Parasites: A Treatise on the Entozoa of Man and Animals / Including Some Account of the Ectozoa

by T. Spencer Cobbold

“Dr Dickinson, of Workington, tells me that he was at first suspicious that his patients were suffering from fever, but was not quite able to make out what the disorder was. At length certain symptoms occurred, which suggested that it might possibly be the German flesh-worm epidemic making its appearance in this country for the first time, and, therefore, in view of verifying the facts of the case, he sent me portions of the flesh of the pig. He describes the symptoms, which in their character corresponded with those previously recorded as experienced by persons similarly attacked. Dr Dickinson remarks, towards the close of his communication, that the victims form a small family who have carefully reared their own swine. The British farmer is thus here introduced to us at his own table playing the part of ‘host’—at her own table, I should say, for, to be more precise, it is a widow, her daughter, and a man-servant who are suffering. Dr Dickinson informs me that for two or three weeks before he was called to see them they had been eating sausages and boiled pork from one of their own home-fed pigs, which pig, by the way, turns out to have been an old sow. He brought away some sections of the leaner portions of the flesh for microscopic examination. You will observe that there can be no mistake about the source of the food on this occasion. Hitherto, Trichina has not been observed in our British-fed swine in more than one or two, or possibly three instances. Therefore it would be very interesting to ascertain how it happened that this poor pig became trichinised. In my communication addressed to the ‘British Medical Journal,’ I wrote as follows:—“Dr Dickinson has at the present time under his care a family suffering from the so-called flesh-worm disease, resulting from the consumption of ham prepared from pigs reared by the family themselves. A portion of ham sent to me swarmed with recently encapsuled Trichinæ. Dr Dickinson being thus the first person who has diagnosed trichiniasis in the living subject in England, I hope he may be induced to give us further particulars.” The editor, in commenting upon this letter, added a practical point, which I wish especially to bring to your notice. He says:—‘The subject of parasitic diseases of domestic animals is one of widespread and increasing interest. It is immediately related to the irrigation of fields with sewage.’ The editor, of course, made this statement on independent grounds, and on his own responsibility. If he had said the subject bears an indirect relation to the sewage question, he would have said no more than is absolutely true, for, as I shall take occasion to explain, there is every reason to suppose that certain forms of parasitic disease may be propagated by means of sewage. In this connection some of you may be disposed to ask the question:—‘Are there any sources of comfort to be gathered from the facts?’ Or you may say, supposing that in future our British swine are not as free from Trichinæ as they have been hitherto, can we possibly avoid the contingency of playing the part of host to those creatures? Certainly, I reply, it is simply a question of properly cooking the food. If these farmers have not cooked their food at all, or scarcely at all, that will at once account for their being laid up. I should tell you that the lady and the daughter are recovering, and that they are convalescent, but the man-servant is very ill. If, during cooking, the flesh consumed by these persons had been raised to a persistent temperature of 170° Fahr., then, doubtless, the ingestion of trichinised pork would have done no harm. You observe that Dr Dickinson says in his letter that they partook of it roasted and boiled. Now, few of us are in the habit of eating underdone pork, although there are other meats that we devour very readily in an imperfectly cooked state. It must be remembered, also, that although the exterior may have been subjected to a temperature of 212 degrees, it by no means follows that the whole of the joint throughout must have been submitted to that temperature. Under rapid cooking, the centre of a large joint may remain much below even 140 degrees. If the man-servant ate only one ounce of the flesh with living Trichinæ in it, he will probably have at this present moment at least 42,000,000 of these guests in his muscles. You will ask, ‘Will he recover?’ ‘Yes; if he ate no more than that.’ If he has eaten 2 oz. thoroughly underdone, depend upon it he has 80,000,000, and if he has eaten 3 oz. he will have over 100,000,000 of Trichinæ in his muscles. Could he survive if he had eaten over 3 oz., and thus have 100,000,000 and upwards of these inhabitants? I think he could. We have evidence on this point from the case in which I estimated that there were upwards of 100,000,000 of Trichinæ present, and yet the man survived the attack.

