British Malaya: malaria control in the Federated Malay States

3.1	Malaria Advisory Board, Federated Malay States

In September 1911 the Federated Malay States Federal Government decided to create an Advisory Board for the purpose of dealing with malaria in the Federated Malay States, and invited a few unofficials to become members. It was stated that “The Government has decided to appoint this Board because malaria has become more prevalent, and because it is felt the effectual and efficient control of the disease could be exercised better by a representative Board than by one Government Department.” The first members of the Board were, Sir E. L. Brockman, Chief Secretary, Federated Malay States (President); Dr C. L. Sansom, Principal Medical Officer, Federated Malay States; Dr A. T. Stanton, Bacteriologist, Institute for Medical Research ; Mr J. H. M. Robson, Member of the Federal Council; Mr F. D. Evans, Assistant Engineer, P.W.D.; Mr H. R. Quartley, Manager of Seafield Estate; and the writer.

Referring to the objects the Board had in view, Dr Samson writes in his Annual Report for 1911:

This Board intends

1. (1)To collect and distribute information regarding malaria;
2. (2)Advise how anti-malarial measures could be most advantageously carried out in each district;
3. (3)Encourage and advise local bodies in their efforts towards extermination of mosquitoes;
4. (4)Draw up appropriate legislative measures.

The dissemination of correct information is of no small importance; there exists in the minds of a great many people, a doubt whether the mosquito carries malaria or any other disease; until this heresy has been corrected it is obvious that in some places preventive measures will only be received in a half-hearted manner and carried out unintelligently. Then there is another group who are inclined to believe that as long as the special malaria carrier is exterminated, other species of mosquito can be allowed to breed with impunity, oblivious of the fact that all mosquitoes are an irritating nuisance, and their constant attacks do not improve health; and more than that, some of them inflict dengue, elephantiasis, and other objectionable ailments. One of the first steps taken by the Board was to begin to arrange for the instruction of all children in schools on the causation and prevention of disease, and that also warning and advice shall be brought to the constant notice of practically all adults. It is felt that systematic diffusion of knowledge regarding this enemy of man, its habits, the harm it does, and how to exterminate it, will not only encourage the individual to do his share, but also facilitate the efforts of local bodies and probably make them more effectual.

One most important detail connected with anti-malarial work is continuity of policy, of supervision, and subsequent upkeep. It is extremely unsatisfactory if a succession of men are made responsible for the carrying out of one particular piece of work, and changes are to a certain extent inevitable; but with a Central Board, having a settled policy, advising procedure and watching results, not only will preventive measures be more complete, but mistakes obviated. Anti-malarial drainage is not worth undertaking unless it is done very thoroughly—a small spring in a ravine overlooked, will mar the effect of an otherwise complete system.

The remaining objectives of the Board do not require enlarging upon, except that it was decided to carry out a scheme of anti-malarial drainage in a selected area which could be tested, and, if found successful, be used as a model scheme for other similar places. Early in 1911 the Liverpool School of Tropical Medicine published a book entitled The Prevention of Malaria in the Federated Malay States, by Dr Malcolm Watson, which contains a valuable record of successful work accomplished by the author, as well as a description of a method of dealing with ravine streams in hilly country, which is nearly always intensely malarious after being opened up.

On two rubber estates in the Batu Tiga district—Glen Marie and Seafield—a thorough system of underground draining has been carried out. The underlying principle was, that springs and streams being favourite breeding places of a very dangerous mosquito, these springs and streams must be conveyed underground, and then the insect will be exterminated. On a larger estate such drainage of all streams would be too costly, so Dr Watson decided to render a certain area completely dry, and place all the inhabitants in the centre of this area.

