experience on this point during many years and in many
different countries, and have only once been infected, and that
at a time when we did not know how the infection is produced.
288 PREVENTION [Sect.
I always rely upon the possession of four articles, namely, a
good bed-net, costing about eight shillings, a small hand-net
for catching mosquitos, costing about one shilling, a palm leaf
fan, costing one penny, and a bottle of quinine. With these
articles the chances of becoming infected are reduced enormously
ā especially if a little common sense and care are added to
the stock.
I cannot speak too highly for the ordinary bed-net, if used
as directed in section 34 (i). Anophelines almost always bite
at night. If the number of bites received by two individuals,
one of whom always sleeps in a bed-net, while the other does
not do so, could be strictly estimated, I think it would be found
that the latter receives only about 10% of the number of bites
inflicted upon the other. When a person is walking about in
the day or in the evening he is not nearly so accessible to any
species of mosquito as when he lies still and unconscious in
sleep. It is therefore almost certain that the large majority of
inoculations occur during sleep, and hence, obviously, protection
during sleep will prevent a very large proportion of them.
Moreover, I have frequently found that persons who despise
bed-nets, as many sportsmen, soldiers, planters and others are
apt to do, are very prone to suffer from malaria. So are those
who use bed-nets carelessly. After service in India, where most
people are wise enough to guard themselves in this manner, I
was much struck by the negligence on this point of Europeans
in West Africa. There can be little doubt that the comparative
good or bad health of Europeans in many parts of the world
depends very much on the intelligence which they display in
this matter ā which seems such a small one to thoughtless
people. Fortunately, the public have now been awakened, and
I have even heard of several shipping and business firms who
are wise enough to hold their employees responsible for
becoming infected, unless they can show that they have used
every precaution. This would be a very good plan to adopt
generally, even by governments and military authorities.
37] MEASURES FOR PERSONAL PROPHYLAXIS 289
Next to the bed-net, I attach most value to the small palm
leaf hand-fan ; as stated above, I much prefer the use of it to
thick gloves, mosquito-boots, etc. Here again the more manly,
but often more unwise person, is apt to despise the suggestions
of common sense.
The small hand-net is almost equally valuable. If I sit
down to write or read, I am generally visited at once by a
number of hungry suitors, and I like to take the precaution
of catching and killing the lot before proceeding to my task.
In fact I am not ashamed to confess that I take both a hand-
net and a hand-fan to bed with me, in order to deal with any
stray mosquito which may enter with me !
Protected by these humble means, I do not often have
recourse to quinine. In most places in the tropics where large
numbers of Europeans are called upon to live, the continuous
use of quinine is scarcely demanded. For example, in the
Indian cantonments, or the principal towns and settlements in
other tropical countries, the chances of infection are too small
to compensate for the discomforts caused by the drug, even
when given in the best form and in the best way. It is, how-
ever, another matter when one is obliged to sleep in places of
high endemicity ; and here we should always use the drug.
Medical men can often be guided also by the great prevalence
of Anophelines ; and in fact many of the general public are
now beginning to recognise these dangerous insects by their
attitude and the spots on their wings. If exposed in this
manner, or if I think that I may have been bitten by infected
mosquitos, I take the drug daily for about a fortnight in doses
of between 5-10 grains (1/3 to 2/3 grammes). I know that this
will not absolutely insure destruction of any protospores which
may have entered, but I trust to luck that this has been the
case. Anyway, I think that the inoculated germs have been so
much reduced in numbers that (for certain reasons of my own)
I think they are not likely to produce a very severe illness,
T
290 PREVENTION [Sect.
even if they do reach the fever h'mit. Then also I am otherwise
protected by netting.
How far we should recommend what some may consider to
be reprehensible carelessness for the general public is another
question. The medical man does not always adopt for him-
self the advice which he gives to his patients ; and I therefore
prefer to leave further details under this head to the reader.
