Chapter XLIII: Anthrax--Its Relation to the Wool Industry

Wool has been woven into the industrial history of the world, and has been an important factor in the progress of nations from savagery to civilisation. In all ages, “flocks and herds” have represented peace and prosperity, and only within recent years has it become known that the fleeces, hides, flesh, and other products of animals which die from anthrax sometimes convey the disease to man.

The word “wool” in its technical meaning comprises sheep or lamb’s wool, goat’s wool or hair (mohair), camel’s wool or hair, alpaca, and other allied textile fibres. The quantities and origins of these for manufacturing purposes in the year 1900 were nearly as follow, in million pounds weight:--

From the United Kingdom 141
„ British Possessions 448
„ Foreign Countries 105
„ „ Mohair 22
„ „ Alpaca 6
---
722
Exported in the “raw” state 220
---
Balance for home use 502
===

The “clip” of wool of the United Kingdom is practically what it was fifty years ago. The total imports of wool, goat’s hair, and alpaca, have increased fourfold during the same period. This increase represents the growth of the wool industry in the West Riding, there having been little increase in other parts of the Kingdom. It is probable that “three-fourths of all the wool used in this country is consumed within a radius of fifteen miles from Bradford.” The longer and finer combing wools, including almost all the mohair and alpaca, are manufactured into “worsteds”--stuffs--for which Bradford is the commercial centre. The shorter and coarser felting wools are made into “woollens”--cloths--of which Leeds and Huddersfield are the most important producers; others are used at Halifax and Kidderminster for carpets, and also at Leicester for hosiery.

Previous to 1837, when alpaca and mohair were imported from Peru and Asia Minor respectively for use as textile fibres, no specific disease had been associated with wool. Ten years afterwards, owing to recurring deaths of sorters, a suspicion arose that these materials were in some way or other the cause of the peculiar, rapid, and fatal illness which became known as “wool-sorter’s disease.” When these sudden deaths followed each other at several months’ interval they did not attract much attention, but when sorters died within a few weeks from a similar and unusual disease, the workpeople became alarmed, and their fears were increased when no reasonable explanation could be given as to the nature of the illness, its prevention or its cure. In the hope of solving the mystery, many _post-mortem_ examinations of the bodies of wool-sorters were made by leading medical men in the large towns of the West-Riding, and the suspected materials and dust arising from these were submitted to experts for microscopical examination and chemical analysis. These investigations and reports extended over more than thirty years without arriving at a satisfactory explanation. In 1877 a case of this disease came under the writer’s observation; the man was apparently well in the morning on leaving home for work, and died seventeen hours after the first feeling of illness. It was evident that this fatal collapse without pain or distress was not from any well-known disease. In 1879, when visiting such a patient--who died twelve hours afterwards--he took some blood from the arm, and within a few minutes two or three drops of it were injected under the lumbar skin of a rabbit, a guinea-pig, and a mouse respectively. The animals died within sixty hours, and the blood of each showed the presence of bacilli. Another animal was inoculated with the blood from one of these, and it died in a shorter time. The fluids from this animal were found to be crowded with the _bacillus anthracis_, and the disease was recognised to be anthrax. (_Lancet_, vol. ii., 1879, pp. 920, 959.)

Anthrax is a contagious disease, and of the widest distribution. It readily attacks most wool-bearing animals, and is found in all countries, being very prevalent on the Continent of Europe, in Asia, South Africa, and South America, and occurring less commonly in the United Kingdom, North Africa, North America, and Australasia. The incidence of anthrax among animals in Great Britain varies very much, some counties having no outbreak year after year, while from others it is never absent. It is most prevalent in the West-Riding, and the counties of Leicester, Northampton, and Norfolk, in all of which foreign wool, hair, hides, or other animal products are used in industrial processes. The number of sheep and lambs in Great Britain in 1900 was 28,000,000, and the number reported to the Board of Agriculture to have died from anthrax during the year was 40. For 1899 the number of deaths was 69. The risk of infection from home-grown and colonial wools is so slight that it may be disregarded. The most noxious wools are those from foreign countries where anthrax is prevalent, the wool being dry, dusty, of low quality, and having very little “yolk.” (Yolk is a peculiar unctuous substance, chiefly consisting of a potash soap which pervades the wool and protects the animal from the effects of rain and cold; it also nourishes the wool, rendering it soft, oily, and pliable.) It is equal in weight to 7 or 8 per cent. of the “raw” fleece. Alpaca, mohair, camel’s hair, Persian, and inferior dry Eastern wools have very little yolk, and are dangerous to handle if they contain “fallen fleeces.” The greater amount of yolk or grease in South American and other foreign wools appears to fix the anthrax spores, and renders the wool almost innocuous to the sorters.

