Report of the Departmental Committee apointed to inquire as to precautions for preventing danger of infection from anthrax in the manipulation of wool, goat hair, and camel hair.

Great Britain. Committee on Anthrax.

Date:: 1918

Credit: Report of the Departmental Committee apointed to inquire as to precautions for preventing danger of infection from anthrax in the manipulation of wool, goat hair, and camel hair. Source: Wellcome Collection.

23/356 (page 15)

$blood run on to it direct from the throat of a healthy ’sheep. Bloodclots of Series E 2 were exactly similar to those of E 1, except that, instead of uninfected healthy blood direct from the sheep’s throat, blood infec ted as in Series D was used. Bloodclots of Series EK 3 were prepared exactly in the sanie way as those of’ Series D. In the preparation of clots of Series E 4 the wool in the vessels was first saturated with infected blood serum, obtained during the preparation of bloodclots of Series EK 2, and subsequently fresh clots of blood . infected as in Series D were pressed into the wool till the fibres were completely surrounded, In order to hasten the drying of the bloodclots of Series EH, the desiccators containing them were placed about 3 feet from a gas fire used intermittently, but frequently for long ‘periods during the day, for warming the laboratory. ‘They certainly became hard and dry more quickly than other clots, but, because of the high temperature to which they were raised in this method. of drying, ‘they were far more refractory than any clots, whether. artificial or natural, examined in the course of the inquiry. Apart from the large size of some of them, they were all abnormally difhicult to break up in the disinfecting process, After passing through it, a remnant or several remnants of blood which it was impossible to tease out:in the ordinary way almost always remained, and they varied in thickness from one-eighth to half an inch. Professor Delépine has informed: us that: he prepared bloodclots by a method somewhat similar, and found the same difficulty, He therefore made experiments with clots dried at various temperatures, and found that the effect of heat was to render the clot quite insoluble (see his report).\ With this added testimony it appears to be beyond doubt that. the-peculiar. refrac- toriness of the various varieties of the Eseries of clots was due. to overheating. In many cases partiof the clot was found to be refractory, while the remainder behaved as usual. In ‘consequence of the method of arrangement in the desiccators some parts of ‘the clot were protected by wool or other clots from the direct action of the fire, and no doubt these parts were more soluble than those parts exposed to direct heat. There’ was no: observable difference in the behaviour during disinfection of the: different varieties of clots in Series E nor in the results obtained. \Bloodelots of the E series were very highly infected, and. con- tained from 6,000,000 spores per clot in Series E. 3 (blood only infected) to 20,000, 000 spores per clot-in Series EK. 1 (wool only infected). Since in Series EH 2 and E4 both bol and blood were infected to the same-extent, and from the same sources as the wool and blood in E 1 and E 3, respectively, the spores in clots: of these two. sub-series must each have contained more than 20,000,000 spores. Serves fF, (Made March 6th, 1917.. Used in experiments, from April 13th to April 17th, 1917.)—These were prepared in two varieties, clots of Series I 1 being exactly aintilae to. those of Series D and E 3, and clots of Saries I 2 beimg. exactly ear to those of Series E 4. In behaviour they very closely resembled eee of Series D. Serves G. (Made July 18th, 1916. Used October 3rd, 19i6.)—This consisted of one clot only, which was made from the blood of'a beast’ which’ had been killed in ‘the Bradford Abattoir. It was apparently healthy when killed; but after death the state of certain orgais caused anthrax to be suspected. A small quantity of blood was therefore sent to Dr. Eurich’s laboratory for examination, and ‘anthrax bacilli were found to be present in quantity. ‘The blood was clotted to’ some extent when received (about an hour after the animal was killed) and was pressed into wool. When dried, the clot was somewhat different’from the artificial clots prepared from healthy blood. A ‘small portion of the dried clot was teased out for control. purposes, and it was noticeable that the blood dissolved very much more readily than dried clotted healthy blood. - It, in fact, behaved much in the same manner as the citrated blood of the clots of Series C. It was unfortunately not found possible to obtain more of this naturally infected blood. : Summing up the characteristics of the various series Gf artificial bloodclots as oe by the experiments, it was found that— _ Bloodelots of Series A and B consisted of a comparatively large amount of wool with correspondingly less blood, and it was comparatively easy to remove the protection afforded by the blood to the spores. ‘They appeared to behave very much in the same way as and to be about as difficult as natural uninfected clots. _. Those of Series C, made from citrated blood, also consisted of a comparatively large amount of wool, the blood was more soluble than ‘healthy blood, and it was comparatively easy to remove the protection of the spores. They resembled natural infected clots, but were, generally speaking, easier to disinfect than any others of the bloodclots used in the experiments, and the blood could be removed from the wool more readily than from natural clots free from anthrax spores. Bloodclots of Series D consisted of a comparatively large quantity of blood with proportionately less wool. Portions of the blood were in thick masses not penetrated by much wool, and it was difficult to remove the protection afforded to the spores, since the blood C 4$