The next step was to decide upon the method of drainage. Even in a selected area the Panama system was shown to be almost prohibitive, as material would have to be carted very long distances at great expense. So an ingenious idea has been adopted of laying ordinary rough, agricultural pipes along the course of streams, and tapping springs, these pipes carrying all the daily flow; then in order to accommodate the occasional tremendous rush of stormwater, open ditches are made of considerable width, so that scouring is prevented and a storm flow only allowed to develop a depth of a few inches. The method is simple and extremely economical, and if efficiently carried out should prove successful. That pipes get choked occasionally, and from time to time some of them get washed out in exceptionally heavy storms, goes without saying, but replacement is only a matter of a few hours’ work and insignificant expense, so that accidents of this sort need not cause anxiety, and it has to be borne in mind that the most expensive drainage pipes and culverts laid with elaborate precautions do not escape destruction by storms.

These experiments are being watched with great interest; they are being carried out by a man of experience, who has studied the subject for some years, and there is every prospect of success. When the system has been thoroughly tested and found good, then every district and estate in hilly country will be able to deal with their ravine streams economically, and both will reap very great benefit. Dr Watson has been kind enough to inform me that the results are encouraging; the figures will be published later on when sufficient time has elapsed.

It appeared to me that the most urgent work before the Board was that of clearing malaria out of Kuala Lumpur, the federal capital. Something like $47,000 had been spent between 1908 and 1911 with this object in view, but without any improvement to the health of the community; for the proper method of dealing with ravine Anopheles had not then been studied, and was not available for those actually in charge of the work. I suggested that the Board should undertake anti-malaria drainage in Kuala Lumpur on the method employed on Seafield and Glen Marie estates. The Board approved of this proposal, and Mr Evans, as their engineer, has carried out the work with great care and intelligence. From time to time I have inspected the areas drained, and have found that within twelve hours after heavy rain no water can be found in the ravines.

It is difficult to obtain statistics of the benefit of this drainage; most of it has been carried out in the official residential area. It may be said, however, that malaria is now almost unknown in houses where formerly it was hardly ever absent, and as the Annual Report puts it,4

Amongst the Government officers and their servants who live in the drained area to the west of the railway, practically no cases of malaria have occurred. This is very satisfactory, as the officers and their servants living in this area were repeatedly attacked previous to 1912, when some of the bungalows lay empty at times, because officers preferred not to live in them, despite a shortage of bungalow accommodation.

Definite figures have, however, been obtained regarding the health of the police force, and in the Annual Report it is said that:

The average monthly percentages of cases of malaria treated in hospital or given sick leave were 35.75 percent, in 1910, 57.01 percent in 1911, 27.33 percent in 1912, and 11.3 percent in 1913. … These figures mean that in 1911, to take the worst case, every Indian at the depot was in hospital or given sick leave for malaria on an average seven times in the year. … It may be mentioned that the improvement was obtained notwithstanding the large increase in density of the population at the depot subsequent to 1911, when in consequence a large number of the men were without the protection of a mosquito net at night. Quinine has only been given to the men under hospital treatment, or to those who come to ask for it.

3.2	The Anti-malaria Committee of the Straits Settlements

In many parts of the colony of the Straits Settlements, which with the Malay States forms what is often conveniently called British Malaya, and with them forms a geographical unit, malaria has been as severe as in the Malay States; and in June 1911 an Anti-malaria Committee was created in the colony, with the same objects as the Malaria Advisory Board of the Federated Malay States. Curiously enough, just as the most urgent problem in the Malay States was the severe malaria in Kuala Lumpur, the federal capital, so in the colony, it was the health, or rather ill-health, of the city of Singapore, the capital of the colony, which called most urgently for attention. For many years it had been the subject of careful consideration; indeed, some years ago, Professor W. G. Simpson was commissioned to make a special inquiry into the high death rate. In addition to his other recommendations, he advised that drainage of certain portions of the town should be carried out, as had been done in Klang and Port Swettenham. The town had a good water supply, an efficient scavenging system, and a well-equipped sanitary department, and is, in my opinion, one of the best-managed and cleanest large towns in the East.

