NationalLibraryOfScotland/medical-history-of-british-india huggingface dataset:
101
placed upright, their lower ends resting in a vessel of water. The line of visible
wetting rose as follows :—
Palwal Soil 24 hours
. .
69 cm.
48 „
.
.
76 „
96 „
.
.
85 „ and still higher later until a fissure in the column
interfered with the experiment.
Sand
24 hours
,
, . .
40 cm.
48 ,,
.
.
40 „
96 ,,
.
.
4 0
„
There is therefore a great difference between ( a) sand and (b) fine silt as regards
the height to which capillarity will carry up moisture. A close grained silty soil
is therefore more apt than a sandy area to become water-logged since ( a) it becomes
saturated to a greater height above the subsoil level, ( b) the closeness of its parti-
cles which make it act in this way also make it very impervious to percolation by
gravity.
Water-logging.
Summarising these facts we can see that when rain falls two forces are in action
causing any collections of water unable to drain off to sink into the soil ; these are
gravity and capillarity. The relative value of these two forces depends upon the
nature of the soil. In loose sandy soil gravity is an important force ; in
close impervious clay or silt this force acts much less effectively and capillarity
is mainly concerned in the disappearance of surface water.
When by saturation of a fine silty soil, like that of the Punjab, the power of
exercising capillarity is wholly or in part done away with, rain water sinks in
with extreme slowness.
If the subsoil water is at a depth of only a few feet the soil, even to the
very surface, has drawn up moisture and having thus lost partially or wholly its
power to absorb by capillarity is rendered extremely impervious.
When the subsoil water is on the contrary at a considerable depth, any rain
falling on the soil finds it ready to exert its full absorptive power, both gravity and
capillarity acting.
When more rain falls surface water is still acted upon by capillarity, because
the soil at a given depth is still absorbing water from the upper portions. But
if sufficient rain falls in a sufficiently short space of time, there comes about a
condition in which either the descending moisture meets with the saturated layer
above the subsoil water or owing to the depth of moist surface soil, capillarity
cannot act with sufficient speed to effect the surface and again we come to water-
logging, but in this case independently of subsoil water altogether.
When water-logging has come about and rain falls, the number of surface pools
and the time they retain water is greatly increased. There is also the fact
102
commented upon in a previous chapter that anopheles larvae are capable, if a pool
dries up, of surviving and continuing their development when more rain falls if
they are not exposed to more than a certain amount of desiccation. This time is
greatly extended in the case cf a water-logged soil.
Water-lagging therefore greatly favours the breeding of anopheles and. may,
when associated with frequent rain showers, possibly bring about an increase in
their numbers comparable with the swarming of certain other species of insects.
In the absence of rain a water-logged soil, though it allowed a certain number of
anopheles to breed, is not necessarily favourable to a great increase of the genus.
The comparative importance of such conditions as compared with the formation.
of extensive sheets of water cannot, in the absence of observations in epidemic
times, be stated.
III.—THE EFFECTS OF IRRIGATION.
Irrigation broadly speaking in the Punjab is of three types—( a) well irriga
-tion, (b) irrigation inundation canals, and (c) irrigation by the great canal systems.
The first we need. not consider here as it is presumably the form of irrigation.
least likely to affect the incidence of malaria. The second type embraces a variety
of conditions varying from the small privately-owned nullahs to larger canals
resembling the canals of the great systems. The conditions at Wegowal point to
the serious effects which flooding from these canals may give rise to. A flooded.
tract by a canal of this kind was also seen in the Bhera thana, many acres being con-
verted into what seemed to be a semi-permanent swamp. Such canals however
exist only over a comparatively insignifi cant proportion of the Punjab and scarcely
concern us in our present effort to arrive at the factors concerned in the great epi
demics.
The Great Canal Systems.
Originating from the river Jumna close to where this issues from the hills is.
the Western Jumna Canal. This canal after running for about 50 miles without
many branches breaks up into a net-work of distributaries over the Karnal, Robtak
and Hissar districts. From the Sutlej at Ruper issues the Sirhind Canal which,.
forming a great loop with its convexity facing south, sends off a net-work of distri-
butaries to supply the western half of Ludhiana, the native state of Patiala and the
southern portion of Ferozepore. No other system occurs until the Beas is crossed
and the Bari Doab system is reached. There is thus a large tract embracing the
whole of Jullunder and Hoshiapur, the eastern half of Ludhiana, and much of the
Umballa district which is scarcely touched by any irrigation system properly so
called. InUmballa and Hoshiapur however much minor irrigation is carried on.