The European in the tropics must be told that he cannot
insure himself against infection to an absolute certainty,
however careful he may be. By bad luck he may be bitten
when least expecting it, and by good luck he may escape
altogether, just as the soldier may receive or escape the fatal
bullet in battle. Other precautions remain to be mentioned.
If we can select our place of residence, we should, of course,
never live in proximity to native locations, or to marshes, or in
old tumble-down thatched houses, or (very frequently) in dirty
hotels. One does not therefore always welcome the hospitality
of residents, however well meaning it may be. For travellers
it is most important to recommend that they shall not go and
live inside village houses ; they should always endeavour to
pitch tents, both for themselves and for their followers, in
appropriate country at some distance. Of course travellers
should always be provided with mosquito-proof tents, both for
themselves and for their men,
(2), Domestic precautions. ā The head of a house should
enforce the various personal measures for the whole of his
family on the lines just given. He should also try to screen
a portion of his house. In many places this will be difficult,
because in the tropics at least occupiers do not own their
own houses and owners are generally averse to paying for
such screening. But it does not cost much to screen a small
corner of a veranda for sitting in.
Next to nets, I advocate the more general use of punkas or
fans. A comparison of the life of Europeans in India with it
in many other tropical countries will force us to admit their
37] CHILDREN AND TROOPS 291
great value. Malarial infection of Europeans is very rare in
Indian cantonments, where they use punkas almost day and
night, but it is common enough among planters, who are apt
to neglect them. I really think that punkas prevent some-
thing like 50 to 70% of infection. Moreover, they keep the
body cool and vigorous, while without them we remain covered
with perspiration and tormented by mosquitos all day long.
So convinced am I of the value of punkas or fans for general
hygienic reasons that I would advocate the use of them even
in places where every mosquito has been banished.
The question of prevention for European cJiildren in the
tropics is of the greatest importance. The difficulty of rearing
them is due, I think, partly to the great heat, partly to malaria,
and partly to various entozoa and other diseases. Those who
can afford screening and punkas should therefore employ them
for their children at whatever cost. If they cannot afford them,
they should not bring their children to the tropics. The habitual
use of prophylactic quinine is seldom seen among European
children in the tropics, and I doubt whether it can be generally
recommended. In fact, if such use is actually required, the place
should be considered too malarious for children. Of course it
is another matter if children have already become infected.
(3). Troops on service. ā The amount of baggage allowed is
always very small, but the last article to be dispensed with
should be the bed-net. In my opinion the military authorities
should make all efforts to provide every man with one, because
the cost due to loss of strength in consequence of invaliding
from malaria must always be vastly in excess of that of the
purchase and transport of nets. The disease has caused well-
known disasters to troops, as in the British Walcheren expedi-
tion and the French expeditions in Madagascar (section 60).
On the other hand, the American troops in the Philippines used
nets and admitted their great value. Where the authorities
fail in providing them the wise soldier will do well to follow the
old maxim of " self-help." A daily quinine ration of say 5 grains
292 PREVENTION [Sect.
every morning should also be insisted upon, together with the
rigorous use of nets. I scarcely think that gloves and veils,
such as Laveran figures as used among the Japanese troops,
are so urgently demanded ā at least in the tropics, where they
would be nearly intolerable. The Medical Department has the
care of choice of proper bivouacs and quarters.^
(4). Ships. ā I always carry a net which can, if required, be
hung over the bunk. Ships in the tropics often delay for
hours or days in port, and are frequently visited by swarms
of mosquitos. Of course, all ships owned by companies who
possess any degree of humanity and intelligence should be
invariably screened against mosquitos in the manner shown
by Dr Wolferstan Thomas (section 46).
Quinine should be always given to the crew on arrival at
the first malarious port, and for at least one month after leaving
the last one, if the voyage lasts so long. The great mistake
of stopping the drug on departure from the malarious coast is
often, indeed generally, made. Many of our nautical patients
in Liverpool give histories of having been attacked for the first
time when nearing the British coast ā that is, their infections
had been received weeks previously, but had been suppressed
by the drug until the use of it was abandoned.
