctuations in weekly deaths or death rates produced by small
numbers mean that it is easier to compare monthly data. As a comparison with what follows,
the monthly influenza mortality rates for the large urban areas and the ‘‘rest of Derbyshire’’
29/06/18
13/07/18
27/07/18
10/08/18
24/08/18
07/09/18
21/09/18
05/10/18
19/10/18
02/11/18
16/11/18
30/11/18
14/12/18
28/12/18
11/01/19
25/01/19
08/02/19
22/02/19
08/03/19
22/03/19
05/04/19
19/04/19
03/05/19
week endin
g
0
50
100
150
200
250
numbers of deaths
rest of Derbyshire
Large towns (Derby, Chesterfield, Glossop, Ilkeston)
Figure 2: Weekly numbers of deaths from influenza in Derbyshire from the week ending 29 June 1918
until the week ending 3 May 1919. (Source: Registrar-General, Supplement to the eighty-first annual
report of the Registrar-General, Report on the mortality from influenza in England and Wales during
the epidemic of 1918–19, London, HMSO, 1920. Figures provided by Niall Johnson.)
created by Niall Johnson. The original published source
was the Registrar-General, op. cit., note 14 above,
pp. 48–80.
36
Alice Reid
are shown in Figure 4, and demonstrate that the more subtle differences in timing visible
with weekly figures are lost by monthly data.
The health visitor data set used to examine the effect on infants and children relates to a
sub-set of the ‘‘rest of Derbyshire’’,
38
and annual influenza deaths by administrative unit
given in the Registrar-General’s annual reports show that the area covered by the data set
contributed 52 per cent of all influenza deaths occurring in the wider area in 1918 and 1919.
The same source demonstrates that 3.67 per cent of influenza deaths in Derbyshire were of
29/06/18
13/07/18
27/07/18
10/08/18
24/08/18
07/09/18
21/09/18
05/10/18
19/10/18
02/11/18
16/11/18
30/11/18
14/12/18
28/12/18
11/01/19
25/01/19
08/02/19
22/02/19
08/03/19
22/03/19
05/04/19
19/04/19
03/05/19
week endin
g
0
10
20
30
40
death rates per 1,000 population
Rest of Derbyshire
Large towns (Derby, Chesterfield, Glossop, Ilkeston)
London
England and Wales: towns
England and Wales: rest
North Midlands: towns
North Midlands: rest
West Midlands: towns
West Midlands: rest
Figure 3: Weekly death rates from influenza in Derbyshire and other areas from the week ending 29
June 1918 until the week ending 3 May 1919. (Source: These data are derived from the data set SN4350
‘1918–1919 influenza pandemic mortality in England and Wales’ in the UK data archive, created by
Niall Johnson. The original published source was the Registrar General, Supplement to the eighty-first
annual report of the Registrar-General, Report on the mortality from influenza in England and Wales
during the epidemic of 1918–19, London, HMSO, 1920, pp. 48–80.)
38
The data set excludes the County Borough of
Derby, the Municipal Boroughs of Ilkeston,
Glossop, Buxton, and Chesterfield, and the rural and
small town area around Chesterfield, as these were
administered separately.
37
1918–1919 Influenza Pandemic and Child Health
infants under the age of one, and on the basis of this, and a small adjustment for the fact that
the areas covered by the data set had lower mortality than the rest of Derbyshire, we could
expect 32 infant deaths attributed to influenza in the data set, as set out in Table 1. In fact the
data set records 23 deaths, fewer than expected because some infants had already ceased to
be visited by the time they were one year old, and deaths of infants no longer visited were not
recorded in the data set. Similarly, as also shown in Table 1, the published figures could lead
us to expect 37 influenza deaths between the ages of one and two. In fact we see only six as,
again, some deaths would have been of children who were no longer being seen by health
visitors and some deaths of one-year-olds in 1918 would have been of children born in late
1916 and not yet turned two. We cannot examine influenza deaths at older ages of childhood
as none of the children covered by the data set were more than two years old during the worst
part of the epidemic. However, we may observe some maternal mortality: on the basis of the
published county figures, there were probably around 158 deaths of women aged between
25 and 45, the prime childbearing period, in the area covered by the data set. Only a small
percentage of these were likely to have been mothers of children under the age of two,
however. As shown in Table 1, on the basis of national fertility rates, between 15 and 20 per
cent of women aged 25 to 45 had children under the age of two, therefore we might expect
June 1917
July 1918
August 1918
September 1918
October 1918
Nove
mber 1918
December 1918
Janu
ary
1919
February 1919
M
arch 1919
April
1919
May 1919
0
5
10
15
20
25
death rates per 1,000 population
Rest of Derbyshire
Large towns (Derby, Chesterfield, Glossop, Ilkeston)
Figure 4: Monthly death rates from influenza in Derbyshire during the 1918–19 epidemic. (Source:
Registrar-General, Supplement to the eighty-first annual report of the Registrar-General, Report on the
mortality from influenza in England and Wales during the epidemic of 1918–19, London, HMSO, 1920.