Beyond the Bari Doab there is again a break in the irrigated area occupying
Sialkot and a portion of Gujranwala. Beyond this there is a broad irrigated tract
extending as far as the Jhelum.
103
A moment's consideration will show that epidemic prevalence is in no way due
to these great irrigation works. It would almost seem that whilst the irrigated
tracts are often comparatively exempt from epidemic influences, parts like Sialkot,
eastern Ludhiana and Umballa, which are not, irrigated by these systems, suffer
especially severely. The real reason of this is of course more or less obvious, the
canals irrigating tracts which on account of their natural dryness are compara-
tively unsuited to epidemic conditions. If any relation exists between irrigation
and epidemic prevalence it can only be that irrigation may render a tract more
liable than it would normally be to influences bringing about epidemics.
Canals and Subsoil Water.
The Bari Doab and especially the district around Amritsar is frequently cited
as an over-irrigated tract. It is also stated that the present condition of high
subsoil water level is entirely due to this irrigation continued over many years.
Even so, with the exception of Amritsar city, we do not find this district so very
liable to severe epidemics and the southern portion of the tract will be seen
from the composite map (Map 11) to have been comparatively little affected by
epidemic conditions.
Canal Overflows.
If canals are seriously affecting the epidemic incidence in any tract it is very
probable that it is due to overflows. By this I do not mean small leaks but the
formation of extensive sheets of water which in a sense reproduce the conditions
suitable for epidemic intensity.
I V . — E P I D E M I C R E A C T I O N .
By noting the behaviour of different areas to epidemic conditions we may
distinguish the following :
—
1. Tracts which although they may not exhibit epidemic conditions for years
are in some way so predisposed to them that on a certain minimum of rainfall
they will (some other necessary factor which we shall discuss later being present)
become the seat of epidemic malaria. It will be quite clear from the maps of
epidemic areas in different years that of such a nature are portions of riverains,
their behaviour in this respect either causing them to be picked out as areas of
slight intensity when at a distance from the epidemic nucleus or as areas of special
intensity when within the zone of severe epidemic conditions. Notably among
such areas are the Jhelum riverain at Bhera, the Sutlej riverain near Ferozepore,
the old bed of the Beas near Kasur, the neighbourhood of Thanda Urmar and so on.
104
In addition to tracts of this nature there are others which are not obviously
riverain but nevertheless behave in the same way. One such tract lies to the
north-west of Lahore (Muridke, Kamoke, etc.,) and was well picked out in the
1908 epidemic. In reality it is a broad low-lying area at the foot, so to speak, of
the district of Sialkot so that it receives much of the drainage from this district.
Another type of tract similar to the la,st mentioned in regard to its behaviour
to epidemic disease though not in physical features is that to which Gujrat and
the thanas along the foot of the Siwalik hills in Hoshiapur belong.
Such tracts not only easily become affected but exhibit a high degree of epi-
demic intensity, the death rate generally being during the epidemic months
about 400 per mille.
2. Tracts which are possessed of the necessary topographical features but
have never or very seldom exhibited an epidemic mortality because they lie
beyond the range of the necessary monsoon rainfall. Of such a nature must be
large portions of the western Punjab.
3. Tracts which from their physical features are less easily affected by epi-
demic conditions and in which the death rate is usually less than in water-
logged tracts under similar epidemic conditions. Tracts of this nature when they
occur beyond the zone of heaviest rainfall exhibit their relative powers of resist-
ance very strikingly. After passing sufficiently west they are often exempt from
epidemic malaria whilst the riverains are still liable to be affected. But the
protection afforded by physical features once within the zone of full epidemic
influence is comparatively small. There is scarcely any part of the eastern sub-
montane tract which has not at some time or another become part of an epidemic
focus. If we search for a tract which within the last forty years has never
exhibited a death rate due to epidemic malaria of over 10 times the normal we
shall find that over the large area shown in Map 11 not a single thana has escaped.