In spite of everything which could be done, the death rate from malaria was very high; and its effect on the general death rate was so serious, that in the months of May and June 1911 the male mortality rates reached 86.2 and 92.3 per 1000, and the mortality rate for the whole population, exclusive of cholera and smallpox, for June was 81.5. The problem was complicated by the fact that considerable numbers of Chinese were known to come from outside to Singapore when ill, and often died there. In an able report Dr Middleton dealt with the subject of malaria in Singapore, the methods which had been adopted elsewhere, and urged that “a comprehensive and well-considered plan of campaign should therefore be prepared and steadily persevered with, adequate annual appropriations being made for this purpose, both by Government and the Municipality.” On his suggestion, I was invited by the Anti-malaria Committee to visit Singapore and advise what should be done in an area which had been selected because it was “known to be malarious, and is not large enough to make supervision difficult.”

I did so, and in cooperation with Dr Middleton, Dr Finlayson, and Mr Ball, the acting municipal engineer, drew up a scheme which dealt with every Anopheline breeding place in an area 2 miles long and half a mile wide in the Telok Blanga district, where the harbour is. A house-to-house visit was made, and the number of children with enlarged spleens was recorded. Dr Middleton, Dr Finlayson, and Mr Ball also visited me at Klang, and I had the opportunity of showing them what had been done there. I made a special point of showing our mistakes, so that they might be avoided in Singapore.

It is too soon to say much of what results have been attained in Singapore. I may say, however, that the work has been admirably done in both Telok Blanga and other districts; and having a thorough grasp of the essentials, the conductors of the experiment have avoided the usual pitfalls.

It would be premature to assert that Singapore has been made healthy; but Dr Middleton was able to record that the death rate, 34.12 for 1913, was “the lowest for nineteen years,” and that it “is 7.98 per 1000 below the average annual death rate for the last twenty years.” Of even more significance is the alteration in the spleen rate. In 1911 it was 50. Dr Middleton now writes in his report: “Dr Finlayson has found that the spleen rate amongst children at the schools in the Telok Blanga district progressively decreased till ultimately it reached zero, and it is to be hoped that this is an indication that the measures taken will not prove without effect.”

If the lower death rate is really due to the reduction in the amount of malaria, it means a saving of fully 2000 lives per annum, as well as the prevention of an enormous amount of sickness; for Singapore is a city with a population of nearly 275,000 people.

3.3	Rice Fields and Malaria

That the formation of rice swamps led to the production of malaria is an old observation, and the attitude of the medical profession has been, very naturally, to view them with great suspicion, and to advise their prohibition within a mile of a town. From my observations on the peculiar habits of our Anopheles, the idea occurred to me in 1909 that by converting ravines into rice swamps with putrid vegetation, it would be possible to drive out the dangerous Anopheles which live in pure water, and, with them, malaria, without having to spend large sums on subsoil drainage. To determine if this was possible, I examined a large irrigation at Krian, in the State of Perak, and found it to be practically free from malaria. Of 718 children examined by Dr Delemege and myself, only 20 or 2.7 percent, had enlarged spleens. There were, moreover, no less than four species of Anopheles present, but the absence of malaria only served as proof of what we already knew, that these species take no serious part in the transmission of malaria. The Krian irrigation area is 66,000 acres in extent. It draws the water supply from a large reservoir made by damming up two considerable rivers. In the reservoir the jungle trees have gradually died out, and the water has a somewhat brownish peaty colour, much like that in the savannahs behind the sugar estates in British Guiana.

A little farther south there are a series of rice fields in Bukit Gantang valley: they are irrigated by water coming directly from the hills; not having been stored in a reservoir, it is purer than that of the Krian rice fields. In this valley I found severe malaria among the children, the spleen rate varying in different schools from 43 to 61; and in addition to the four species of Anopheles found at Krian there were three others, one or all of which presumably must carry malaria. As a matter of fact, I had already found one to be a carrier in nature, and subsequently Dr Stanton showed that another (A. albirostris) is also culpable. In the hill streams at the sides of the valley, A. maculatus was discovered in abundance, but in the rice fields it was never found. Table 3.1 shows clearly the results of the investigation.

