LADY ANOPHELES
E. Douglas Hume
I hold no brief for the mosquito. She has always treated me as a mere restaurant, and I have provided her with so many meals that I feel all obligations to be already on her side. Also, her extreme talkativeness is almost as objectionable as her voracious appetite. Any one who has been kept awake by her buzz-z-z, buzz-z-z, buzz-z-z, on a tropical night must have come to the conclusion that “good will to all men” can never be strained to include good will to all insects. Moreover, the fact that the lady of the species alone feasts upon blood seems a reflection on the female sex. Yet, so it is: her husband is a harmless vegetarian.
All the same, when a sense of justice is strong, one does resent the misdemeanors of man being laid at the door of even the most exasperating insect. Certainly the sturdiest viewpoint of disease is to regard it as the outcome of inattention, personal or general, to one or other of nature’s observances. Instead, nowadays, parasitic organisms are blamed for most of the aches and pains of humanity, while their distributors are searched for in the realm of insects and animals. The mosquito has, perhaps, fallen a prey to her own weakness. Had she talked less, it is possible that she might have evaded her doubtful celebrity. As it is, she stands accused of being concerned with a no less formidable array of maladies than elephantiasis, yellow fever, dengue, and malaria.
Let us here concern ourselves with the last-mentioned, and the hungry suspect, whose name has been coupled with the disease, her Ladyship Anopheles.
She may at once be singled out from her fellows by her habit of discreet silence and her odd proclivity for standing on her head when resting and feeding. Other mosquitoes remain on all fours, or rather, all sixes, when dining. This acrobatic insect is, as everyone knows, accused of inoculating her human prey with a protozoon, or microscopic animal organism, which in its turn is held responsible for the heats and chills, the aches, the pains, the languor, all the miseries of malaria. The idea is a simple one,
requiring little intelligence to be understood. Is it rude to ask, what wonder that it has become popular? Less marvel, too, when one reflects that the theory is safeguarded by dividing Anophelines into a variety of groups, and claiming that the guilty must be the right sort, and yet further, the right sort duly infected.
Now, the means of infection must come about through the insect having feasted on a malarial subject. That its subsequent bite might poison the healthy sounds a contingent by no means unlikely. The drawback to this probability is that the mosquito possesses the feminine characteristic of fastidiousness. Malarial subjects are the very ones avoided by her hungry Ladyship. Here I may interject that I am not writing of insects under control. What a famished mosquito may or may not eat during the course of an experiment, I am not concerned with. I refer to mosquitoes in a natural state, and personal experience has made me observe that the one benefit of malaria consists in the freedom it confers from mosquito bites. Though these insects are in the habit of treating me as a very Ritz or a Carlton among restaurants, periods of malaria always freed me from their ravages. They like their food to be of the best, and the blood freest from fever is the provender for their delectation. During nineteen years of tropical life, my mother never experienced a single attack of malaria; yet she was always the chief pièce de résistance for every mosquito within her vicinity. It may be noticed that the individuals least susceptible to malaria are those most feasted upon by mosquitoes, including the suspects, though whether these be Anopheles Umbrosus, Anopheles Maculatus, Anopheles Christophersi, Anopheles Albimanus, Anopheles Argyritarsis, or any others of high-sounding title, I should certainly not presume to discriminate.
Why should this general evidence count for less than the few experimental cases upon which the mosquito theory is built up? These latter are mostly conspicuous by their weakness. Take, for example, the mosquito-proof hut placed at Ostia, and inhabited for three months by Dr. Sambon, Dr. Low, Mr. Terzi, and their servants. What analogy does this well-ventilated erection, raised above the soil, bear to many of the insanitary homesteads
of the Campagna? What analogy is there between its healthy inhabitants, further fortified by zest for a theory in dire need of proof, and the permanent dwellers in those unpropitious surroundings? If we admit strength in the case of the infected mosquitoes sent to the London Tropical School, whose stings are said to have produced attacks of fever in the late Dr. Thurburn Manson and Mr. George Warren, we must also remember that Abele Sola in the Santo Spirito Hospital in Rome, according to the account quoted by Herms in his Malaria: Cause and Control, is claimed to have fallen a victim to this disease from the bites of mosquitoes that had developed from larvæ in his own room, and therefore could not be reckoned as infected. Moreover, they numbered hardly any Anophelines, and of the very few present, it was not known whether any stung the patient. Yet, according to the modern theory, Anophelines alone could have been responsible for the mischief. The proverbial grain of salt seems a necessary condiment for the cases of experimenters.