It we similarly look for a thana which has never been subjected to epidemic
conditions of a severity represented by the epidemic figure of 7, we shall find the
whole of Gujrat, Sialkot, Gurdaspur and Hoshiapur and most of Gujranwala,
Amritsar, Ludhiana and Karnal, as well as the whole of the south-eastern
extremity of the Punjab, closed to us. In other words, within these areas it is
not a matter of the local conditions of particular thanas which is concerned but
simply of the areas chosen by epidemics.
A very reasonable presumption, looking at Map 11, is that, given sufficient
rainfall, etc., any part of the submontane tract is capable of exhibiting epidemic
conditions of the utmost severity.
105
CHAPTER XIII.
The Human Factor.
The researches of Celli in Italy and of Dr. Bentley and myself in India show
the necessity of considering the conditions affecting the human host as well as
those affecting the numbers and life generally of the mosquito. In dealing with
epidemic conditions associated with high mortality this is especially necessary.
I.—MORTALITY INCIDENCE AMONG DIFFERENT CLASSES.
The following table gives the mortality among Mahomedans and Hindus at
Amritsar during the epidemic years 1908, 1892, 1881.
September.
October.
November.
M.
H.
M.
H.
M.
H.
1908
.
.
.
.
.
.
.
.
62.3
86.6
390.3
203.0 329.4
181.5
1892
.
.
.
.
.
.
.
. 123.6
79.9
168.5
122.1
126.4
99.3
1881
.
.
.
.
.
.
.
. 348.6
190.0
548.9
318.5
324.8
223.0
The increased rate among the Mahomedans who form the bulk of the poorer
classes is very noticeable. The very high rates in 1881 were associated with
distress among the same class, largely Kashmiri shawl weavers, etc., who were
adversely influenced by decay of the shawl industry.
The most affected parts of the city in 1908 were, we have seen, Khazana and
Mahan Singh. Both these sections are noticeable for the large proportion of low
class Mahomedans and Kashmiris. So far as one could judge from impressions
gained during investigations at Amritsar, it was the Kashmiris who also suffered
most severely in 1908.
A feature of the mortality at Amritsar was the large relative proportion of
deaths amongst adults as compared with many other places.
At Delhi in the city proper those wards inhabited by the poorest class
suffered the most severely. Ward XI, where mortality was greatest, is mainly
inhabited by the very poor.
At Palwal the large proportion of the population who were of the lowest
social status was very marked, quite large quarters being composed entirely of
Chamars and similar low castes. The mortality was also as at Amritsar very great
among adults.
Bhera seemed a well-to-do town, though this impression was modified by closer
acquaintance. It was noticeable here that the adult death rate was not very high.
P
106
Among poor and dependent classes we therefore get a higher mortality than
among the well-to-do. How far this is due to the less deadly effects of malaria or
to an increased indirect action of the disease it is impossible to say. The propor-
tion of adult deaths would seem to have some significance, but the matter requires
further study. The important pointi s
t h a t i n a r r i v i n g a t a n e s t i m a t e o f t h e
effects of malaria in different towns and villages, it is necessary to recognise and
allow for this class coefficient.
II.—SPLEEN RATE AND SOCIAL STATUS.
An analysis of observation upon enlargement of the spleen in Amritsar and
Delhi gave the following results :—
AMRITSAR —
Khatris, Aroras, Brahmans
.
.
. 0
0.9 25.6 19.5 54
46 % 348
Talis, Kamiars Oil-people, potters, etc. . 1
7.5 38.1 27.2 26.2 73 % 294
Cultivator Class, including Cow-keepers . 4.1 10.9 29.9 25.8 29.9 70.9% 147
Low class Kashmiris and Sweepers
. 2.5 10.7 40.5 25.1 21.1 78.9% 279
DELHI —
Brahmans, Banyas, etc.
.
.
. 0 5.0 18.0 17.0 60.0 40.0%
108
Lohars, Dhobies, etc.
.
.
. 0
8.0 36.0 26.0 30.0 70.0%
50
Chamars, Sweepers
.
.
.
. 9 12.0 49.0 11.0 18.0 82.0%
63
These data are to a considerable extent influenced by the fact that the better
class live in more healthy parts of the towns. But in the following rates, which
are those for rural areas, this cannot seriously influence the figures :—
PALWAL —
Brahmans, Banyas
.