(5). Hospitals and asylums. ā Here quinine cannot be given
without interfering with the treatment of the various kinds
of disease present. The superintendent must see to it that
mosquitos are not being bred within the hospital premises ;
but unless mosquito reduction has been adopted for a con-
siderable radius outside the institution, screening should be
adopted as well. Hospitals with crowded, unprotected wards
furnish the worst examples of congregate sleeping (section 28
(3)), so favourable to the mosquito transference of several
diseases. For example, dengue prevailed greatly in an un-
protected hospital in the Philippines, while it was absent from
a protected one ; and I have frequently found filariae and
^ See destruction of adult mosquitos, p. 362.
37] BARRACKS 293
Plasmodia in hospital mosquitos. In fact the dangers are so
great that it is perhaps better to advise that every hospital
should be screened whether mosquito reduction is carried out
or not. A mosquito - infested hospital is a most disgraceful
thing. The miserable defenceless people it contains are in-
fected in the very place where they have come to be cured,
and there is no excuse for it.
(6). Barracks. ā Unless mosquito reduction can be rendered
very thorough, the best plan is perhaps to employ screening as
well. Probably most of the inoculations occur at night, largely
in consequence of the congregate sleeping usually adopted in
barracks. The cost of death and invaliding of soldiers is
probably far in excess of that of screening. Bed-nets are now
being often used or advocated, even for native soldiers ; and I
have heard of several cases where officers have helped their men
to purchase them. But surely it is the duty of the military
authorities to provide screening instead. Enormous sums are
frequently wasted on the erection of new barracks ā sums which
would have sufficed to screen all the barracks in a country.
The neglect on this point is simply marvellous. In one case,
known to me personally, a serious epidemic of malaria occurred
because the authorities were disputing as to who should pay for
the hooks required to hang the bed-nets (already purchased !).
Several of the men died, and a number were invalided at a cost
which afterwards sufficed to drain the whole neighbourhood.
Punkas pulled by machinery have long been in use in many
military hospitals and barracks in India.
Unless screening is very perfect, great care must be taken to
complete the extermination of the parasites in infected soldiers.
In any case this is necessary in order to maintain the effec-
tive fighting strength, because soldiers " soaked " with malaria
are only a source of expense in war. I doubt whether the
six weeks' treatment used in India is quite sufficient.^
Of course a large proportion of the infections among troops
^ See H. H. Johnston, Brit. Med. Journ., 15th August 1908.
294 PREVENTION [Sect.
are often contracted outside barracks. The question then
becomes one of public prophylaxis (section 39).
The quarters of officers and families should, in my opinion,
be always screened unless mosquito reduction is very perfect.
In the old days, in British possessions, large areas round
barracks were kept strictly under the cantonment authorities,
who refused to allow the general populace to live in them.
Unfortunately, owing to the pernicious sentimental outcries
which are proving so destructive to vigour and prosperity, this
wise rule is now tending to fall out of use ; filthy huts spring up
close to the barracks ; the troops become heavily infected with
malaria and other diseases ; and the nation which gives way to
this brainless folly has to pay much more for its military service,
and may have to pay still more, some day, for military defeat.
(7). Prisons. ā The prisoners are taken from the lowest
populace, and are being constantly changed as sentences
expire. Hence large numbers of them are infected outside,
and the principal measure is case reduction. In addition to
this, screening or mosquito reduction, or both, should be
adopted according to circumstances.
(8). Schools. ā Boarding schools are scarce in malarious
countries. Day schools give a most valuable opportunity, not
only for dealing with malaria by case reduction, but also for
measuring it ; but this matter is part of the general plan of
campaign (section 40 (6)),
(9). General rules. ā In all matters of domestic prophylaxis
it is wise to remember the following rules (which cannot be
repeated too often) : ā {a) unless there is strong prima facie
reason to believe that cheap measures must fail, always begin
with them before attempting more expensive ones ; and {h) do
not adopt any measure until careful examination has proved
the necessity for it. For example, I have seen and heard of
expensive screening being installed {a) where a little mosquito
brigade work would have cleared the mosquitos entirely, and {b)
where most of the infections were really being acquired outside.