Derived from figures provided by Niall Johnson.)
38
Alice Reid
Table 1
Influenza deaths in Derbyshire 1918–19: calculation of deaths expected in the health
visitor data set
Infants Age 1 to 2
Women
age 25–45
A Influenza deaths in Derbyshire (incl. Derby) 2993 110 127 545
B Influenza deaths to age group as a proportion
of all influenza deaths in the county
(calculated from A)
0.036 0.042 0.182
C Number of influenza deaths in the
area covered by the health visitor data set
1036
D Estimated numbers of influenza
deaths in the area covered by the
data set on the basis of the proportions in B
38 44 189
E Adjustment for lower mortality in
the area covered by the data set (*0.839)
32 37 158
F Estimated births per year to women aged
25–49
8494
G Estimated proportion of women aged 25–45
with a child less than two years old, assuming
each woman had only one child in the
time period.
0.201
H Estimated proportion of women aged
25–45 with a child less than two
years old, assuming half of those women
had two children in the two years.
0.150
I Estimated deaths of women in the data set
(i.e. mothers of children under the age
of two), based on G
32
J Estimated deaths of women in the data
set (i.e. mothers of children under the
age of two), based on H
24
Sources:
A, C: Eighty-first annual report of the Registrar-General of births, deaths, and marriages in
England and Wales (1918), Cmd. 608 1920, pp. 245, 282 and 346–8. Eighty-second annual report
of the Registrar-General of births, deaths, and marriages in England and Wales (1919), Cmd. 1017
1920, pp. 315, 352 and 416–18.
E: based on ratio of the infant mortality rate in the area covered by the data set (70.59) to that in
all Derbyshire (84.13), calculated from Registrar-General’s annual reports. See Alice Reid,
‘Neonatal mortality and stillbirths in early twentieth century Derbyshire, England’, Popul. Stud.,
2001, 55 (3): 213–32, p. 215, Table 1.
F: calculated from age-specific marital fertility rates for England and Wales for 1922 (Robert
Woods, The demography of Victorian England and Wales, Cambridge University Press, 2000, p. 130),
and the numbers of married women in Derbyshire in each 5-year age group in 1921, as given in the
Census of England and Wales 1921: County of Derby, 1923, London, HMSO, Table 14, p. 39.
G: based on two years of births to women in the age group, divided by the number of all women
in the age group.
39
1918–1919 Influenza Pandemic and Child Health
between 24 and 32 deaths of mothers in our data set. In fact we see 16 deaths of mothers
during the epidemic year directly attributed to the ’flu, and a further 30 with insufficient
causal information, but in which ’flu might have been implicated.
It is clear that the data set records fewer deaths from influenza than actually occurred in
the area covered, and it can be shown that a similar error appears with mortality from any
cause. The shortfall is due to the fact that health visitors stopped visiting some infants, and
the deaths of these infants are not recorded. Fortunately this can be taken account of using
life table techniques and hazard modelling,
39
which calculate a series of rates using those
known to be in observation at each unit of time, and which produce overall infant mortality
rates and early childhood (1–5 years) mortality rates not significantly different to those
calculated from vital registration. The infant mortality from the data set is 68.70 infant
deaths per thousand births, and that calculated from vital registration is 70.59; the corre-
sponding figures for the early childhood mortality rate are 29.0 and 29.7 deaths per thousand
children in the age group.
40
There is no reason to suppose that influenza deaths were any less
accurately recorded than other infant deaths. In fact, given the difficulty of accurately
ascribing causes to many infant deaths,
41
those from influenza might have been more easily
recognized, and thus more correctly recorded than others, consequently the data set can be
relied upon to produce a reasonably exact reflection of the risks of dying from influenza
mortality during the epidemic.
The Effects of the Influenza Epidemic on Infant and Child Mortality
Figure 5 shows indexed monthly post-neonatal mortality rates for the influenza epidemic
in comparison with the other years in the data set. The x-axis shows the year running from
July 1918 to June 1919, to capture the entire epidemic year. The graph shows that the second
wave, peaking in Derbyshire in November 1918, raised post-neonatal mortality well above
its normal seasonal winter peak. Figure 6 shows that mortality for the second year of life was
strongly affected in the first and third waves as well as the second, the third wave peaking
slightly earlier than for all age groups. In contrast neonatal mortality and the stillbirth rate
(Figures 7 and 8) show different patterns. Neonatal mortality appears to have peaked in the
third wave: mortality rates were highest in February but also high in April and June. This
three-pronged pattern might suggest a lagged effect of the three waves (although the lag is
not the same in each case), which would be consistent with the hypothesis that influenza in
the first or second trimester of pregnancy increased prematurity rates and consequently
neonatal mortality.