In the short space at our disposal, we are not concerning ourselves with the micro-organism, first discovered in Algiers by Dr. Laveran, and considered to be the parasite of malaria. Without in the least committing oneself to a general belief in the germ-theory of disease, there may, here and there, be maladies produced by parasites. Yet, apparently, fever, bearing all the clinical symptoms of malaria, may occur without the presence in the blood of such organisms, no matter whether parasitic or inbred. On page 8 of the Medical Report of the Federated Malay States’ Government reference is made to an unusual swarm of sandflies, and the following commentary is given. “Whether sandfly fever exists we are not prepared to say, but many cases with all the clinical symptoms were noted and no malarial parasite was detected on blood examination.” Hence the sandflies come under suspicion! Might not another moral be drawn, and that is that fever may be due to causes less crude than the inoculation of parasites by objectionable insects?
The conditions that produce mosquitoes seem to be the same as the conditions that produce malaria, and, in any case, it is these that must be attacked, no matter whether Lady Anopheles be proved innocent or in any measure guilty. The mysteries that
surround the subject, the occasional outbursts of disease when areas have been drained, the usual method of improvement, the occasional betterment of health when the reverse process of flooding has taken place, may possibly be explained by the law of subsoil water. Dr. Charles Creighton writes in his History of Epidemics in Britain (p. 278): “According to that law, the dangerous products of fermentation arise from the soil when the pores of the ground are either getting filled with water after having been long filled with air, or are getting filled with air after having been long filled with water. It is the range of the fluctuation in the ground-water, either downwards or upwards, that determines the risk to health.”
However, far be it from me to descant upon the mysterious causes of malaria. My object is only to try to prove the unwisdom of rivetting attention upon the anopheline mosquito. Deductions as to her innocence may be drawn from the accusations endeavoring to prove her guilty. We are told how noticeable among troops the difference in fever rate has been between those that slept on shore and those that remained on board ship in malarious districts. But as the mosquito is free to come aboard too, how does that statement tell against her? I remember a host of such insect invaders on the Sydney, the French mail boat, when anchored at feverish Saigon. We carried a shipload away with us, and when out at sea they feasted on me to such an extent that I arrived at Singapore looking as though stricken with a rash, but otherwise none the worse for their greediness.
Again I was scarred for a long period after the venomous attacks of mosquitoes and sandflies combined at Kuala Klang, on the Malay coast, in its old days of fever, before it started a new sanitary career under the name of Port Swettenham. Yet these myriad bites produced fever of no sort, although I was at that time pronounced a malarial subject. I did not remain in Kuala Klang long enough to be affected by its unhealthiness; but, had Lady Anopheles been justly blamed, the terrible biting I underwent should have taken effect, irrespective of my removal. On the contrary, my own experience of fever was connected entirely with locality and never with mosquitoes. Intermittent fever, the genuine article, with its burnings, its icings, its whole programme
of miseries, had me constantly in its grip during residence at a particular house in Kuala Lumpur, the Capital of the Federated Malay States. My one compensation was freedom from mosquito bites. When I left that abode, fever left me, and soon after mosquitoes began to feed on me again with infinite relish. What matter? It was a proof of sound blood, freedom from that worse scourge, malaria!
To turn from the personal to what is far more important, the general, let us consider the Medical Reports from that haunt of malaria, the Malay Peninsula.
The year 1911 in the Federated Malay States held the unpleasant distinction of being particularly malarious. The mosquito theorists explained as cause a great influx of, often, unhealthy coolies from India, and much clearing of land, which distributed the mosquitoes, and drove them into the houses and among the inhabitants. But, if mosquitoes be culpable, why should this same year have also been particularly unhealthy in regard to most diseases, phthisis excepted? Yet the Medical Report for 1912 shows that, concomitantly with a fall in malaria, 1,010 fewer cases of dysentery were this year treated in hospital. There were 77 notified cases of smallpox, as against 286 in 1911; 29 cases of cholera, as against 620; and 5,676 cases of beri-beri, as against 6,402. The greater prevalence of disease in general in 1911 surely shows that the causes for its specific forms must be deeper seated than mere insect bites. Yet so dominating is the fashion to rivet attention on such factors as these that fundamental troubles, even when known, appear often to be unheeded.
The F. M. S. Medical Report for 1912 provides a good instance, taken from the portion dealing with the Institute for Medical Research, Kuala Lumpur.