38] SANITARY AXIOMS 295
38. General Sanitary Axioms. ā Before we consider the
complex subject of public malaria prevention, it is advisable
to state the following series of propositions regarding the pre-
vention of all diseases.
(i). Widespread diseases, especially endemic diseases, cause
much pain, sorrow, expense and loss of prosperity
to the people.
(2). Next to the maintenance of the State, it is the duty
of scientific governments to investigate their mode
of propagation, and to endeavour to control them.
(3). For economic reasons alone, governments are justified
in spending for the prevention of such diseases a
sum of money equal to the loss which the diseases
inflict upon the people.
(4). The amount of money spent on the prevention of various
diseases should, ceteris paribus, be proportioned to
the amount of sickness and mortality caused by each.
(5). It is the duty of governments to make and to enforce
ordinances required for the prevention of diseases ;
and of the people to submit to them.
(6). Cete7'is paribus, that sanitary measure is the wisest
which causes the public the least inconvenience.
(7). Ceteris paribus, that measure is the most practicable
which can be carried out by governments without
making any demands at all on the thoughts, efforts
or compliance of private persons.
(8). Ceteris paribus, that measure is the most economical
which confers, for unit of cost, the widest benefits
on the public.
(9). For the prevention of diseases on a large scale a suit-
able expert organisation is always required.
(10). It is always advisable to carry out accurate and
repeated measurements of the prevalence of the
disease which we propose to prevent ; of the cost
of the adopted measures ; and of their results.
296 PREVENTION [Sect.
Written out in this manner these statements appear trite
enough ; but in my experience every one of them is forgotten
in actual administration. Thus few persons remember the first
axiom ā until they themselves are taken ill. Few governments
really attend to the second one. Scarcely any one has con-
ceived the simple idea contained in the third, and it is the rule
to grudge spending a hundred pounds for a disease which costs
thousands. Dramatic diseases interest many, while common
ones are forgotten ; and the remaining axioms are too often
overlooked even by those who direct or discuss sanitary work.
39. Selection of Measures for Public Prevention.ā From
the fundamental reasoning in sections 28 and 33, and also from
general experience in many countries during the last ten years,
we are now probably justified in making the following state-
ments : ā That malaria can be completely extirpated in a locality
by the complete adoption of any one of the three great pre-
ventive measures, namely, protection, mosquito reductioti, and
treatment. That is to say, if every person in the community
could be fully guarded against mosquito bites, or if every
Anopheline could be banished, or if every infected person could
be thoroughly treated from the beginning of his case, then each
of these measures ought to suffice by itself to banish the disease
entirely. Moreover, if we could use two of the measures, or all
of them, the result would be still more assured.
But, obviously, it will never be possible in any general
community to adopt or to enforce any one of these measures
completely. Thus, however carefully mosquito-nets or screening
are used, many people will still continue to be bitten occasion-
ally, so long as the mosquitos are allowed to remain. Again,
however carefully we may destroy every mosquito which we
can catch, or every larva, or remove the principal breeding-
places, still, a few insects and breeding-places are sure to escape
us. Thirdly, however strongly we may urge suitable treatment
of all infected persons, a few are sure to resist it, and to
39] MEASURES FOR PUBLIC PREVENTION 297
spread the disease if any Anophelines are left. Hence, though
theoretically possible, the complete use of any one of the
measures is not really practicable.
Fortunately, however, we can see by careful consideration
of the principles laid down in section 28 that complete eradica-
tion of malaria may still be possible by the adoption of each
measure by itself, even if that measure is not completely given
effect to. By that section we see that the static malaria
(section 30) will tend to vanish, not only if all the factors of the
equation are rendered absolutely prohibitive, but also if they
are reduced to a certain figure ; that is, if the new infections
can no longer keep pace with the natural recoveries. This
important and encouraging law has been well exemplified in
Great Britain, from which the disease has entirely disappeared
owing to partial and indeed almost unconscious agencies, as
described in section 30 (21).