42
The effect on stillbirths appears to have been concentrated in the
second wave with its prolonged high rates. As with neonatal mortality, however, the
September peak could represent the delayed first wave, but with a shorter lag, and
the question then arises of why the second wave appears to have had an immediate effect.
39
For more information on life table techniques and
hazard modelling, see David W Hosmer and Stanley
Lemenshow, Applied survival analysis: regression
modeling of time to event data, New York and
Chichester, John Wiley, 1999.
40
Reid, ‘Infant and child health’, op. cit., note 33
above, p. 215. For the 1–5 figure, a life table measure
was generated by the data set and subsequently
transformed into an age-specific death rate.
41
Naomi Williams, ‘The reporting and
classification of causes of death in mid-nineteenth-
century England: the example of Sheffield’, Hist.
Methods, 1996, 29(2): 58–71.
42
Wynne Griffith, op. cit., note 29 above.
40
Alice Reid
Figures 7 and 8 are drawn to the same scale as Figures 5 and 6, revealing that although in
some months the risks of neonatal mortality and stillbirth were around twice as high for the
same months in other years, the increases in the risks of death before one month of age were
not as great as those for post-neonatal and early child mortality.
Period death rates identify the time periods at which more deaths occurred, but the
comparison of different influences on health and survival needs the identification of chil-
dren at risk of dying during the epidemic. In other words, it is necessary to isolate a cohort of
those who were born in a given time and were therefore in a particular age group during the
epidemic. Children at highest risk of stillbirth can be identified simply by their dates of birth:
those born between September 1918 and January 1919 were at highest risk and period and
cohort rates are identical. It is also easy to identify those at risk of neonatal mortality during
the epidemic by date of birth, because as the neonatal period is relatively short, most infants
spent all of it or none of it during the epidemic. Also, because the period of risk is just one
month following the birth, the cohort death rates for neonatal mortality in Figure 9 show a
similar pattern to Figure 7 (although different enough to detect a clearer three month lag
from the first and second waves of the epidemic to peaks in October and February). Those
born between January and April 1919 are identified as those at greatest risk of neonatal
mortality during the epidemic.
It is more difficult to identify those at risk of post-neonatal mortality because infants are at
risk for a much longer time. For example, children born in early 1918 would have been in
July
Au
g
ust
September
October
November
December
January
Februar
y
March
A
p
ril
May
June
0
100
200
300
percentage increase over monthly post neonatal mortality
peak of 1st wave for mortality at all ages
peak of 2nd wave for mortality at all ages
peak of 3rd wave for mortality at all ages
Figure 5: Indexed post-neonatal period monthly death rates in Derbyshire, late 1918 and early 1919
(monthly averages for other years 1917–22 ¼ 100). (Source: Derbyshire health visitor data.)
41
1918–1919 Influenza Pandemic and Child Health
peril from this form of death towards the end of their first year, at the beginning of the
epidemic. Children born at the end of 1918 would have been at risk only during their early
post-neonatal period, and at the end of the epidemic. Children born in the spring and early
summer of 1918 would have been exposed to the entire epidemic during their post-neonatal
period. Figure 10 shows monthly post-neonatal mortality rates, distinguishing those born in
each month of 1918 from those born in the corresponding month of other years, and
demonstrates that, unsurprisingly, all infants born in 1918 were at elevated risk from
the epidemic, as they all spent at least part of their post-neonatal lives exposed to the
influenza virus. Those born during the summer of 1918 (particularly between July and
September) had a much higher risk of dying. Such infants were in their early post-neonatal
period at the peak of the second, most virulent wave, and were still in this age group during
the third wave. Those born in February 1918, spending the first two waves in this age group
had the greatest excess risk, and it is unclear why those infants born in March and April
1918, who were exposed to all three waves, did not suffer as much. The problem of
identification is more acute for early child mortality and has not been attempted.
Once the cohorts at most risk have been identified, it is possible to quantify and compare
the result of exposure to the epidemic of a child born at a particular date with other
influences such as multiple birth, legitimacy, parental occupation, number of rooms in
the house, urban/rural residence and so on. Such a comparison can be made by using
July
Au
g
ust
September
October
November
December
January
Februar
y
March
A
p
ril
May
June
0
100
200
300
percentage increase over monthly mortality age 1-2
peak of 1st wave for mortality at all ages
peak of 2nd wave for mortality at all ages
peak of 3rd wave for mortality at all ages
Figure 6: Indexed early childhood period monthly death rates in Derbyshire, late 1918 and early 1919
(monthly averages for other years 1917–22 ¼ 100). (Source: Derbyshire health visitor data.)
42
Alice Reid
multivariate hazard analysis (for post-neonatal and neonatal mortality) and logistic analysis
(for the risk of stillbirth) and the following analyses show the risks of babies being stillborn,
of dying in the neonatal period, and of dying in the post-neonatal period associated with
birth during the influenza epidemic, while controlling for the effect of other influences on
the risk of mortality.