“Incidentally I may remark that in the course of the last twenty years, although millions of parasites and their eggs have passed through my hands, I have almost entirely escaped infection. It is something to know what you are either handling or looking at, because there are many parasites besides Trichina which are dangerous. There are gregariniform entozoa residing in meat which we eat every day without any bad consequences. They are as harmless as cheese-mites. There is no need to be in the slightest degree nervous about flesh-food, provided it is properly cooked. I believe there will be no fatal issue in the case of any of the three individuals just alluded to, but the chief practical point before us arises out of the fact that we have here, for the first time in England, an epidemic of trichiniasis. By calling attention to the subject, it will, to say the least, suggest precautions by which future epidemics may be avoided.”

The above remarks form the substance of a lecture given on the 24th of April, 1871. A week later I delivered the third of the Cantor lectures for that year, when I took occasion to add the following particulars:

“It has been asked whether the so-called muscle-Trichinæ, after they have arrived at their destination within the flesh of man, are capable of producing any more unfavorable consequences? The answer is, Certainly not. In the case of man it would be necessary that his muscles should be eaten in order for the Trichinæ to become sexually-mature worms; and in those countries where cannibalism exists, the man-eater would himself become trichinised, and would certainly deserve his fate. I was very desirous to follow up the account of this outbreak by inquiries respecting the particular animal which had been the cause of the outbreak. I may therefore mention that my informant, Dr Dickinson, states that the family, including the man-servant, all fed together, and that they had for upwards of a fortnight eaten daily, and sometimes twice a day, sausages made from the flesh of the trichinised animal. And he adds: The meat cut from the ham and flitches, and what is called the spare-rib, was roasted before the fire or in the frying-pan. Occasionally it was cooked in the oven. Dr Dickinson ascertained from the mother that she liked her meat to be underdone, and thus, therefore, there is very little doubt that the meat was generally undercooked. The man, a strong labourer, had a good appetite, and would therefore get a large share. He is improving slowly. Dr Dickinson adds in a postscript, what is still more to the point, that the sausages would be most likely undercooked; they would be cooked in the frying-pan, and if only brown on the outside would be eaten. It is probable that the outbreak was due therefore to eating underdone meat from this pig, cooked in various ways, and not alone from the ham itself.”

If the facts connected with this outbreak be honestly faced, it must be rendered clear to any unprejudiced observer that Dr W. Lindow Dickinson was the first person to observe, recognise, and treat the Trichina disorder in this country. No other English, Scotch, or Irish physician has encountered any similar case. If I lay stress upon this fact it is because I have learned from Dr Dickinson that another person has asserted priority in this relation. Sir Dominic Corrigan is stated to have told a gentleman in the House of Commons, “that he had often met with trichiniasis in his practice in Dublin,” further averring that the disease “was quite common in many parts of Ireland.” If Sir D. Corrigan merely desired it to be understood that he had repeatedly encountered the Trichina at post-mortem examinations, then there is nothing surprising in his statement, but if, on the other hand, the disease itself has been frequently recognised in the living Irish human subject, one can only express astonishment that hitherto no single instance of the kind appears to have been recorded either in the public or professional journals.