Although I was unable to utilise the information I had now gained for the purpose of clearing malaria from the ravines of hill estates, the investigation showed that rice fields may be free from malaria; and from these and allied observations I suggested that, in the future, it might be possible to eradicate malaria from certain places by altering the composition of the water in such a way as to make it uninhabitable for some particular malaria-carrying mosquito. It was, therefore, with the greatest interest that I found in 1913 that one of the most dangerous malaria-carrying Anopheles which exists had been driven from the rice fields of British Guiana by controlling the water supply (see Section 17.8). This is one step more towards what I suggested in 1910, in a public lecture given in Kuala Lumpur, in the following words:5

But when we came to work out the Anophelines, it was found that different species were found in the middle of the swamp from those on the hills. Nature has, therefore, carried out a great experiment. There were three groups of Anophelines: one on the hills, one on the rice fields close to the hills, and a third lot in Krian, far from the hills. Now why do these vary? Clearly on account of something in the water; and it can easily be imagined that only a small change would assimilate the Bukit Gantang water to that of the Krian rice fields, and then malaria would disappear from Bukit Gantang too. I believe that in this way a great anti-malaria method will be evolved, and I can look to the time when we will be able to play with species of Anopheles, say to some ‘Go’ and to others ‘Come,’ and to abolish malaria with great ease, perhaps at hardly any expense. Drainage schemes may become things of the past, and future generations may smile to think of how their ancestors, who thought they were so clever, burned the house to cook the pig.

A solution of the problem of hill-land malaria on biological lines has been steadily sought for, and when Dr Strickland was appointed as travelling entomologist, I suggested the following as his course of study:

1. (1)Healthy, flat land (coastal belt);
2. (2)healthy wet land (Krian rice fields); and
3. (3)then working up from the coast into the valleys of Negri Sembilan, from what I believe healthy into what is unhealthy.

There is much to be learned here, I’m sure, for the undrained swamps in valleys are certainly in many places healthier than those which are clean-weeded. Why this should be is clearly an important question. … The above seems to me the main line of research he should pursue.

3.4	Water supplies in the Federated Malay States

Almost all the towns in the Federated Malay States have good water supplies, usually obtained by impounding streams in the jungle. But in rural districts water is obtained only from surface wells, which are very liable to pollution. With the rapid increase in the population on estates, the danger of disaster from cholera became greater each year, while, subsequent to improved drainage, the supply of water from the wells on the coast land became less and less.

3.5	Rules for Sanitation on Estates

Such rules were drawn up a few years ago. On some estates these rules are strictly enforced by managers; on others there is much room for improvement. They were as follows:

Rules for Estate Sanitation

Prepared by Dr Malcolm Watson and approved by the Principal Medical Officer of the Federated Malay States, by the Planters’ Association of Malaya, and by the Council of the Rubber Growers’ Association (Incorporated).

It has been established beyond doubt that the most troublesome mosquitoes breed mainly in stagnant water in tins and other receptacles. Such mosquitoes, although they do not carry malaria, carry other diseases, such as elephantiasis (filaria), and are thus a danger as well as a discomfort. For this reason all receptacles capable of holding water should be buried as stated in the rules.

The Federated Malay States estates are at present almost entirely free from cholera and typhoid (or enteric) fever and plague, but the rapidly growing population greatly increases the risk of these diseases becoming established. Pure water supplies, clean dwellings, and clean surroundings will prevent these diseases, which are a danger to European and native alike. Attention to the following rules by the managers of estates is, therefore, a duty to themselves, to their labourers, to their estates, and to the community.

Wells Drinking—Bathing

1. (1)When drinking water is procured from wells, such wells should not be dug within a distance of 100 ft. from the coolie lines, residences, latrines, or washing places.
2. (2)These wells should be separated from coolie lines, residences, latrines, and washing-places, by a drain dug (not less than 15 ft. away from the well) as deep as the estate drains in the vicinity, and called the intercepting drain.
3. (3)Wells should be provided with a pump placed at least 15 ft. from the well. When possible, it is preferable to place the pump on the opposite side of the intercepting drain from the well.
4. (4)Waste water from the pump should be collected and led to the intercepting drain. This is best effected by a small apron of ferro concrete, 3 ft. square, below the pump, draining into half channel pipes leading to the intercepting drain. Should it be necessary to discontinue the use of a well, the pump, apron, and half channel pipes can easily be removed and fitted up at the new well.
5. (5)Wells must be fenced so that no one can walk within 15 ft. of them; nor should it be possible for coolies to dip buckets into them.