43
In the tables each odds ratio is derived from a different analysis, either
examining risk of different forms of death (i.e. stillbirth, neonatal mortality, or post-
neonatal mortality), or assessing the risks associated with being born at a different time
period. The odds ratios show the multiplicative increase in the risk of death for infants
born during particular time periods and thus at risk during the influenza epidemic. Thus
Table 2 shows that infants born at any time in the second or third waves of the epidemic (July
July
Au
g
ust
September
October
November
December
January
Februar
y
March
April
May
June
0
100
200
300
percentage increase over monthly neonatal death rates
peak of 3rd wave for mortality at all ages
peak of 2nd wave for mortality at all ages
peak of 1st wave for mortality at all ages
Figure 7: Indexed neonatal period monthly death rates in Derbyshire, late 1918 and early 1919
(monthly averages for other years 1917–22 ¼ 100). (Source: Derbyshire health visitor data.)
43
Independent variables significantly increasing
the risk of stillbirth were multiple birth, male sex, parity
one then increasing linearly with parity after parity two,
having a doctor present at the birth (as opposed to just a
midwife), father being manual social class, mother
having been employed during pregnancy, and being
born in winter months (October to April). Those
significantly increasing the risk of neonatal mortality
were multiple birth, male sex, parities four and above,
having a doctor present at birth, being born in winter
months, living in a more densely populated district, and
living in a district where over half the population had a
privy midden as opposed to more sanitary toilet facility
(see Reid, ‘Neonatal mortality’, op. cit., note 33 above,
pp. 216–21). Independent variables significantly
increasing the risk of post-neonatal mortality were
multiple birth, male sex, illegitimacy, higher parities,
having been artificially fed by the end of the first
month, living in a mining district, having fewer than
four rooms in the house, and living at higher
altitude (see Reid, ‘Infant feeding’, op. cit., note 33
above, pp. 155–7).
43
1918–1919 Influenza Pandemic and Child Health
1918 to April 1919) were 1.247 times (or 25 per cent) more likely to be stillborn than
infants born at another time in the 1917 to 1922 period. Those born in the second wave
(September 1918 to January 1919) were 1.535 times (or over 50 per cent) more likely to be
stillborn. Similarly, while those born in the second or third waves were 1.326 times (or 33
per cent) more likely to die in the neonatal period, those born in early 1919 and at risk in the
third wave were at highest risk, being 1.776 times (or over 75 per cent) more likely to die
before reaching one month of age. Those born during 1918 were 50 per cent more likely to
die between the ages of one month and one year, but the risks of post-neonatal mortality
were highest for those born between July and September 1918, who were young during
the second wave, still at risk during the third wave, and who were nearly twice as likely to
have died.
In order to help identify the ways in which infants were at risk, be it from death from
influenza itself, from some complication such as pneumonia, or via maternal health, the
analyses were performed separately for different cause of death categories.
44
Causes of
July
Au
g
ust
September
October
November
December
January
Februar
y
March
A
p
ril
May
June
0
100
200
300
percentage increase in stillbirth rate during
peak of 3rd wave for mortality at all ages
peak of 2nd wave for mortality at all ages
peak of 1st wave for mortality at all ages
Figure 8: Indexed period stillbirth rates in Derbyshire, late 1918 and early 1919 (monthly averages
for other years 1917–22 ¼ 100). (Source: Derbyshire health visitor data.)
44
Thus the risk of dying from a particular
group of causes, such as congenital malformation,
is assessed against the risk of not dying
from that group of causes. In such analyses,
infants dying from causes other than that being
examined are treated as censored (i.e. gone
out of observation) on their
death.
44
Alice Reid
death in infancy were notoriously poorly recorded in the early twentieth century, with
inaccurate, inconsistent diagnoses and a large proportion relegated to the unknown cate-
gory.
45
However, broad causal groupings can minimize these problems while still being
instructive. The problems of cause of stillbirth reporting are potentially even greater, as such
births did not have to be registered and medically certified.
46
However, a reasonably high
proportion of stillbirths in the data set have a cause attributed, and although some are rather
speculative, many others identify recognized conditions or circumstances such as prema-
turity, complications of labour, congenital malformations or implicate the ill-health of
the mother.
The ways in which influenza caused stillbirths will be considered first. Obviously
foetuses in the womb were not at risk of catching influenza in the same way that infants
July
Au
g
ust
September
October
November
December
January
Februar
y
March
A
p
ril
May
June
0
100
200
300
percentage increase in neonatal death rate
peak of 3rd wave for mortality at all ages
peak of 2nd wave for mortality at all ages
peak of 1st wave for mortality at all ages
Figure 9: Indexed cohort neonatal mortality rates in Derbyshire, late 1918 and early 1919 (monthly
averages for other years 1917–22 ¼ 100). (Source: Derbyshire health visitor data.)