Lastly, we can understand from the same reasoning that a
partial adoption of any one of the measures, though it may
not banish malaria absolutely, is still likely, or indeed certain,
to make some reduction in the disease provided that the other
factors remain unchanged.
All these truths still continue to apply if we adopt not one
single measure, but several combined. Thus it may well be
that an extremely partial application of two of the measures
will produce results as good as a less partial application of one
of them would have done ; and this fact may help us to do the
work much more economically.
Thus the head of a sanitary department who intends to
carry out a large campaign is fortunately able to avail himself
of several measures or combination of measures, by any one of
which his purpose may be effected. But he has to consider
means as well as objects : his duty to his Government demands
that he should spend as little money as possible, and his duty
to the people demands that he should not trouble them too
much. Still more important, the various measures are more or
298 PREVENTION [Sect.
less practicable according to a number of local conditions, all
of which must be carefully considered by him before he comes
to a decision. In practical sanitary politics, therefore, the mere
enumeration and general description of the various measures
are quite insufficient, and we are obliged to discuss with great
care their relative values under different circumstances. The
reader can assure himself still further of this, by studying the
numerous contributions given by the most eminent men in
the following chapter. He will see that different measures
are being adopted in different countries. In some countries,
especially Panama, Egypt, Durban and the Federated Malay
States, mosquito reduction is the principal measure. In others,
especially Italy, Greece and the German and French possessions,
prevention by treatment is the favourite remedy ; and in other
places combined measures are in use. In fact there has been
much discussion upon this point during the last ten years ;
some urge one measure and some urge others ā each being
guided by his own experience in his own malarious country.
The truth is that all the measures are good and useful, and
that each is most suitable under certain circumstances. The
subject is evidently a complex one. I will try to make the
issues as clear as possible by supposing at first that each
measure is to be adopted by itself alone.
Protection (section 34) requires the use of bed-nets, screen-
ing, fans and some other devices. It demands an entire
concurrence of the people who are to be protected. Probably
no government can force the public to protect themselves.
Although the rich may be quite willing to do so by bed-nets
or screening, the poor will generally refuse the expense incurred.
The cost of a good bed - net is, for instance, equal to the
monthly pay of a day labourer in India. The cost of screen-
ing a house completely is often more than a tenant cares to
incur, and the house owner generally refuses to undertake it
for tenants who occupy their houses on short leases (as gener-
ally happens in the tropics). Punkas and fans are scarcely
39] PROTECTION 299
practicable for the poor, and medicinal culicifuges are of little
value. In most countries the poor, especially in rural districts,
are badly housed in huts which are everywhere permeable to
mosquitos. To protect such houses by any known means will
generally cost as much as rebuilding the whole house. Even
if the state would be willing to provide every householder with
a bed-net for himself and his family, it would still have to make
arrangements for the constant repair of them, while they would
often remain unused. We can scarcely expect that poor
families, living crowded together in a single chamber, will ever
exert themselves to use mechanical protection in a careful way.
But even with the most complete protection of houses, people
will still be subject to being bitten out-of-doors.
This, however, is to look at the subject only from the darker
side. As already stated, even a partial protection is quite
likely to have an immense effect on the malaria. Even if only
a proportion of the people could be persuaded to use an)- care
in protection, doubtless the new infections would be reduced so
much that the static malaria might either disappear entirely or
become very small. It is, therefore, most advisable to urge pro-
tection as strongly as possible ; to advocate suitable housing
for the poor ; and to post notices for the information of the
public regarding the dangers of being bitten by mosquitos.
We see, then, that the measure of general protection against
mosquitos is scarcely capable of more than a very partial
adoption by the public. As a Government measure it is