Bibliography (No. 21).—English Literature.—Allman, G. J., “Exhib. of Specimens,” ‘Micr. Jrn. and Structural Record,’ 1842, p. 94.—Althaus, J., ‘Essay on Trichinosis,’ London, 1864.—Idem, “On a Suspected Case,” ‘Med. Times and Gaz.,’ 1864, p. 161; see also pp. 362 and 390.—Atwood, see Belfield.—Ballard, E., “On Diseased Meat,” ‘Med. Times and Gaz.,’ 1864.—Belfield (with Atwood), “Trichinæ in Pork;” ‘New York Med. Rec.,’ Dec. 28, 1878; ‘Med. Times and Gaz.,’ Feb. 15, and ‘Lancet,’ Feb. 22, 1879.—Bellingham, O. B., ‘Dublin Med. Press,’ 1852.—Bowditch, H. J., “Cases of Trichina,” ‘Boston Med. and Surg. Journ.,’ 1842–43–44.—Bristowe, J. S. (and Rainey), ‘Trans. Path. Soc.,’ 1854.—Chevers, N., “Sanitary Efforts in regard to Trichiniasis,” ‘Lancet,’ 1864, vol. ii, p. 733.—Cobbold, T. S., “On the Discovery of Trichina, in relation to the question of Priority,” ‘Lancet’ for March 3, 1866, p. 244.—Idem, ‘Parasites, and the part they play in the Economy of Nature’ (lecture), Manchester, 1873, p. 46; also in the ‘Veterinarian,’ March, 1874.—Idem, Remarks in the ‘Journ. Soc. of Arts,’ 1866, p. 399; also in ‘Med. Times. and Gaz.,’ 1867, p. 24; also in ‘Lancet,’ Feb., 1864 and 1866, p. 538.—Idem, ‘Our Food-producing Ruminants and the Parasites which reside in them’ (Cantor Lectures), 1871.—Idem, “Experiments with Trichina,” ‘Proceed. Linn. Soc.,’ vol. ix, p. 205, 1867; see ‘Lancet’ for Jan. 13, 1866, p. 52; ‘Brit. Med. Journ.’ for Dec. 22, 1866, p. 713; also ‘Lancet’ for Jan. 9, 1867, p. 91.—Idem, “Worms” (l. c., Bibliog. No. 2, Lecture xviii), 1872.—Idem, “Outbreak of Trichinosis in England,” ‘Brit. Med. Journ.,’ 1871, p. 435.—Idem, “Trichinæ in Fish” (alleged to have been found in a pike by Dr Elendenen at Ostend), in the ‘Lancet’ (anonymous annotation) for Nov. 16, 1878.—Curling, T. B., two cases, ‘Lond. Med. Gaz.,’ 1836.—Davaine, C., quoted in ‘Brit. Med. Journ.,’ see foreign lit., below.—Delpech, abstr. of his Report, ‘Brit. Med. Journ.,’ 1866, p. 375.—Dickinson, W. L., ‘Brit. Med. Journ.,’ 1871.—Elendenen, “Trichinæ in Fish” (newspaper report respecting his “find”); see Cobbold, above.—Farre, A., “Observations,” ‘Lond. Med. Gaz.,’ 1835–36.—Friedreich, N. (trans. by Ogle), ‘Med.-Chir. Rev.,’ 1863, repr. in ‘Edin. Vet. Rev.,’ 1863.—Furstenburg, ‘Edin. Vet. Rev.,’ 1864, p. 513.—Gordon (see Chevers).—Gamgee, J., “On Diseased Meat,” ‘Pop. Sci. Rev.,’ 1864.—Goodsir, J., ‘Month. Journ. Med. Sci.,’ 1842.—Harr, ‘Bost. Med. and Surg. Journ.,’ 1866, p. 532.—Harrison, “On a peculiar Species of Entozoon occasionally found in the Voluntary Muscles of the Human Subject,” ‘Rep. of Brit. Assoc.,’ Aug. 12, 1835; in ‘Dub. Journ.,’ vol. viii, 1835–36; in ‘Lond. and Edin. Phil. Mag.,’ and in ‘Amer. Journ. Med. Sci.,’ vol. xviii, p. 187, 1836.—Herbst, “Trichinæ in the Badger,” ‘Assoc. Med. Journ.,’ 1853, p. 491.—Hilton, J., “Notes on a peculiar appearance observed in Human Muscle, probably depending upon the formation of very small Cysticerci,” ‘Lond. Med. Gaz.,’ vol. xi, p. 605, 1833.—Jackson, J. D., “Trichiniasis,” in ‘Hay’s Amer. Journ.,’ 1867, p. 82.