Chapter VII: On the Prevention of Malaria (2)

Mosquitoes are always greatly attracted by draperies, especially those of dark colour, and the fact may be utilised to trap them by means of deep bags of black gauze (_chiffon_), the mouths of which are held open by an oval loop of cane, or some such material. Such bags, if hung up mouth down-wards in tempting dark corners, will usually be found swarming with mosquitoes each morning, and the insects can easily be killed by crumpling the bag in the hands and then shaking out the dead insects.

By working on the above lines, especially where one has the co-operation of neighbours, it is in all cases quite possible to materially diminish the nuisance of mosquitoes, and under favourable circumstances to practically extirpate them; though, in a usual way, complete success must not be expected. In the exceptional cases where this is possible, there is, of course, no need for the adoption of any other sort of measures; but, in the majority of cases, an amelioration only in the numbers of insects is all that can be attained; and it is necessary to guard against the risk of some of the survivors becoming infected, by the adoption of measures of the second and third classes. Of these the second, _i.e._, the protection of man from mosquito bites, is in most cases the most easily practicable.

A variety of ointments and applications of various sorts have been from time to time vaunted as protectives, and the presence of certain plants, such as the eucalyptus and the castor-oil shrub, have also been stated to be so obnoxious to mosquitoes of all sorts that they might be trusted to make themselves scarce wherever these plants might be found. For these ideas there is doubtless this much foundation in fact, that most strongly smelling bodies really are obnoxious to mosquitoes; but unfortunately, whatever objection they may have to strong scent is not very deeply rooted, and in default of more congenial shelter they will settle upon either eucalyptus or castor-oil plants, and will brave even the hated smell of paraffin to secure a good feed on the blood of a human or animal subject. All these special applications to the skin, too, have the further disadvantage that, though some of them are fairly effectual for a few minutes after they have been just applied, and so enable the user to get sleep, they leave those who are deluded into depending upon them to fall unresisting victims, as soon as the thick of the scent has evaporated. So that, though valuable for securing rest, they are worse than useless from the point of view of the prevention of malaria. With these untrustworthy exceptions, all available measures are of a mechanical character, and consist in modifications of our housing and clothing.

It must be remembered that during the working hours of the day there is little chance of being attacked, at any rate in the open air, and the same is the case in well-lighted rooms. Thus men whose work takes them into the open air for some considerable portion of the day, or are occupied in well-lighted offices, run much less risk than ladies, who, when they attempt to face the hot weather at all, are too fond of shutting themselves up in a darkened room, devoid of light or fresh air, and filled up with hangings and other superfluities, so as to form a perfect mosquito paradise in which the insects can fly about and bite during the day as comfortably as during the night. With such exceptions, there is therefore no need to modify costume to diminish the chance of mosquito bites as long as the sun is up, or even during the twilight, as long as one is in motion. It is when people are resting after the evening game of golf, racquets, or tennis, that they are most commonly attacked while awake; but the time of greatest danger is the period passed in sleep. During the waking hours it is uncommon for a mosquito to get the chance of an undisturbed meal by attacking the face and hands, but she often does so by attacking the ankles, and even thick stockings are no adequate protection. Trousers are therefore more suitable than knickerbockers for evening wear, and should be made extra long; so that when turned down after taking one’s evening exercise, they thoroughly protect this very vulnerable portion of the person. A lady can generally arrange her dress so as to protect herself, but the ordinary costume of children is extremely dangerous, and certainly should be modified to meet this danger during the hours when mosquitoes are active. In the case of little boys a “sailor suit” with long voluminous trousers meets the difficulty; and--fashion or no fashion--it is a clear duty on the part of mothers to devise some cool but adequate protection for the little girls. The alternative lies between doing so and wilfully offering them as sacrifices to the god of dress by needlessly exposing them to the danger of infection.

The low-necked, sleeveless dresses worn by ladies in the evening must, we can well understand, be very temptingly cool wear in the climates with which we are dealing, but are obviously extremely dangerous, as they leave a large surface of the person exposed at the very time when mosquitoes are most active. A dress covering these parts should be therefore substituted, which, however, may safely be made of the lightest materials, provided that it be so puffed or otherwise “confectioned” as to make it difficult for a mosquito to get within reach of the skin. Mosquitoes are always fond of collecting under tables, as they are there sheltered from the glare of the lamps, and on this account it is advisable for men to wear straps to their trousers when dressing for dinner; and though the plan is a very old-fashioned one, I have some hope that the suggestion may meet the approval of our better halves, as, whatever its real object, the adoption of the plan certainly gives the wearer the air of having sacrificed comfort to appearances.