.
.
. 0 13.5 40.6 25.0 20.8 79.2%
96
Cultivators (Rajputs and Jats)
.
. 5 18.0 38.4 21.8 16.6 83.1%
78
Telis, Chamars and Sweepers
.
. 4 18.2 36.4 13.6 10.0 90.0%
110
ATARI —
Arains, Lohars, etc.
.
.
.
. .2 5.5 38.2 40.0 16.4 83.6%
55
Chamars, Sweepers
.
.
.
. .1 12.3 47.7 20.0 10.8 89.2%
65
MIAN MIR
—
Sikhs, Banyas
.
.
.
.
. 0 2.0 30.0 26.0 39.0 61.0%
126
Chamars, Sweepers
.
.
.
. 0 10.0 44.0 24.0 21.0 79.0%
57
SHAHPUR —
Aroras and Raolis .
.
.
.
. 1
3.0 27.0 14.6 54.2 45.8%
96
Low class cultivators
.
.
.
. 0 12.3 18.8 24.6 24.0 76.0% 65
GUJRAT —
Aroras
.
.
.
.
.
. 0
0
5.0
5.0 16.0 38.5% 26
Cultivators
.
.
.
.
.
. 0 7.7
19.6 19.0 53.8 46.2% 117
Lohars, Tarkhans .
.
.
.
. .2 5.0
11.3 29.5 52.3 47.7%
44
Telis, Mochis and Sweepers
.
.
. 1 4.0
34.3 18.0 41.7 67.0% 67
107
These data show clearly the influence of low social status on the spleen rate.
They also show the peculiar high rate common among the " cultivator class."
This same high rate amongst this class is also seen in the Amritsar figures.
III.—SCARCITY.
Though trade, etc., in the Punjab is undergoing considerable expansion and
the building of railways and other works is progressively increasing, it is almost
certain that this is not directly related to the great epidemic conditions we are dis-
cussing.
The distribution of the epidemics shows very clearly that the conditions lead-
ing to epidemic malaria were very widespread and had been exerted at intervals
as far back as we have records of the Punjab. It is necessary therefore to con-
sider whether there were not influences affecting the general population which
may have to be taken into account.
At Amritsar it was clear that there were all the possibilities of an exaggerated
human factor. It seems generally acknowledged that among the labouring and
artizan classes in Amritsar City, especially among the Kashmiris, the pinch of
poverty is severely felt. The latter class especially is apparently living under
conditions which favour the continuance of residual infection. 1
At Palwal and Delhi the presence of poverty turned one's attention to more
general conditions which we may sum up under the term " scarcity."
The question of food and diet is too complicated to be discussed adequately in
the present report. But it became evident, as the enquiry proceeded, that a full
dietary, as understood by the well-fed European, falls to the lot of but few of the
poorer classes, and that in times of scarcity these are accustomed to adapt them-
selves to circumstances by proportionately restricting the amount of the food they take.
The extent to which this state of affairs seemed to exist was sufficient to show that,
if the human factor were at work, it was in the form of a proportionate stress
upon the whole population, and that one must look for its most marked effects in
years of scarcity.
We have had ample evidence that epidemics are determined by rainfall, and
though we cannot predict in any particular year what a heavy rainfall will bring
about, it seems certain that a deficient fall is never associated with severe epidemic
conditions.
Even if scarcity is in reality involved in epidemic causation, we should not
expect to find it acting in the absence of the necessary factor of rainfall. We must
not look also for the effect of famine in this respect in the famine districts at the
time of the famine, for at this time the essential factor, excess of rainfall, is absent.
1 Vide a paper by Christophers and Bentley " The Human Factor," read at the Bombay Medical
Congress, 1909.
P2
108
But if heavy rain were to fall upon a famine-stricken district, we might then reason-
ably expect this to be followed by severe epidemic conditions.