—Kiefer, H., cases, ‘Bost. Med. and Surg. Journ.,’ 1866, p. 208.—Kobelt, ‘Micr. Journ. and Struct. Rec.,’ 1842, p. 147.—Kratz, “On the Hedersleben Epidemic,” ‘Brit. Med. Journ.,’ 1866, p. 76.—Krombein, “Trichiniasis in New York,” ‘Amer. Journ. Med. Sci.,’ 1864, and ‘Med. Times and Gaz.,’ 1864, p. 292.—Küchenmeister, F., Symptoms, &c., ‘Lond. Med. Rev.,’ 1860, p. 457.—Langenbeck, case, ‘Edin. Vet. Rev.,’ Feb., 1864.—Leidy, J., “Trichina in the Pig,” ‘Annals of Nat. Hist.,’ and ‘Pr. Ac. N. S. Philad.,’ 1847.—Leuckart, R. (translations from), in ‘Ann. Nat. Hist.,’ 1860; in ‘Qrt. Journ. Micr. Sci.,’ 1860; and in ‘Bost. Med. and Surg. Journ.,’ vol. liii, p. 198, 1860–61.—Liveing, R., “Path. Soc. Rep.” in ‘Med. Times and Gaz.,’ 1865, p. 374.—Mosler, “On Trichinous Flesh,” ‘Brit. Med. Journ.,’ 1864, p. 554.—Idem, “On Benzine in Trichinosis,” ‘Med. Times and Gaz.,’ Oct., 1864, p. 444.—Nunneley, T., ‘Brit. Med. Journ.,’ 1866, p. 252.—Owen, R., “Description of a Microscopic Entozoon infesting the Muscles of the Human Body,” ‘Proc. Zool. Soc.,’ and ‘Lond. Med. Gaz.,’ 1835; ‘Trans. Zool. Soc.,’ vol. i, 1835.—Idem, Remarks in ‘Journ. Soc. of Arts,’ 1866, p. 399.—Paget, J., “Letter relating to the Discovery of Trichina,” ‘Lancet,’ March, 1866, p. 269.—Rorie, J., Letter, ‘Lancet,’ Feb., 1864.—Salisbury, J. H., On a supposed Species of Trichina (T. cystica) from the Human Bladder; in his paper on “Parasitic Forms,” in ‘Hay’s Amer. Journ. Med. Sci.,’ 1868, p. 376.—Sanders, R., ‘Edin. Month. Journ.,’ 1853.—Sawer, A., ‘Bost. Med. and Surg. Journ.,’ 1865, p. 16.—Sutton, G., Report on Trichinosis; Indiana, U.S., 1874.—Thudichum, J. W. S., ‘Brit. Med. Journ.,’ Jan., 1864, repr. in ‘Glasgow Med. Journ.,’ April, 1864, p. 116; also letter in ‘Edin. Med. Journ.,’ Feb., 1864.—Idem, “Rep. on the Parasitic Diseases of Quadrupeds used as Food,” pub. by the Med. Officer of the Privy Council, London, 1865.—Idem, “The Diseases of Meat as affecting the Health of the People,” ‘Journ. Soc. of Arts,’ April 20, 1866.—Idem, “German Sausages and the Trichina Disease,” ‘Scientific Opinion’ for April 25, 1866.—Idem, ‘Lancet’ for Jan. 6, 1866, p. 16.—Turner, W., “On the Trichina spiralis,” ‘Edin. Med. Journ.,’ Sept., 1860; in the ‘Year-Book,’ p. 109, for 1860; in ‘Med.-Chir. Rev.,’ 1862; and in ‘Bost. M. and S. Journ.,’ vol. lxiii, p. 294.—Ude, “Rep. on the Inspection of Pigs,” ‘Med. Times and Gaz.,’ Aug., 1868, p. 141.—Valentin, ‘Micr. Journ. and Struct. Rec.,’ 1842, p. 87.—Virchow, R., Extr. from his brochure on ‘Trichina’ (by myself), in ‘Gunther’s Record’ for 1864, p. 611.—Idem, “On the Cure of Trichinosis,” ‘Brit. Med. Journ.,’ April, 1866, p. 368.—Idem, from “Comptes Rendus,” in ‘Qrt. Journ. Micr. Sci.,’ 1861.—Idem, from his ‘Archiv,’ 1860, Bd. xviii, Heft. 4, p. 330; in ‘Brit. and For. Med.-Chir. Rev.,’ vol. xxvi, p. 515, 1860.—Wedl, Report, ‘Brit. Med. Journ.,’ Dec., 1866, p. 618.—Wilks, S., “Letter respecting the Discovery of Trichina,” ‘Lancet,’ March 10, 1866, p. 269; see also the ‘Times,’ Feb. 13, 1866.—Windsor, J., ‘Brit. Med. Journ.,’ March 4, 1866, p. 319.—Wood, H., case, ‘Lond. Med. Gaz.,’ 1835.