The essential cause of anthrax is a micro-organism, the _Bacillus anthracis_, the spores of which can only produce their specific effect when they gain access to the circulating blood by way of the skin, the lungs, or the stomach; hence there are three types of the disease: the cutaneous, the pulmonary, and the intestinal.

1. _Cutaneous Anthrax._--This presents two varieties, viz., malignant pustule and erysipelatous anthrax. The malignant pustule was first noticed in England in 1854, and recorded in 1863. It must have occurred frequently in the Bradford Worsted District for more than thirty years before it was diagnosed as anthrax in 1880. This form of cutaneous anthrax in wool-workers is very much the same as that which appears in hide-dressers and others.

_Erysipelatous anthrax_, of which _œdematous anthrax_ is a milder manifestation, has, until recently, escaped recognition in this country. It was first noticed by Bourgeois in Provence, France, in 1834, and his observations were published in 1843. He wrote afterwards a very complete account of it in his book on _La Pustule Maligne et L’Œdème Malin_, 1861. Subsequent writers have been almost entirely indebted to this author for their statements.

_Symptoms._--Bourgeois says: “It begins as a pale swelling, soft and without pain. It is only after several days, and when more fully developed, that vesicles and eschars form, notably on the eyelids, but at the onset the skin is smooth and has no trace of a pimple.” The local symptoms are the extensive œdema, in slight cases, without redness, vesication, or eschar; in severe cases, with redness, vesication, and a gangrenous appearance of the skin. The general symptoms are of a negative character; there may be no pain, no distress, and no fever. Even in fatal cases these are not very marked.

_Diagnosis._--The appearance of the patient is so like that of one with ordinary erysipelas that the differences might easily be overlooked, were it not that there is so little constitutional disturbance. The absence of injury, pain, and fever will distinguish it from acute emphysematous gangrene. The only proof, however, is the finding of the characteristic bacillus in the blood or fluids by cultures and physiological tests.

_Prognosis._--This form of anthrax is stated to be much more fatal than malignant pustule; of seven cases seen by the writer, three were fatal.

CASE.--J. G., æt. 29, a willower of low class wools, had been ailing several days when visited on 12th March 1899. The right upper eyelid was greatly swollen, red, and hard, there were several vesicles, nearly the size of kidney beans, which contained a clear gelatinous, straw-coloured serum; pulse 88, temperature 100.5°. March 13th, neither eye could be opened, the right ear was doubled on itself, the scalp pitted on pressure, and he was slightly delirious; pulse 76, temperature 101.8°. March 14th, other vesicles on the cheek, much swelling of submaxillary glands and neck; pulse 88, temperature 101.8°. After a few days, black eschars appeared on the eyelids, the swelling subsided, and he was convalescent. March 17th, pulse 72, temperature 98.9°. Serum taken on 12th March for cultivation yielded positive results.

2. _Pulmonary Anthrax._--“Wool-sorters’ Disease.”--From the year 1846, when this disease was first noticed in the neighbourhood of Bradford, to 1877, it had not been known to attack other persons than the sorters of alpaca and mohair. In subsequent years it was found that camel’s hair, Persian, and other dry, dusty, low class foreign wools, were also infective; and further, that any person might be attacked if exposed to the inhalation of anthrax spores in dust arising from the products of dead animals.

_Symptoms._--The absence of troublesome symptoms is very remarkable. There may be no rigor, pain, cough, vomiting, purging, or other distressful conditions. Even when dying, the patient may not feel particularly ill. In ordinary cases, at the commencement, there is a chilliness or slight shivering, the tongue is moist and thinly coated, thirst is present, and the appetite indifferent, with some nausea and uneasiness at the stomach; vomiting is common (if this is only at the commencement it is not of much moment, but if persistent or commencing after two or three days it is of serious import, indicating the extension of the disease to the stomach and bowels.) The lungs are always affected, although sometimes only slightly. Nearly all patients have a feeling of tightness, weight, and oppression about the chest, which embarrasses the breathing. Cough is generally present, but never very troublesome; in one-third of the cases it was absent, or very slight. In most there is no expectoration, but in mixed cases, which continue over five days, there is some, which is occasionally rusty coloured. The purer the infection, however, the less likely is there to be any pneumonia. There is a dusky, leaden hue, with coldness of face, ears, and fingers in the collapse stage. Percussion sounds are generally clear; occasionally there is some dulness, mostly at the base of the right lung; the respiratory sounds are feeble and almost inaudible on this side, with some sibilant sounds; moist bronchial râles may be present later on, but rarely crepitations. In cases where no dulness on percussion was detected a few hours before death, not unfrequently a considerable quantity of fluid has been found in the pleural spaces at the _post-mortem_ examination. In the early stage the pulse may not differ from the normal as regards frequency; later it is small, feeble, irregular, uncountable, and out of keeping with the apparent slight character of the illness. The heart’s sounds are also very weak and may be inaudible. In most cases the mind keeps clear to the end; in some with cerebral lesions, there are struggling, convulsions, and coma. The skin is always moist and often bathed with perspiration. The temperature seldom reaches 103°; when more than this, the infection is mixed, causing septic pneumonia. Generally the temperature is from 3° to 5° higher in the rectum than in the axilla. As the illness advances, the temperature falls. The urine is scanty and high-coloured. In one case the sp. gr. was 1040. In several cases albumin was found, in one equal to two-thirds of the quantity of urine in the test-tube. Sugar is also occasionally present.