45
Williams, op. cit., note 41 above, p. 68.
46
Stillbirth registration was introduced in 1927 in
England and Wales, and although from 1915 stillbirths
were supposed to be notified under the Notification of
Births (Extension) Act, it has been estimated that
around a fifth to a quarter of stillbirths were not notified.
It appears that the health visitor data set conforms
to this pattern. See Registrar-General, The
Registrar-General’s statistical review 1927, London,
HMSO, 1929, text p. 128; E A Wrigley, ‘Explaining
the rise in marital fertility in England in the
‘‘long’’ eighteenth century’, Econ. Hist. Rev., 1998,
51: 435–64, pp. 441–2; Graham Mooney,
‘Stillbirths and the measurement of urban infant
mortality rates’, Local Popul. Stud., 1994, 53:
42–52.
45
1918–1919 Influenza Pandemic and Child Health
already born were. The only way an unborn child could have been affected by the influenza
virus was if its mother were afflicted.
47
While comparatively few mothers were recorded as
having suffered from influenza, unspecified ill-health was frequently mentioned as a cause
of stillbirth, in addition to accident or shock prior to delivery and overexertion. It is reason-
able to assume that during the epidemic year a large proportion of unspecified maternal ill-
health would have been influenza. Figure 11, showing the proportions of all births
associated with maternal ill-health for each quarter of the years 1917 to 1922, suggests
that a higher proportion of stillbirths and infant deaths were attributed to maternal ill-health
during the epidemic year than in the following years (the first quarter of 1917 is unusually
high, and other high rates in 1917 and 1918 could be due to a build up in the influenza
epidemic as suggested by Johnson
48
). However the effect was not dramatic and maternal ill-
health may just have been a convenient scapegoat for an otherwise inexplicable stillbirth at
any time, an effect exacerbated during the epidemic. Table 3, showing the odds ratios for
stillbirths associated with periods of particular risk and different causal groups, while
47
There is only one documented case of
transplacental transmission of the disease although
the passage of other viruses is well accepted.
David H Yawn, Joella C Pyeatte, Stephan L Eichler,
Rafael Garcia-Bunuel, ‘Transplacental transfer of
influenza virus’, J. Am. med. Assoc., 1971, 216:
1022–23.
48
Johnson, op. cit., note 3 above, pp. 113–22.
January
February
March
April
May
June
July
August
September
October
November
December
0
100
200
300
percentage increase in post neonatal death rate
Figure 10: Indexed cohort post-neonatal mortality rates in Derbyshire, late 1918 and early 1919
(monthly averages for other years 1917–22 ¼ 100). (Source: Derbyshire health visitor data.)
46
Alice Reid
controlling for other factors, confirms the overriding importance of the health of the mother.
Infants born during the third wave of the epidemic were 1.928 times (i.e. nearly twice) as
likely to be stillborn due to maternal ill-health than infants born at other times.
Given that influenza may have provoked early labour or interruption of pregnancy, it is
also not surprising that the risk of stillbirth due to complications of pregnancy (mainly ante-
partum haemorrhage, eclampsia and placenta praevia) rose during the epidemic, although
the poor fit of this model warns against placing too much reliance on these figures. The risk
of stillbirth due to complications of labour, however, did not rise for births during the
epidemic, reflecting the more mechanical nature of such problems, which were dominated
by contracted pelvis, prolapse of cord, malpresentation, and a prolonged labour. The risk of
malformation with maternal rubella during pregnancy is well known, and there are also risks
of abnormalities with non-specific viral illnesses,
49
and some for influenza itself.
50
The
increased odds ratio for stillbirths due to congenital malformations, although not significant,
is therefore unsurprising. The lack of significance may be attributable to their small numbers
or possibly to the fact that mild abnormalities now classed under newborn encephalopathy
49
Nadia Badawi, Jennifer J Kurinczuk, John M
Keogh, Louisa M Alessandri, Fiona O’Sullivan,
Paul R Burton, Patrick J Pemberton and Fiona
J Stanley, ‘Antepartum risk factors for newborn
encephalopoathy: the western Australian
case-control study’, Br. med. J., 1998, 317:
1549–53.
50
See Coffey and Jessop, op. cit., note 31 above, pp.
935–7, and MacKenzie and Houghton, op. cit., note 30
above, pp. 356–64.
Table 2
Increases in mortality connected with being born in time periods which put infants at risk during
the 1918–19 influenza epidemic in Derbyshire: stillbirths, neonatal mortality and
post-neonatal mortality examined separately
Period of birth Odds ratio
a
Stillbirth July 1918–April 1919 1.247*
Sept. 1918–Jan. 1919 1.535***
Neonatal mortality July 1918–April 1919 1.326**
Jan. 1919–April 1919 1.776***
Post neonatal mortality 1918 1.500***
Feb. 1918 1.668*
July 1918–Sept. 1918 1.935***
a
Odds ratios give the multiplicative increase in mortality associated with period of birth,
compared to a value of 1.000 for all other months in the period 1917–22. Each odds ratio is derived
from a separate multivariate analysis (logistic analyses in the case of stillbirths, and hazards
analyses for neonatal and post-neonatal mortality), in which other variables are also controlled (see
text for details).