Foreign Literature:—Ardenghi, E., “Sulla Trichina spiralis,” ‘Lo Studente Veterinario,’ 1876, p. 115.—Behrens, “Ein Fall von Trichiniasis,” ‘Deutsche Klinik,’ No. 30, 1863 (quoted by Davaine).—Bette, F., ibid., 1876.—Bischoff, ‘Path. Anat. des menschl. Körp.,’ 1845.—Idem, ‘Med. Annalen,’ 1840.—Böhler, ‘Die Trichinenkrankheit in Planen,’ 1863.—Boudin, “Des épidémies de Trichina spiralis observées en Allemagne dans ces dernières années,” ‘Journ. de Méd. Vét. Milit.,’ August and September, 1864 (quoted by Davaine).—Claus, ‘Wurzb. nat. Zeitschr.,’ 1860.—Idem, ‘Ueber die Trichine’ (a discourse), 1877.—Colberg, ‘Deutsche Klinik,’ 1864.—Davaine, C., ‘Traité’ (l. c., Bibl. No. 1), 1860, p. 672, 2nd edit., p 732–768.—Idem, “Faits et Considerations sur la Trichine,” ‘Mémoires de la Société de Biologie’ for the year 1862, tom. iv, ser. 3, 1863; in ‘Gazette Médicale de Paris,’ 1863; in ‘British Medical Journal’ for April 25, 1863; and in my ‘Entozoa,’ p. 349.—Idem, “La Trichine” (popular exposition), in ‘Revue des Deux Mondes’ for May, 1865.—Dujardin (l. c., Bibl. No. 1), p. 24.—Fiedler, ‘Virchow’s Archiv,’ 1864.—Fleckles, F., ‘Die Trichinen und die Trichinenkrankheit’ (popular exposition), Prag., 1866 (quoted by Davaine).—Friedrich, N., ‘Virchow’s Archiv,’ 1862.—Fürstenberg, “Wochenblatt d. Ann. der Landwirthsch., in d. Königl. Preuss. Staaten,” 1865.—Gerlach, C., ‘Die Trichinen,’ 1866.—Idem, ‘Hannöversche Zeitschrift,’ 1864.—Hagen, in ‘Pharmaceutische Centralhalle,’ 1862.—Henle, ‘Muller’s Archiv,’ 1835, s. 526.—Herbst, ‘Nachrichten v. d. Georg-Aug. Univ. zu Göttingen,’ 1852; ‘L’Institut,’ 1852, p. 135.—Heschl, R. L., ‘Ueber Trichinen, die Trichinenkrankheit und die Schützmassregeln dagegen,’ Gratz, 1866 (quoted by Davaine).—Kestner, “Etude sur le Trichina,” ‘Gaz. Méd. de Paris,’ 1864.—Klusemann, “Die Erkrankung durch den Genuss von Nahrungsmittel aus dem Thierreiche,” ‘Deutsche Klinik,’ 1864.—Kobelt, ‘Valentin’s Repertorium,’ 1841.—Krabbe, “Husdyrenes Indvoldsorme,” ‘Tiddsskrift for Vet.,’ 1872.—Kratz, ‘Die Trichinenepidemie zu Hedersleben,’ 1866.—Küchenmeister, ‘Parasiten,’ 1855.—Leuckart, ‘Untersuchungen ueber Trichina spiralis,’ 1866.—Idem, ‘Die mensch. Par.,’ Bd. ii, s. 409.—Idem, “Die neuesten Entdeckungen ueber menschliche Eingeweidewürmer und deren Bedeutung für die Gesundheitspflege,” ‘Unsere Zeit.,’ 1862.—Lion, ‘Zur Geschichte, Therapie, Prophylaxis, und Sanitätspolizei der Trichinen’ (quoted by Pagenstecher).—Luschka, “Zur Naturgeschichte der Trichina spiralis,” ‘Zeitschr. für wissenschaftl. Zool.,’ 1851.—Meissner, ‘Zeitschr. f. rat. Med.,’ 1855.—Idem, “Ueber Trichinenkrankheit,” ‘Schmidt’s Jahrbücher,’ 1863.—Ordonez, E. L., ‘Note sur la Distinction des Sexes et le Développement de la Trichina spiralis des Muscles,’ Paris, 1863; and ‘Compt. Rend. Soc. Biologie,’ p. 61, 1863 (quoted by Davaine).—Pagenstecher, ‘Verhandl. d. Naturhist.-Med. Vereins zu Heidelberg,’ 1864.—Idem (und Fuchs), ‘Die Trichinen,’ 1865.—Perroncito, “La Trichina spiralis” in ‘Italia. Estr. degli Annali R. Accad. d’Agric. di Torino,’ vol. xx, 1877.—Reyher, O., ‘Die Trichinenkrankheit,’ Leipzig, 1862.