That the most severe epidemics follow very frequently this sequence, is
apparently the general experience of all who have had intimate acquaintance with
the Punjab. The following abstract from the Gurgaon Gazetteer gives a graphic
account of the 1879 epidemic which followed the famine year of 1878 : —
" In the beginning of the year 1877 the condition of the district as a whole
was unusually prosperous. There had been no serious drought for
eight years and the harvests had been almost without exception up to
or above the average for at least five years. There had been no serious
mortality of men or cattle for some years ; and in population, extent of
cultivation and irrigation, number of cattle and amount of accumu-
lated capital, the district was probably richer than it had ever been
before. But the rains of 1877 were very scanty in amount and very
inopportune in their distribution ; the autumn crop of 1877 was a com-
plete failure and the following spring crop very poor. Four-fifths of
the district presented the appearance of a barren desert, and the usual
growth of grass and fodder entirely failed. The supply of fodder avail-
able was soon consumed, and even the dry thatch of deserted huts was
pulled out, and chopped up, and given to the cattle as fodder mixed
with the leaves of trees as a last resource for keeping them alive.
During the cold weather the cattle died rapidly and in great numbers,
and heaps of bones lying round nearly every village attested the great
mortality. It was estimated that nearly half of the 300,000 cattle in
the district died of starvation in that one year, a loss to the peasantry
equivalent to 15 lakhs of rupees or more than a year's land revenue of
the district. The scarcity caused by the failure of harvests hardly
deepened into actual famine, although there were some deaths from
starvation, and a large portion of the population was greatly weakened
by want ; but it was followed in 1878 and 1879 by a dreadful epidemic
of fever, and in those two years 103,000 persons or more than a seventh
of the total population died ; the death rate per thousand per annum
was 68 in 1878, and 81 in 1879, and the abnormal mortality of those
years was more than 60,000 persons.
The italics are mine.
In regard to an increase of mortality in Hissar in 1897 the Famine Com-
missioners are quoted in the Census of India, p. 67, as attributing this to fever "of
the ordinary malarial type which always occurs when a year of heavymonsoon
rainfall succeeds a year of drought, " and they add that the number of deaths
109
" wa s i nc r e a s e d by t he e nf e e bl e me nt of he a l t h whi c h a pr ol onge d pe r i od of
prixation had produced."
In the 1900 epidemic the Famine Commissioners of 1901 found that " much
of the mortality was due to an unusually unhealthy autumn acting upon a popu-
lation predisposed to disease by privation."
In the Punjab severe famines have occurred in 1860-1861, 1868-1869, 1877-
1878, 1895-1896 and in 1899-1900.
For the years 1860-1861 there are no records of mortality, in 1868 deaths
from fever in October and November were only 31,099, but in the year following
the famine 1869 they rose to 116,540 or, considering the registration at that time,
a rate characteristic of a first class epidemic. In 1877 deaths in the two months
noted above only reached 38,837. In the year following they were 180,356, this
being one of the worst epidemics the Punjab has ever suffered from. In October and
November 1896 deaths were 73,239, the year following they were 141,573. Follow-
ing the year 1899 with 69,200 deaths from fever comes 1900 with a total number
of deaths in the two months of 254,580.
Each of the four great famine periods for which we have any records was then
followed by " fever years." Even if we look at the total deaths from all causes,
we shall see that the number of deaths due to the famine was negligible when com-
pared with that due to the fever which followed.
The effect of famine upon the population was therefore not directly the most
important cause of death. On the other hand, one may justly surmise that in these
instances malaria merely reaped a harvest prepared for it by the famine.
These facts certainly show that there may be a very direct connection between
the actual famine or very severe scarcity and epidemics. But we should not be
justified in assuming that all epidemic years are of this class. As a matter of fact
out of the twelve or so epidemics of which we have records only four can be
considered as famine epidemics.
As years have advanced it has become more and more impossible for famines
to manifest themselves, and even if several monsoons partially fail it is usually
scarcity rather than famine that ensues. But if actual famine may be a precursor
of epidemics, we may reasonably expect to be able to trace the effects of the
mitigated condition of scarcity. This is however a difficult task, for it is clear we
must know something about local as well as general conditions of prosperity or
the reverse before we can hope to be very successful, and this knowledge is not very
easy to get at.
IV.—RELATION OF PRICE OF FOOD STUFFS TO EPIDEMIC CONDITIONS.
The most obvious method of getting a general idea of the prevalence of ad-
verse or prosperous conditions at different times is by examining the fluctuations