***Significant at 1% level.
**Significant at 5% level.
*Significant at 10% level.
Source: Derbyshire health visitor data.
47
1918–1919 Influenza Pandemic and Child Health
(seizures, abnormal consciousness, difficult respiration or feeding, abnormal tone or
reflexes) may not have been well enough defined to be classed as congenital defects
and, if there was an alternative putative reason such as the mother’s health, stillbirths
might have been attributed to another causal group.
Table 3 confirms that the additional risks of stillbirth during the influenza epidemic were
concentrated under causes specific to the mother’s health and pregnancy. Given that the
route by which influenza affected the health of unborn infants was via the mother’s health,
and that neonatal mortality is strongly dependent on the condition of the newborn infant, it
also seems plausible that the health of neonates would have been affected by maternal
health. This opens the possibility that interruption of a woman’s pregnancy due to influenza
may have resulted not in a stillbirth but in a live premature or abnormal birth, perhaps after
exposure earlier in pregnancy.
51
There may therefore have been a larger pool than usual of
particularly vulnerable infants at risk of neonatal death. Although such infants may not have
succumbed to influenza, the epidemic can be held to have contributed to their death by
making them vulnerable to other causes. Table 4 explores this possibility by showing the
odds ratios associated with birth at the key periods of the epidemic for the risk of neonatal
mortality from different causal groups.
0.0
0.5
1.0
1.5
proportion of all births associated with maternal ill-health
1917
1922
19211920
1919
1918
Figure 11: The proportion of all births in Derbyshire associated with maternal ill-health, by quarter,
1917–22. (Source: Derbyshire health visitor data.)
51
See Wynne Griffith, et al. op. cit., note 29 above.
48
Alice Reid
The most striking results in the table are those which indicate the direct and associated
deaths from the epidemic. The two and a half fold risk of neonatal death from the residual
group (in which influenza deaths were placed) associated with birth in the third wave of the
epidemic suggests that very new babies may have succumbed directly to the disease itself.
Inspection of the records suggests that in a large number of these cases the mother was also
afflicted. There was an almost identical risk of dying from pneumonia, an associated cause.
Even though influenza was not implicated in these deaths, it is very likely that the under-
lying cause was indeed the ’flu and that poor certification and recording were responsible for
underestimation of the effect of influenza.
In addition Table 4 shows that infants born in the third wave (January to April 1919) were
76 per cent more likely to have died from prematurity, wasting and congenital malforma-
tions than infants born at other times. This could be taken as support for the proposition that
the epidemic created a larger proportion of premature births. However, the fact that viruses
such as influenza are also likely to have been connected with malformations suggests
another route.
Table 5 separates the prematurity, wasting and congenital malformations group into three
and presents the odds ratios for birth during the epidemic for the risk of death from each
subcategory. This table suggests that those born during the influenza pandemic ran no
additional risk of early death from congenital malformation, and although there was an
additional risk of dying from prematurity it was not significant. For those born between
January and April 1919, however, the risk of dying in the neonatal period due to wasting was
Table 3
Increases in stillbirth rates connected with being born in time periods which put infants at
risk during the 1918–19 influenza epidemic in Derbyshire: different causes of
stillbirth examined separately
Odds ratios associated with periods of birth
a
July 1918–April 1919 Sept. 1918–Jan. 1919
All causes 1.247* 1.535***
Health of the mother 1.782*** 1.928***
Complications of pregnancy
b
2.165* 2.586**
Complications of labour 0.822 1.042
Congenital malformations 1.092 1.406
Other causes 0.997 1.397
a
Odds ratios give the multiplicative increase in mortality associated with period of birth,
compared to a value of 1.000 for all other months in the period 1917–1922. Each odds ratio is
derived from a separate multivariate logistic analysis, in which other variables are also controlled
(see text for details).
b
The fit of this model was questionable.
***Significant at 1% level.
**Significant at 5% level.
*Significant at 10% level.
Source: Derbyshire health visitor data.
49
1918–1919 Influenza Pandemic and Child Health
nearly three times higher than normal. This might suggest that infants who caught influenza
very young died from subsequent weakness, but it is also compatible with infants disad-
vantaged as a result their mothers having contracted influenza. The poor recording of the
causes of infant deaths has already been mentioned, and the younger the infant at death, the
Table 4
Increases in neonatal mortality connected with being born in time periods which put infants at
risk during the 1918–19 influenza epidemic in Derbyshire: different causes of death
examined separately
Odds ratios associated with periods of birth
a
July 1918–Jan. 1919 Jan.–April 1919
All causes 1.326** 1.776***
Prematurity, wasting, congenital malformation 1.256 1.762***
Bronchitis and pneumonia 1.624 2.444*
Complications of labour 1.110 0.000
Convulsions 1.103 0.799
Other causes (including influenza) 1.637* 2.417***
a
Odds ratios give the multiplicative increase in mortality associated with period of birth,
compared to a value of 1.000 for all other months in the period 1917–1922. Each odds ratio is
derived from a separate multivariate hazards analysis, in which other variables are also controlled
(see text for details).