There would, however, be no need of modifying costume for indoor wear in any way were houses properly protected against the entrance of mosquitoes by means of suitably planned wire-gauze protection to all openings.

The plan in question was devised by Professor A. Celli, the Principal of the Institute of Hygiene in the University of Rome, and in Italy at least has long passed its experimental stage; though, owing probably to the small number of Englishmen who are familiar with the Italian language, it appears to be practically ignored even by our specialists on the subject.

Within a few miles of the great city of Rome there are large areas where malaria, far more virulent than the type of disease we usually meet with in India, is so rife that, during the malarious months, the country is practically deserted by all but a few necessary railway officials and caretakers. Amongst the former the mortality and invaliding used to be so heavy that the working of the lines was a matter of the greatest difficulty.

The majority of the peasantry, being only temporary inhabitants, live in grass huts not a whit in advance of those of the savages of Central Africa, and from the migratory nature of their employment, are among the most ignorant and backward of the Italian populace, and so about the last people likely to lend themselves to the adoption of any “new-fangled” custom. As a matter of fact, however, the object lesson of the advantages of the system have been so obvious that, after the first year, there has been no difficulty in securing the eager co-operation of the simple railway men and scarce civilised farm hands. As the system is necessarily being very gradually introduced, there are plenty of unprotected houses for comparison, and after personally conversing with the inhabitants, the writer found that all who had enjoyed the benefits of the plan were convinced of its efficacy.

It must be remembered, however, that it has been long a matter of popular belief in the Campagna that malaria was, in some way, caused by mosquitoes; and it is the difficulty of convincing those in high authority of this fundamental fact that is at the root of the indifference and inertia which oppose all attempts at amelioration in India and in many of our colonies.

During the first two years’ experiments on the Campagna, out of 25 protected cottages, with a population of 173 persons, only 8 persons contracted malarial fever; while in 30 unprotected cottages, having a population of 220, only 17 escaped the disease; although the protected and unprotected cottages were, as far as possible, paired as regards the site, and were otherwise of a uniform plan of construction, and all inhabited by the same class of railway subordinates.

The system is the one above all others most suited for adoption by private persons, because it secures an almost complete immunity in spite of the most unfavourable surroundings, and renders the user quite independent of the sanitary lapses of his neighbours; but in spite of this, the plan is almost ignored in our English colonies and dependencies, though the writer has recently received an interesting communication from a medical man practising in China who has adopted it with signal success.

Professor Celli’s plan consists in rendering habitations impervious to the entry of insects by closing all openings with wire gauze (mesh of about 12 strands to the inch). All windows, as well as such doors as only serve as such, and are not absolutely required for ingress and exit, are permanently closed by frames covered with the gauze, and all indispensable exterior doors are fitted with _double_ spring doors of the same material, sufficiently separated from each other to secure the closure of the first door before the second can be opened.

In most Tropical residences, the number of doors is far in excess of actual needs, it being nothing uncommon to find rooms with four or five doors, all opening in the exterior. Though desirable and even necessary for free ventilation, no room can possibly require more than a single door opening on the outside, and in a well-planned house with suitable corridors, there is no real necessity for more than one or two exterior doors to the whole house. All outside doors, then, not absolutely necessary as such, should be treated as windows and permanently closed with single frames of wire gauze, so that the number of the more expensive double spring doors may be reduced to a minimum. In Tropical climates it is, however, essential that a considerable area of verandah should be included within the protected area, as a good deal of time is necessarily most pleasantly spent in the verandah, not only in the evening, but during the rains throughout the whole day. On this account a northern verandah should be the one selected for protection in this way.

The main obstacle to the adoption of the plan is undoubtedly the expense, which would amount to £20 or £30 for an ordinary Indian bungalow, and though this may appear by no means prohibitory in the case of permanent residents, it puts the matter practically out of the reach of even well-paid officials, as they can never count on enjoying the benefits of any permanent improvement of this sort for more than a few months; the wisdom of our rulers almost always leading them to transfer an officer to another station long before he is likely to have thoroughly learned his way about the streets of the town he has to govern.