On Hill Land

The head of a ravine should be reserved for the water supply. The head of the ravine should be fenced in. These precautions will ensure that no pollution can be washed into the well.

Well Water Dangerous

Shallow or surface wells are those above the first impervious stratum, which may be 100 ft. below the surface of the ground. Such wells are the most dangerous possible water supply. They are liable to gross pollution in three ways. (1)Contaminated buckets may be dipped into them. (2)Water polluted by clothing, washing, and bathing may run back into them. (3)Underground water passages, which are often very abundant, may bring pollution from a considerable distance, both in wet and in dry weather.

A large labour force should not depend on surface wells if a safer supply can be obtained. On hill land, permanent safe water supplies can be got from unopened ravines.

Scavenging

1. (1)A distance of 200 ft. around lines should be marked out by white posts.
2. (2)No empty bottles, tins, or any other rubbish should be deposited or buried within this area.
3. (3)All rubbish and refuse should be buried daily by the sweepers. Dustbins should be provided.

Latrines and Night Soil

1. (1)Latrines should not be situated within 100 ft. of lines unless there is a waterborne system of sewage.
2. (2)If trenches or pits are used, lime or earth should be applied twice daily in sufficient quantity to prevent nuisance, and completely cover excreta.
3. (3)Any night soil deposited elsewhere than in a latrine and near to the lines should be buried by a sweeper.

Night soil often contains the germs of cholera, typhoid fever, dysentery, and diarrhea. Flies, fowls, and dogs may spread these diseases if night soil is exposed on the ground.

Sweepers

There should not be less than one sweeper to three sets of lines.

Drains

1. (1)Brick drains simply pointed with cement are difficult to clean. It is much better to render the drain with cement, or use an earthenware half channel pipe.
2. (2)The end of the drain should be carried at least 15 ft. from the lines, and if possible should discharge into an estate drain.
3. (3)The sweepings of the drain should not be allowed to lie at the end of the drain, but should be buried daily when the drain is swept.
4. (4)Where soil becomes polluted and filthy at the end of a drain, ashes from the coolies’ fires should be applied.

Lines

Provision for cooking without exposure to rain should be made by (1)raising the lines 6 ft. from the ground, or (2)having a 10-ft. verandah, or (3)by kitchen in front of the lines.

If there is only a 6-ft. verandah in which to cook, the coolie must close it to protect himself from the weather. When verandahs are shut up, the rooms become dark. Darkness leads to dirt.

Clothing and food become polluted in dirty places, and then dysentery, diarrhea, and other diseases occur.

Lines should be lime-washed every three months, both inside and outside, especially inside.

Managers should keep a watch over the food supplies of a labour force. Underfed coolies are certain to fall an easy prey to malaria or any other prevailing disease. A well-nourished gang of men are frequently seen to be healthy when others in the near neighbourhood are attacked with illness.

Inspection of Lines

Lines should be inspected daily by a European or other responsible member of the staff in addition to being visited by a dresser. Coolies not at work or complaining of sickness can then be seen and sent to hospital if necessary.

3.6

Beri-Beri

Ten years ago the origin of the disease was admittedly an unsolved problem,6 of which, moreover, all the possible solutions seemed to have been definitely disproved. In particular it was held by those of most authority in tropical diseases, that the cause to which it is now correctly attributed had been put, by the very definite and categorical evidence of direct experiment, entirely out of court. But truth is hard to strangle, and today the result is accepted, that a malady which appeared to have all the marks of an infection, which produced devastating epidemics, more destructive because more persistent even than the plague, is due to nothing more than an apparently insignificant error of diet. To those who know how, like a pestilence, beri-beri disabled, and by its ravages even exterminated whole communities, it must rightly appear one of the most remarkable and beneficent triumphs of medicine that its onset may be prevented and its damages repaired by nothing more recondite than the change of one solitary article of food, in fact by the mere substitution of one commercial variety of rice for another.