—Rodet, H., ‘De la Trichine et de la Trichinose,’ Paris, 1865 (quoted by Davaine).—Rupprecht, B., ‘Die Trichinenkrankheit im Spiegel der Hettstedter Endemie betrachtet,’ Hettstedt, 1864.—Seidel, ‘Jenaische Zeitschr. f. Med. u. Nat.’ 1864.—Siebert, ‘Ueber die Trichinenkrankheit und ihre Vermeidung,’ Jena, 1863.—Siebold, art. “Parasiten,” ‘Wagner’s Handwörterbuch,’ 1844.—Simon, G., “Eine Trichinen-epidemic in Calbe,” ‘Preussische Medicinal Zeitung,’ 1862.—Tommasi, ‘La Trichina spiralis e la Malattia prodotta da esso,’ Torino, 1863.—Tüngel, ‘Archiv von Virchow,’ xxvii, 3, 421, 1863 (quoted by Davaine).—Virchow, ‘Deutsche Klinik,’ 1859; ‘Comptes Rendus de l’Acad. des Sci.,’ tom. xlix.—Idem, ‘Archiv f. Path. Anat. und Physiol.,’ Bd. xviii.—Idem, ‘Darstellung der Lehre von den Trichinen’ (fur Laien und Aerzte), 1864.—Vogel, ‘Die Trichinenkrankheit,’ 1864.—Wagner, “Eine Trichinenepidemie in Leipzig,” ‘Arch. der Heilkunde,’ 1864.—Wunderlich, C. A., “Sur la diagnose probable de l’affection trichinale,” ‘Gaz. Méd. de Paris,’ p. 311, 1863; from ‘Wagner’s Archiv der Heilkunde,’ ii, 3, p. 269, Leipzig, 1861 (quoted by Davaine).—Zenker, “Zur Lehre von der Trichinenkrankheit,” ‘Deutsches Archiv. für Klin. Med.,’ Bd. viii, s. 387.—Idem, ‘Virchow’s Archiv,’ 1855 and 1860.

Trichocephalus dispar, Rudolphi.—This well-known worm possesses a long filiform neck, occupying about two thirds of the entire length of the body. The surface of the skin though smooth to the naked eye is furnished on one side with a longitudinal band of minute wart-like papillæ. The tail of the male is curved, and emits at the extremity a short, tubular penis-sheath, armed with minute retroverted spines. The tail of the female is straight and bluntly pointed. The eggs measure 1/480″ to 1/447″ in their long diameter. The whipworm infests the cæcum, and also the upper part of the colon. Upwards of one thousand were found by Rudolphi in a woman.

The original name of Trichuris, given to this worm by Buttner, could not, of course, be allowed to stand when it became evident that the so-called tail was in reality the head and neck. The Trichocephalus is not uncommon in England and Ireland. It is less frequent in Scotland. On the continent, however, it is so abundant that M. Davaine calculates that not less than one half of the inhabitants of Paris are infested by it. From what Dujardin has said it can be scarcely less abundant in Northern France, for M. Duval, the distinguished director of the Rennes School of Medicine, supplied that helminthologist with numerous specimens on various occasions. The worm abounds in Italy and Egypt; being scarcely less prevalent in the United States. The lamented Mr Noel, one of my old pupils at the Middlesex Hospital College, brought me specimens which he found post-mortem on three or four occasions. Dr Haldane, of Edinburgh, once or twice obtained large numbers (post-mortem). In Ireland, Bellingham found the worm in eighty-one out of ninety post-mortem examinations. Mr Cooper, of Greenwich, met with it, post-mortem, in eleven out of sixteen instances. When treating patients for tapeworm I have repeatedly expelled the whipworm.