The cases clinically arrange themselves into three classes: (1) Rapid, in which death takes place within two days, from collapse without any reaction. (2) Ordinary, in which the initial depression is followed by reaction and death within four days. (3) Prolonged cases, in which there is pneumonia from mixed infection, and death after the fourth day.

_Duration of Illness._--Number of cases fatal within--

1 day 2 days 3 days 4 days 5 days 10 days over 10 days Total
5 19 19 16 7 7 2 75

_Diagnosis._--In a rapid case this is easy; the patient when first visited is seen to be dying from continued uncomplicated collapse, which if there has been exposure to infection should not be mistaken for any other disease. In ordinary cases during the first two days diagnosis is impossible, the symptoms are not severe, and are such as are met with in common ailments; it is only when the illness becomes more pronounced by the patient’s strength and his heart failing without other sufficient reason that a diagnosis may be made. In prolonged cases the uncertainty is still greater; the pleuritic and pneumonic conditions mask the purely anthrax symptoms so much, that it is only by a _post-mortem_ examination that the true nature of the illness can be known.

_Prognosis._--In all cases this is unfavourable; symptoms are unreliable; what appears to be nothing more than ordinary catarrh in a person who has been exposed to anthrax infection may suddenly terminate fatally from heart failure. In the more prolonged cases, which are mixed with septic pneumonia, death may occur unexpectedly. It is probable that many cases of pulmonary infection recover; such cases have been reported, but in none has the diagnosis been confirmed by exact experimental methods.

_Incubation._--The period of incubation is uncertain. The exact time of infection cannot be fixed as in cases of traumatic cutaneous anthrax. No case of pulmonary anthrax has been recorded which was due to only one exposure to infection. Sorters of noxious materials may work exposed to the risk of infection almost daily for years without any noticeable effect from it. It is only when the virus gains access to the blood stream through some accidentally open gateway that serious illness follows. Judging from what takes place in cutaneous cases we may presume that when the spores pass the respiratory epithelial barrier they will produce some local specific effect within twenty-four hours. Infective material may be present on the skin or the mucous membranes several days before it gains access to the blood and produces any noticeable effect.

_Pathological Changes: External._--The appearance of the body twenty-four hours after death varies considerably. The discoloration of decomposition appears very soon, attended with more than the usual lividity, which is not confined to the posterior surface of the body. The face is sometimes very much swollen and discoloured. The cellular tissue of the neck and upper part of the chest may be distended, gangrenous-looking, and emphysematous. In many cases the cause of death may be surmised from the external appearance of the body alone; in other cases there is no unusual discoloration excepting that the tips of the fingers are cyanosed. Between these two conditions there is every gradation of external appearances. _Internal._--On cutting the skin of the chest where it is much discoloured serum and air bubbles escape. The muscles are dark coloured. On removing the sternum the cellular tissue beneath is sometimes emphysematous; more frequently there is much gelatinous œdema and occasionally it has been seen infiltrated with blood. The pleural spaces almost invariably contain a large quantity of clear straw-coloured serum, generally more on the right side. Gelatinous infiltration under the serous covering of the lungs and between the lobes may be one inch in thickness without any plastic inflammatory exudation. On section the lungs are seen to be engorged with dark-coloured blood, some portions being more solid than others, and of a blacker red colour. It is not uncommon to find infarcts of blood in the parenchyma of the lungs, and these in prolonged cases may have broken down and become purulent. The bronchial glands are enlarged, and more so on the right side; the mass may be the size of a hen’s egg. The trachea and bronchial tubes contain frothy blood-stained mucus; the mucous membrane is claret-coloured and swollen, and beneath it are frequently small infarcts of blood. The connective tissue at the root of the lungs and base of the heart is sometimes œdematous and extensively infiltrated with blood. The pericardium, epicardium, and endocardium frequently show subserous petechial spots, and the pericardial fluid may be increased to five or six ounces. The blood is nearly always fluid and of a dark, almost black colour. The heart may be empty or contain fluid blood in all its cavities. The colour of its lining membrane varies from a pale cherry red to dark chocolate. The abdomen does not contain much fluid unless the intestines have been involved, when the quantity may be from two to four pints. The gelatinous œdema is sometimes very considerable in the mesentery and the cellular tissue surrounding the kidneys. Extravasated blood in small or large quantities is also seen in a few cases in the mesentery or in the connective tissue around the kidneys. The stomach and intestines frequently show numerous patches of extravasated blood; if these are considerable in size they are seen on both the mucous and serous surfaces. The spleen, like all other organs in this disease, varies very much. It is generally larger than natural, but not unfrequently it is unaltered in size and appearance. The liver and kidneys are less frequently affected than other organs. The brain is occasionally completely surrounded by blood extravasated between the membranes. Small infarcts are sometimes seen in the cerebral substance. The characteristic changes are: 1. The discoloration of the skin, especially about the neck and upper part of the chest. 2. The gelatinous œdema under the sternum, about the base of the heart, in the mesentery, the omentum, and the adipose tissue around the kidneys. 3. The extravasations of blood, which may be extensive, in the chest, the abdomen, or the head, with smaller hæmorrhagic areas and petechial infarcts in any organ or any part of the body. 4. The serous effusions into the pleura, pericardium, and peritoneum. 5. The dark colour and fluid condition of the blood. Many coarse changes are present in every case, but no single lesion is found in all cases. There may be no unusual discoloration of the skin, no gelatinous œdema, no large or numerous small extravasations of blood, or even serous effusions, but one or more of these in various degrees is always present.