On the preceding page is given the ground plan of an actually existing “up-country” bungalow of a very usual type in which the spaces guarded by gauze are indicated with dotted lines. The original doors are shown as complete, and the windows as shaded gaps. As will be seen, the number of doors for actual traffic is reduced to three, not counting those of the bath-rooms, which, being but little used during the hours of mosquito activity, have been left with single spring doors only.

There are many situations, such as houses necessarily placed in the midst of canal irrigation--Government canal bungalows for example--in which no other method of protection is in any way practicable, and it is clearly the duty of Government to protect officers, such as irrigation and forest officials, whose duties lead them into specially dangerous places, in this way in all cases where official quarters are provided. There cannot be the least doubt, too, that the capital so spent would be found to be a highly remunerative investment, and that this would be equally the case if steps were taken to protect all barracks in this way instead of wasting the costly soldier by needless invaliding. In the case however, of civil and military officers, who have to rent their houses from landlords, who are generally needy natives, with neither inclination, nor means, to provide costly improvements, the utmost they can do is to provide themselves with a sufficiency of portable folding gauze screens to protect their sleeping chambers. In any given locality there is generally some approach to a standard size for doors and windows, so that by the exercise of a little ingenuity it ought to be possible to adapt a set of folding screens to any room, allowing them when too large to overlap the sides of the embrasure, and supplementing deficiencies with sacking or rough planking. In India, for example, door openings are usually about 7 ft. by 4 ft., and screens opening out to this size might be utilised in most houses. It is obvious that the set of frames provided for each room must include one filled with a small spring door. I believe that a number of screens capable of opening out to something larger than the dimensions of an average doorway would be less bulky than any possible portable mosquito-proof room--and at any rate a complete set for an ordinary family would weigh far less than an average piano, and would be far more conducive to health. It should be added that in this, and in all cases where single rooms are placed under protection, all doors, internal as well as external, must be protected, and as they would in no way prevent the use of a punkah, they would be an enormous improvement on the ordinary mosquito net, which, failing such appliances, is an absolute essential to health during the malarious season.

Where nothing more permanent is possible, recourse must be had to mosquito nets, which can with care be made to afford a fairly thorough protection during the most dangerous portion of the twenty-four hours. It is a mistake, however, to trust to tucking the net in beneath the mattress, as this is apt to become disarranged during the night, and it is further very undesirable that the net should touch any portion of the mattress at all, as if it does so, the net can be also touched by the sleeper, who thus readily exposes himself to being bitten through the net. The top of the frame of the net should, therefore, be made both longer and wider than the bed and should be long enough to reach easily to the floor, with which its edge should be kept in contact by means of a hem weighted with sand or small shot.

I have seen, especially in Calcutta, several attempts at the construction of curtains so large as to admit of a punkah being swung inside them, the top of the curtains being carried right up to the ceiling, and the strap of the punkah being pulled through a sort of sleeve; but the arrangement is necessarily an expensive one, and the swing of the punkah is always more or less crippled by the sleeve. A better plan is, I think, to make the frame supporting the netting very low, scarcely higher in fact than that of a child’s cot, so that the punkah swinging outside, but almost in contact with it, still passes within a foot or two of the sleeper. Such an arrangement is rather awkward to get in and out of, but this drawback is a very trifling one, compared with the enormous advantage of combining the protection of the net with the comforts of a punkah. For this idea I am indebted to Mr. Symmonds, of Rosa, whose contrivance I presume it is, as I have certainly never seen beds fitted in this way in anyone else’s house. For sleeping out of doors in the open, the net must, however, be of the usual fashion; as if the wind be at all strong, a weighted hem would not suffice to keep the net closed. It is therefore important when sleeping out to use a large bed, so that contact with the net may be less likely to happen; and the top of the net should be formed of ordinary calico, so as to keep off the dew. Not unfrequently the mesh of the netting sold for making mosquito nets is too coarse, a point of some importance, as Anopheles mosquitoes in particular are adepts in creeping through small openings; and as the writer has found it impossible to confine them in enclosures formed of the coarser patterns of net, it may be concluded that such a material is equally inadequate to keep them out.