On page 25 it states that the occurrence of several cases of bubonic plague in and near Kuala Lumpur rendered it advisable to consider the possibility of the disease appearing as an epidemic and measures to avert such a calamity. A short paragraph refers to reported cases of plague, and then follow nearly four pages devoted to rats. Toward the bottom of the fourth page come the pregnant words: “Nearly 50 per cent. of the plague-infected rats came from the small stretch of Ampang
Street, about 150 yards long.” The short description of this small area surely reveals a source of danger. “At the back of most of the houses there is a kitchen or bathing-place from which an open brick drain, covered with planks, runs through the house to the front of the shop and under the pavement of the five-foot way into one open drain at the side of the street. The plank covering of the house-drain is usually buried beneath sacks of grain or other heavy articles, so that the drain is not often cleaned. The open cement street-drain forms a convenient highway for rats, which can readily gain access to the house by the unprotected house-drains leading into it. Some eighty yards away the main drain empties into the Klang River, here a shallow and muddy stream with irregular, foul banks covered with reeds, rank grass and collections of garbage.” Now, who could expect rats to keep well in the vicinity of such a drain “not often cleaned,” and such a river, “shallow and muddy,” with “foul banks covered with collections of garbage”? Surely gratitude is due to the rodents, who, being nearer the level of the bad conditions, get ill first, and thus give human beings a fair warning of the sickness likely also to be their due, unless surroundings are made healthy for all animals, four-legged and two-legged. Yet, actually the Report has not a commentary upon these palpable ills, and, though it has by no means exhausted itself on the subject of rats, proceeds to vary the topic with fleas, the meteorological conditions that affect these high-jumpers, and the uses of guinea-pigs as flea-traps. The results of searching questions to medical men on the subject of flea bites are even given. “Of eighteen who replied one stated that he had never been bitten by a flea in his life” (p. 31). Most people must wish they were equally lucky. But not a single mention again of the uncleaned drains and the river choked with garbage during the course of pages all the more diverting because intended so seriously.
When such open evils can be so ignored, what wonder that the more occult sources of malaria should not be arrived at? And when will they be understood while accusations against particular insects require to be held in reverence as dogmas? In the F. M. S. Report for 1911 Dr. Sansom allows (p. 3) “there exists in the minds of a great many people a doubt whether the
mosquito carries malaria or any other disease”; and proceeds to add “until this heresy has been corrected.” Heresy indeed! Is not free thought the first fundamental of science? Having thus labelled disbelief in his theory, Dr. Sansom in his next Report for 1912 has to admit (p. 5), “I have visited many (rubber) estates where anti-malarial work has not been completed or even begun, so that infection remains as bad or nearly as bad as ever, yet, from the time the laborers have been fed, down has come the death-rate.” If food has so much to do with the trouble, why lay all the blame on Lady Anopheles?
And just as too little food helped to make the coolies ill, is it not likely, if it be not rude to ask, that too much food was part cause for the malaria that troubled the prosperous members of the community of Kuala Lumpur, the Federal Capital, so long as a need of drainage left much to be desired in their surroundings? Who acquainted with the Far East does not recall the many courses of the Chinese cook, and the constant refilling of the champagne glass at dinner parties? There seems small wonder that the carnivorous feeder and spirituous drinker from a chilly latitude should fall a victim in the East to malarial and other fevers: and this without any assistance from Lady Anopheles or her sister mosquitoes. To her a meed of praise would seem due, for where the mosquito exists there is proof of a need of drainage, clearance, and general sanitary attention. But man, who has stoned the prophets throughout the ages, equally execrates the insects that come as warnings.
That non-proven is the verdict upon Lady Anopheles’ guilt seems well shown by Dr. Fraser’s Report, incorporated with the general Medical Report for the Federated Malay States for the year 1911.
After rather shakily chanting the orthodox creed of the mosquito theory, Dr. Fraser negatives faith by fact in the most heretical manner. “It appears to have been assumed on inadequate grounds,” he writes, “that a small number of malaria-carrying species in an area is necessarily associated with a low incidence of the disease. Certain observations made in the course of the present inquiry would appear to controvert this view. On some estates where the maximum spleen and parasite rates prevailed
few anophelines of any sort were to be found, while in other areas, where malaria-carrying anophelines were numerous, these rates were low. Also it was noted that where different classes of laborers were under identical conditions so far as the mosquito factor is concerned, such as free and indentured laborers on the same estate, the parasite rates varied widely in the two groups. It is clear that factors affecting the general well-being of laborers, such as the quality of the food supply, housing, etc., are by no means negligible in the prevention of malaria, as they are equally not negligible in the prevention of other diseases. To these factors attention must be directed as well as to measures which aim at the reduction of mosquitoes, if the disease is to be combated successfully in the conditions which obtain in this country.”
Precisely! We must attend to general sanitation and personal hygiene, and then, having removed the beam from our own eye, we may be able to see clearly to cast out the mote in the eye of the Lady Anopheles.