***Significant at 1% level.
**Significant at 5% level.
*Significant at 10% level.
Source: Derbyshire health visitor data.
Table 5
Increases in neonatal mortality connected with being born in time periods which put infants at
risk during the 1918–19 influenza epidemic in Derbyshire: sub-categories of the prematurity,
wasting and congenital malformations cause of death examined separately
Odds ratios associated with periods of birth
a
July 1918–Jan. 1919 Jan.–April 1919
Prematurity 1.048 1.419
Congenital malformations 0.540 0.767
Wasting 2.066*** 2.902***
a
Odds ratios give the multiplicative increase in mortality associated with period of birth,
compared to a value of 1.000 for all other months in the period 1917–22. Each odds ratio is derived
from a separate multivariate hazards analysis, in which other variables are also controlled (see text
for details).
***Significant at 1% level.
**Significant at 5% level.
*Significant at 10% level.
Source: Derbyshire health visitor data.
50
Alice Reid
worse the problem. Prematurity was not well defined and, in the absence of the accurate
estimation of gestational age, is difficult to assess. Although it was often stated in con-
nection with stillbirths, it may not have been routinely noted for live births in the health
visitors’ ledgers. Infants who were born premature but who did not die immediately are
likely to have had their death recorded under some other heading, even though prematurity
may have contributed towards their death. The wasting category includes many causes
that would be perfectly compatible with premature infants: ‘‘marasmus’’, ‘‘innutrition’’,
‘‘malnutrition’’, ‘‘macerated’’, ‘‘wasting’’, ‘‘weakly’’, ‘‘delicate’’, ‘‘feeble’’, ‘‘debility’’,
‘‘inanition’’, ‘‘exhaustion’’. The lack of distinction between the causal groups, and parti-
cularly the problem with identifying premature infants, is one of the reasons for grouping
into the broader category, and also suggests that it might not be legitimate to rule out a
larger pool of premature weakly children as a cause of higher neonatal death during the
epidemic.
Prematurity and conditions within the womb are less likely to have affected post-
neonatal mortality, as the most vulnerable infants might already have died during the
neonatal period. Table 6 shows that indeed the excess risks for those born in 1918, and
particularly for those born in February and exposed during the first and second waves,
were concentrated in the risk of death from the infectious disease group, which includes
influenza. The risk of dying from these causes was two and a half times greater for
children born in 1918 than at any other time, and nearly six times greater for those born
in February. It is interesting that although there was a 33 per cent higher chance of
dying from bronchitis and pneumonia for those born during the epidemic, this was not
Table 6
Increases in post neonatal mortality connected with being born in time periods which put infants
at risk during the 1918–19 influenza epidemic in Derbyshire: different causes of death
examined separately
Odds ratios associated with periods of birth
a
Born in 1918 Born in Feb. 1918 Born July–Sept. 1918
All causes 1.500*** 1.668* 1.935***
Infectious disease (incl. influenza) 2.549*** 5.815*** 2.576***
Wasting diseases 1.946*** 2.269 4.647***
Bronchitis and pneumonia 1.331 0.992 0.851
Diarrhoeal diseases 0.824 0.000 1.468
Convulsions 1.509 1.253 2.656**
Other causes 0.995 0.772 1.192
a
Odds ratios give the multiplicative increase in mortality associated with period of birth,
compared to a value of 1.000 for all other months in the period 1917–1922. Each odds ratio is
derived from a separate multivariate hazards analysis, in which other variables are also controlled
(see text for details).
***Significant at 1% level.
**Significant at 5% level.
*Significant at 10% level.
Source: Derbyshire health visitor data.
51
1918–1919 Influenza Pandemic and Child Health
significant, perhaps because of small numbers, or perhaps because influenza was men-
tioned more often for older infants in the health visitors’ ledgers.
52
For infants exposed
during the epidemic, the risk of dying from wasting diseases remained much higher in
the post-neonatal period, nearly twice as high for those at risk during any part of the
epidemic, and nearly five times as high for those born between July and September.