References to the protection against malaria afforded by mosquito nets by observant sportsmen and explorers are to be found in numbers of books of travel and adventure published long before any explanation of the fact was possible; and during the malarious season it is nothing better than culpable rashness to pass the night without this protection, except in a room properly guarded with wire netting. It is quite common to hear it asserted that a punkah alone is sufficient protection, but this is an entire mistake, as I have repeatedly watched a mosquito making a comfortable feed on my person within a few inches of a spot actually flicked by the towel which it is usual to pin on to the lower edge of the punkah. In non-malarious months, such as the hot dry weather preceding the rains in northern India, there is, of course, no need of a net except as a matter of protection against the harmless, but very annoying, Culices that are very common at that season of the year; and in spite of its inferior protection against being bitten, many will prefer the freer air current afforded by the punkah. After the commencement of the rains, however, the fact cannot be too strongly emphasised that to sleep without the protection of a net is to wilfully expose oneself to a real and ever-present danger.

In the matter of preventing mosquitoes from becoming infected it is obvious that comparatively little can be effected by the private individual. All he can do is to bear in mind that persons suffering from malaria are as great and real a danger to their neighbours as those affected with scarlet fever, small-pox or any other communicable malady, and accordingly to try to limit the number of such cases amongst his servants and dependents. In the great majority of cases in all probability, the mosquito that infects the European resident has been infected by a case amongst his servants; and quite apart from philanthropic considerations, it is most important to detect all such cases and have them treated with quinine.

It is a well-known fact that, even where the drug appears to fail to cure the disease, it is very difficult to find the malarial parasite in the blood of cases that have been well dosed with the drug, and as there must be parasites present in the blood itself in order to convey infection to the mosquito, it is obvious that, apart from its curative action, quinine may also be said to act as a disinfectant. On this account, where the removal of a servant “down with fever” cannot be arranged, it is highly important that he should be liberally dosed with quinine; and it must be remembered that it is not sufficient to supply him with the drug, but that it is also necessary to see it taken. In some countries, the native is so truly a child in intellect, that he has to be treated like one if a bitter drug is to be administered; while the Indian, though in no way wanting in intelligence, has often a prejudice against quinine owing to the active propaganda against the drug preached by the Baids and Haqims, or practitioners of the indigenous systems of medicine. As a matter of fact, I believe these men use quinine largely, but they take care not to let their patients know they are taking a drug which can be got for a halfpenny a full dose at any post office, and try to prevent the spoiling of their market by promulgating all sorts of fables as to its dangerous and harmful character.

According to the queer phraseology in vogue amongst these folks--and it is not so long ago since it was employed also in Europe--fever is a cold disease which by an attractive paradox should be treated by cold remedy, while quinine is made to belong to the opposite category of medicinal agents. It is as well, then, to be prepared for objections of this sort; but, as a rule, the personal influence of an European employer will suffice to secure the taking of the medicine, provided he will take the trouble to personally see it swallowed.

Liable as all residents in the Tropics are to be attacked with fever at times and places where skilled medical assistance is not obtainable, it may be well to conclude this chapter with a few words on the treatment of the malady. This really resolves itself into the adequate administration of quinine; for provided a sufficiency of the drug can be got into the circulation, it will, I believe, always cure malaria; but it is one thing to make the sick man swallow the drug and another to secure a sufficiency of it being absorbed into the blood; and unless this takes place, the remedy can have no more effect than as much oatmeal or any other inert substance. Anyone who has suffered from a severe attack of malaria, or had the nursing of a case, must have noticed that want of power to tolerate or digest even the lightest food, is one of its most prominent symptoms. In the more virulent type of the disease, nausea and vomiting is one of its most distressing features, and are nothing more than the outward manifestations of the fact that the digestive organs have ceased to perform their functions, and this may be equally the case, even where these additional evidences of the fact are not so prominent.

A little reflection will show that it is very unlikely that quinine or any other drug will be absorbed by a stomach that can no longer deal with even the lightest food, and hence it is not surprising that the severer forms of remittent fever will often resist quinine for long periods. For the same reason that quinine so often fails to do good in virulent cases, it is equally obvious that it is unlikely to do harm, and the absurd theory that “blackwater fever” is the outcome of treating malaria with quinine may now, I think, be said to be abandoned by all, save perhaps one or two of its original propounders; for though quinine appears to be of but little value in the treatment of that doubtfully malarial disease, it has now again and again been shown to occur in patients who have taken no quinine at all.