3. _Intestinal Anthrax._--Only one case of primary intestinal anthrax has been observed in wool-workers, and that recently. A wool-sorter, aged 29, on leaving work felt weak and as if he had a lump at the stomach. The following day he was sick and restless; on the third day the pulse was 86, temperature 99.2°; on the fourth day brown-coloured blood was vomited, and several tar-like stools were passed. Thirteen hours before death he was in a collapsed condition; pulse 112, small and almost uncountable; respiration 26. The lungs were not involved. Duration of illness, 4½ days.

_Distribution of the Bacilli._--These are found in the swollen mucous membrane of the trachea and larger bronchi, being most numerous in the neighbourhood of small hæmorrhages, and only a few in the lung tissue. The gelatinous serum never contains large numbers. The serum from the chest and abdomen, being a pure cultivation fluid, generally contains large numbers of bacilli of shorter or longer lengths. Bacilli are very unequally distributed throughout the body; they may not be found in the spleen, but in the fluids and tissues near pathological lesions.

Inoculations of rodents with blood taken from a patient twelve hours before death does not always produce fatal anthrax, a result which is inevitable if the blood be taken two or three hours before the event, even if on microscopical examination it gives no evidence of containing bacilli. Inoculations with gelatinous and pleural serum taken within twenty-four hours after death may have no effect on rodents, but generally they are fatal. All fluids and tissues which are fresh and contain the characteristic bacilli give rise to anthrax when inoculated into the blood stream of susceptible animals, but if not used for two or three days this effect may not follow.

_Preventive Measures._--Noxious wools of foreign origin sometimes include “fallen fleeces,” which are easily recognised; these should be picked out, classed apart, and disinfected by steam.

_The Precautionary Regulations_ agreed upon at Bradford in 1884 were adopted by the Home Office in 1899, and have the force of legal enactments. They provide that bales of alpaca, pelitan, cashmere, Persian and camel’s hair, shall be opened over a dust-extracting fan, so arranged that the current of air shall draw the dust away from any workman in the room. Badly-damaged wool or hair, van mohair, “fallen fleeces,” and foreign skin wool shall be damped with a disinfectant, and then washed without being put through any dust-extracting machine. The dust collected by the willows or other dust-extracting machine from the open boards--wire-work--shall not be discharged into the open air; it shall be removed weekly and afterwards burnt. No person having any open cut or sore upon any part of the body shall be allowed to attend to any willow or dust-extracting machine. No bale of wool or hair shall be stored in a dust-extracting room. Requisites for slight wounds shall be kept at hand. Appliances for washing shall be provided for the workers in the warehouse and dust-extracting rooms. No meals shall be taken in the willowing or carding room. These regulations have had a beneficial effect in reducing the number of cases of anthrax, but they are not sufficient to eradicate the disease. If bales of noxious wool or hair were placed in steamers, and submitted to a steam pressure of six pounds to the square inch--230° F.--for a few hours, all bacteria would be destroyed. Such a regulation should be enforced wherever noxious wools or hairs are used in the United Kingdom.

_Treatment._--It is to be regretted that in such a fatal disease so little can be done in the way of treatment. The progress of the illness is often so rapid that before a diagnosis can be determined the patient is in a hopeless condition. If the patient is seen before any signs of collapse are apparent, perhaps the inhalation of non-toxic germicides in the form of spray, and the intravenous injections of these may give the best chances of success. We may look forward with confidence to the time when we shall be able to treat the disease more successfully by antitoxines; hitherto these have been used only in external cases.

JOHN HENRY BELL.