There is a possibility that this can be accounted for by some weakly children who
survived into the early post-neonatal period, but this is unlikely as, when the second
month of life is excluded, the odds ratio increases to 2.191 (4.362** for those born in
February and 5.140*** for those born in the summer), suggesting that older infants were
more likely to die of wasting. These infants could have been weakened by the epidemic
and succumbed to other causes of death later. A further possibility is that infants whose
mothers had influenza were put at risk by their mother’s ill health: not directly as
stillbirths and possibly neonates were, but indirectly through a very sick mother’s
inability to feed and care for her children. Infants whose mothers have died are always
at higher risk, at least partly because of the lack of breast milk, and it is plausible that
mothers who were afflicted with influenza were forced to wean their infants earlier than
they might otherwise have done, or that their milk supply was not as plentiful or
nutritious as it would normally have been. Infants born in the summer of 1918 and
still below the normal weaning age of six to nine months at the height of the second
wave would have been particularly vulnerable, and therefore at increased risk of
mortality from wasting diseases.
0 2 4 6 8 10121416182022
age in months
0
20
40
60
80
percentage of children receiving breast milk
born June - August 1917
born June - August 1918
Figure 12: Percentage of infants in observation at each age who were still receiving breast milk:
comparing those born in Derbyshire in the summers of 1917 and 1918. (Source: Derbyshire health
visitor data.)
52
Where more than one cause of death (such as
‘‘pneumonia following influenza’’) was recorded in
the ledgers, the antecedent cause (in this case influenza)
was recorded as the primary cause.
52
Alice Reid
Figure 12 shows the percentages of infants in observation at each month whose feeding
method was known, who were still being breast fed.
53
The broken lines show those born
between June and August 1917 and demonstrate that when they were six months old, and
before the second wave of the influenza epidemic struck, over 70 per cent of children were
still receiving some breast milk. The solid lines show those born in the same months a year
later, who were still young and therefore most at risk of early weaning during the influenza
epidemic. At six months old not much more than 60 per cent of these infants were being
breastfed. There are many other influences on the duration of breast-feeding which this
graph does not take into account, so although it is not conclusive, it does suggest that ill-
health among mothers may have forced them to wean their infants earlier during the
epidemic. The fact that nearly half the monetary value of emergency help given to ’flu
victims in Manchester between 4 December 1918 and 11 January 1919 was in the form of
the dried baby milk, Glaxo, lends added weight to this suggestion.
54
Conclusions
One of the peculiarities of the 1918–19 influenza pandemic was the unusual age pattern of
incidence and mortality, hitting the usually healthy young adults in the 20 to 40 age group
most severely, in whatever part of the globe it struck. The massive relative rises in mortality
in young adults and the greater potential economic impact have led to these age groups
receiving the lion’s share of attention in the literature. Infants and young children are
traditionally a more vulnerable group, both to influenza and other forms of infectious
disease, and their relative mortality was also increased dramatically, but discussion of
the young is mostly relegated to mentions of school closures, or in the context of illness
or death to whole families. To some extent this lack of attention can be accounted for by the
lack of evidence on age-specific rates and information about the very young. The supreme
dependence of the very young on their parents, particularly their mothers, however, suggests
that high adult illness and mortality is likely to have an impact on infants and children, and
this makes discussion of the effects on infants and children all the more interesting. While
adults could be affected either directly or indirectly (via a secondary infection, a complica-
tion, or as a contributory cause), the wellbeing of infants could also be determined by their
mother’s health. This paper has provided support for the hypothesis that influenza infection
in the first or second trimesters of pregnancy can provoke premature delivery, and therefore
stillbirths or vulnerability to early death. Older infants may be disadvantaged by their ailing
mother’s inability to provide adequate care and nutrition, such as through breast-feeding. Of
course, infants out of the womb were also at risk of catching the disease, and there was a
higher risk of death from the direct effects of the ’flu itself than from the indirect effects of a
mother’s health, but it is very likely that the latter raised the death rate more than it would
otherwise have been. In a sense, therefore, increased adult mortality contributed to
increased infant mortality. If part of the increase among infants was due to the indirect
53
This includes infants who were receiving both
breast and artificial food. A similar graph can be drawn
for those receiving only breast milk which shows the
same effect.
54
Charles Graves, Invasion by virus: can it
happen again? London, Icon Books, 1969.
Other help was in the form of coal, milk and food
expenses.
53
1918–1919 Influenza Pandemic and Child Health
effects of their mothers’ illness or death, the direct effects on infants of contracting the
disease themselves must be less than the overall rise in infant mortality. The relative rise in
adult death rates during the epidemic is known to have been much greater than for infants,
and the difference between adults and children is even greater if only the effects of suffering
from the disease are considered. The virus itself therefore had an even greater proportionate
effect on young adults than is revealed by the examination of overall death rates. Anthony
Burgess, while undoubtedly unlucky to have lost his mother, was lucky to have escaped
from both death from the influenza virus and the added health and survival disadvantages of
having lost his mother. As he himself said: ‘‘I should not have been chuckling; I should have
been howling for food; perhaps the visiting neighbour who had herself just been stricken had
provided me with a bottle of Glaxo’’.
55
55
Burgess, op. cit., note 1 above, p. 18.
54
Alice Reid