How the truth [about beri-beri] was discovered is one of the most fascinating stories in medicine, and if I give only a short account of it here, it is only because even the briefest account cannot rob it of its interest and the lesson it contains.

In 1890 Eijkman discovered that fowls suffered from a disease very similar to beri-beri if fed on a rice from which the pericarp had been removed, and that restoration of the same pericarp cured them. This led to an important commission of inquiry, presided over by Vorderman in 1898, which produced ample evidence to show that the incidence of the disease did vary with the sort of rice used; but effect was denied the result, owing to Vorderman’s conclusion that the facts did not explain “the infectiousness of the disorder.” No incontrovertible evidence of the dependence of human beri-beri on any specific difference in food had been produced, and “with the rising tide of bacteriology all interest in this side of the question seems to have become lost,7 and the valuable results of Eijkman in particular became for a time submerged.” But “the claims of almost innumerable bacteriologists, from Pekelharing and Winkler down to Hamilton Wright and Dangerfield, to have isolated an infective causal microbe, may be dismissed as one and all inglorious failures.”

In 1893 Braddon noted “the peculiar exemption of the natives of Southern India (Tamil coolies) from beri-beri when immigrant into the very worst foci of beri-beri in the Malay States,” while “their sickness rate from all other causes exceeded that of all the other classes of natives beside whom they lived, and with whom they were equally exposed to the incidence of all supportable infective agencies.” At that time Braddon had no knowledge of Eijkman’s observations, and was influenced by the current views which entirely discredited the idea that there could be any connection between rice and beri-beri. Gradually, however, the evidence accumulated to show that there was a definite connection between the two; and in 1901 he submitted evidence to a Congress of Medical Officers of the Federated Malay States strongly indicating that the freedom of the Tamils from beri-beri was due to their use of a particular kind of rice, which he called “cured” rice. This paper and a subsequent one produced the hot controversy without which progress towards the truth would be much slower than it is; and in 1904 Braddon was in a position to publish a large volume of evidence in favour of his rice theory, and to show that all the observations brought forward by his opponents fell into line with his own theory. But for the controversy many of these observations would never have been made; having been made, they helped to establish the truth.

In the face of all the facts now showing a connection between rice and beri-beri, medical opinion in the Federated Malay States had to be revised; and Government gave facilities for Braddon, in association with Drs Fraser and Stanton, to conduct an important experiment on free Javanese coolies, who were engaged in road construction. The result was a further striking proof of Braddon’s theory that cured rice with the pericarp was a preventive of beri-beri, and a cure for the disease, if not present in too advanced a stage. For all practical purposes the cause of beri-beri was known; we had also learned how it could be completely prevented. There remained still to be discovered what was the exact substance in the pericarp which meant so much to the rice eater. In their laboratory, Fraser and Stanton, by experimenting on fowls as Eijkman had done, established the fact that a dangerous rice might be known by the small percentage of phosphorus pentoxide it contained; but they also pointed out that the phosphorus was not the important substance; it was only an indicator. The exact substance they have been unable to isolate; nor have any others [been able to do so]: it seems to be closely allied in chemical composition to—the will-o’-the-wisp.

One would have thought that the stamping out of beri-beri was now quite a simple task: if the dangerous rice were stopped, the disease must disappear. But unfortunately the dangerous rice is white in colour, whereas rice with its pericarp is brownish or red; and as the Chinese have learned to associate whiteness with purity, the sudden stoppage of the dangerous rice would lead to civil strife. Many suggestions to overcome the difficulty have been made; but it appears to me that, by the use of Fraser and Stanton’s indicator, the way out of the difficulty will be found. I suggest that gradually, and over a long period of years, the standard of phosphorus in white rice demanded by Government be raised each year or each two years; the Government should notify to millers and importers that, before rice manufactured in the country or imported can be sold, it must contain a certain percentage of phosphorus. In this way the change would come about so slowly that no one would notice it; unconsciously the people would be educated, and a new generation would arise that knew not the dangerous beri-beri rice.