It cannot, therefore, be too strongly insisted upon that, in spite of failure to produce immediate effects, the administration of quinine should be steadily persisted in, as sooner or later in almost all cases a sufficiency will be absorbed to check the disease.

From what has been said, it is clearly important to do our best to put the digestive organs, if possible, in a position to perform their functions, and as in the majority of cases the sluggish bowels are loaded with half-digested or undigested food, it is a good general rule, as a preliminary to the administration of quinine, to administer some unirritating laxative, for which purpose nothing can be better than our old friend and bugbear of childhood, castor oil; and the dose should be repeated whenever constipation becomes a symptom in the course of the case. Once the laxative has acted, the sooner quinine is administered the better, and, unless the patient be one of those unfortunately constituted persons who are unable to take it--and there are some few to whom quinine seems as poisonous as it is to the malarial parasite--it should be given in full doses to the extent of 20 or even 30 grains (1 to 2 grammes of metric system) in the twenty-four hours. A dose of 10 grains, followed by others of 5 grains each, will usually be found a convenient plan of administration; but there are cases which do better with smaller doses more frequently administered. The best way to give it is, I think, to stir up the powder in a little milk; and it may be well here to offer a word of caution as to the employment of the drug in the form of tabuloids. For some reason, the drug appears difficult of digestion in this form, for I have repeatedly found fever yield at once to the ordinary powdered form of the drug, after days of fruitless treatment with quinine tabuloids obtained from firms of so high a reputation that the suggestion of the substitution of some less expensive material for quinine is quite untenable. The indiscriminate use, too, of antipyrin, phenacetin, &c., is also to be deprecated. They are all powerful depressants; and though they afford great relief to the aches and weariness of an attack of fever, undoubtedly have no effect whatever in curing the disease, even if they do not, as I have often been inclined to suspect, tend to prolong it. Where the suffering is very acute, an occasional dose may be of use for securing rest, but anything like continuous dosing with medicines of this sort should be carefully avoided. On the other hand, the old-fashioned “fever mixture,” composed of ten or fifteen drops of nitrous ether with a drachm of Minderus’ spirits (_liquor ammoniæ acetatis_), every four hours, in a wineglass of water, is often of great use in favouring perspiration, besides acting as a useful diuretic; and may be recommended as not only affording much relief to the patient’s subjective symptoms, but also of being absolutely safe even in inexperienced hands.

Except in the weakness of very prolonged attacks, stimulants should be but sparingly given, but they should not be withheld when the patient is flagging, and obviously falling into what is known as a “typhoid state.”

It is almost needless to remark that care is required in the matter of diet. During the febrile periods “slops” only should be given, and then in not too large quantities at a time; but in those cases where there is a distinct fever-free interval between the paroxysms of the disease, a great deal of license may be allowed, and solid food of a light digestible sort is often not only well tolerated, but even beneficial, while it is almost needless to say that these intervals of returned digestive power should always be seized upon to get a liberal supply of quinine into the system. During convalescence the administration of 10 to 15 grs. a day of quinine should be maintained for at least a week after the disappearance of all febrile symptoms, and some ordinary tonic, such as Easton’s syrup, is often useful in facilitating the return to strength.

The least sign of a relapse, as evidenced by a rise of temperature, of however temporary a character, should be met with a further treatment with quinine for at least a week or ten days, as it is a clear sign that the disease is scotched, but not killed, and that some of the parasites are still lingering, in a latent condition, within the system; for the patient cannot really be considered as cured till the last of these is put an end to.

The length to which this chapter has attained may be justified by the fact that the universality and the extent of the mischief wrought by malaria in tropical climates renders the subject by far the most important of all in connection with the preservation of health in the tropics; and the writer trusts his readers may be moved to do as much as they possibly may to preserve themselves and their neighbours from the havoc wrought by this insidious disease, for without an informed and intelligent public opinion to back them, no possible efforts on the part of sanitary officials and medical men can be expected to exercise any great or lasting effects on the prevalence of the disease.