David Bruce (British parasitologist)
(b. Melbourne, Australia, 29 May 1855; d. London, England, 27 November 1931)
Sir David Bruce won renown for discovering the bacterial cause of Malta fever and for extensive and fruitful researches on trypanosomiasis. His professional life was spent in the Army Medical Service and the Royal Army Medical Corps, in which he attained the special rank of surgeon general.
Bruce was the only son of Scottish parents who emigrated to Australia during the gold rush of the early 1850’s. His father, David Bruce, accompanied by his wife, Jane Hamilton, left Edinburgh to install a crushing plant in a Victoria goldfield. When he was five years old, David’s parents returned with him to Scotland and settled in Stirling. He attended high school until the age of fourteen, and then worked for a warehouse firm in Manchester. His ambition to become a professional athlete, for which his great physique fitted him, was frustrated by an attack of pneumonia at age seventeen. He resumed his studies, and in 1876 gained admission to the University of Edinburgh.
As a schoolboy, Bruce became an enthusiastic ornithologist and planned a university course in zoology. After he had completed his first year at Edinburgh as medalist in natural history, a physician friend persuaded him to study medicine. After graduating M.B., C.M. in 1881, he assisted a doctor in Reigate, where he met Mary Elizabeth Steele, six years his senior, daughter of the previous owner of the practice. They were married in 1883. Although childless, their marriage was singularly fortunate, for Mary Bruce proved an indispensable helpmate—domestically, socially, and scientifically.
Bruce found general practice uncongenial, and in August 1883 was commissioned surgeon captain in the Army Medical Service. The following year, he was posted to Malta, where he and his wife were quartered in the Valetta Hospital, which had no facilities for research. Impressed by Koch’s recent discovery of the tubercle bacillus, Bruce decided to investigate Malta fever, which annually hospitalized around a hundred soldiers of the British garrison, for an average of three months. He purchased a microscope, and late in 1886 he found “enormous numbers of single micrococci” in the spleen of a fatally ill patient. Splenic pulp from four later patients, inoculated into Koch’s nutrient agar, yielded cultures of a slowly growing “micrococcus.” Bruce reported these findings in September 1887. Subsequent publications described further properties of the organism, for which he proposed the name Micrococcus melitensis. Its bacillary morphology was unrecognized until Bang isolated Bacillus abortus in 1897. In 1920, on the suggestion of Feusier and Meyer, the generic term Brucella was adopted for these closely related microorganisms. The epidemiology of the disease remained a mystery until 1905, when T. Zammit, a Maltese member of the Commission for the Investigation of Mediterranean Fever, the twelve-man team of experts headed by Bruce, implicated goat’s milk as the disseminating vehicle. The disease was conquered when goat’s milk was eliminated from the diet of the Malta garrison. The eponymous term “brucellosis” has now replaced such names as Malta, Mediterranean, and undulant fever.
Between these two phases of his work in Malta, Bruce had become famous for trypanosomiasis researches in Zululand and Uganda. After departing from Malta in 1889, he spent his leave discoursing in Koch’s laboratory while his wife acquired the latest techniques in microscopy, staining, and media making. He then taught pathology at the Army Medical School at Netley, introducing the experimental attitudes and bacteriological methods of Pasteur, Lister, and Koch. In 1894 Bruce was posted to Natal, whose governor (a former lieutenant governor of Malta) asked him to investigate an epizootic, nagana, that was affecting cattle in northern Zululand.
After trekking for five weeks by ox wagon, the Bruces arrived at Ubombo, where they lived for two months in a wattle-and-daub hut, using the veranda as a laboratory. Bacteriological examinations of affected oxen proved negative; but intensive microscopic study of blood specimens revealed a motile, vibrating hematozoon, which Bruce later concluded was a trypanosome. The relationship of this parasite to nagana was demonstrated by inoculating blood from infected cattle into healthy horses and dogs: they became acutely ill, and their blood swarmed with hematozoa. The natural mode of transmission of the disease was revealed, as Bruce explained in his Croonian lectures (1915), when two oxen and several dogs, sent into a low-lying “fly belt” for a fortnight, acquired this same parasite in their blood. He was now convinced that nagana was identical with the “tsetse fly disease” described by Livingstone in 1858, and that this fly transmitted the causal trypanosome.
Recalled temporarily to Natal, the Bruces returned in September 1895 to their isolated hut in the Zululand bush and stayed almost two years. Bruce’s Preliminary Report was published in December 1895 and was followed early in 1897 by his Further Report. These classic documents described the hematozoa of nagana, established the tsetse fly Glossina morsitans as the vector, and implicated regional wild game, such as antelope and buffalo (themselves immune and unaffected), as the trypanosomal reservoir. Living trypanosome samples were forwarded to the Royal Society, which in 1899 elected Bruce a fellow and published a paper by Plimmer and Bradford characterizing the parasite and naming it Trypanosoma brucei.
During the Boer War, Bruce distinguished himself at the siege of Ladysmith, where he directed a hospital and performed successful surgery. Mary Bruce received the Royal Red Cross for devoted work with the wounded, particularly as nursing sister in her husband’s operating theater. They returned home in October 1901.
In 1903 Bruce was chosen to head the Royal Society’s Sleeping Sickness Commission to Uganda. On behalf of the Foreign Office and at Patrick Manson’s urging, the Society had organized a similar commission to investigate an epidemic in Uganda in 1902, but its activities were uncoordinated and two members had returned home. The Bruces reached Entebbe in March 1903, with Dr. David Nabarro and a sergeant technician, and met the remaining representative of the first commission, a young bacteriologist, Dr. Aldo Castellani.
Manson’s tentative suggestion of Filaria perstans as the causal agent had proved untenable; but Castellani had recently noted trypanosomes in cerebrospinal fluid taken from five victims. Previously, he had grown streptococci from the cerebrospinal fluid and heart blood of more than thirty. Well aware of the potential significance of the trypanosomes, although perturbed at the conflicting evidence, Castellani did not wish to be ridiculed by Bruce, still less by Nabarro, who was little older than he and whose appointment to supersede him he resented. He therefore imparted his observations to Bruce, on condition that he (Castellani) should temporarily continue searching for trypanosomes, that he should then publish his findings as sole author, and that Nabarro should not be informed. When Castellani left Entebbe three weeks later, he had demonstrated trypanosomes in twenty additional cases. He had also taught Bruce the techniques of lumbar puncture and of examining the cerebrospinal fluid for trypanosomes.
In 1902 Dutton had reported Trypanosoma gambiense in the blood of a febrile Englishman in Gambia and in 1903 Baker had diagnosed similar cases of trypanosome fever in Uganda, but no connection between these conditions and Uganda sleeping sickness was then suspected. At first Bruce appeared skeptical about trypanosomes as causal agents of human sleeping sickness, but soon after Castellani’s departure Bruce and Nabarro amassed convincing evidence that this disease was caused by T. gambiense inoculated by the tsetse fly Glossina palpalis. Bruce returned to England in August 1903. The “Progress Report” by himself and Nabarro, sent from Entebbe, acknowledged Castellani’s discovery; but the “Further Report,” written by Bruce, Nabarro, and E. D. W. Greig, betrays a changed attitude that encouraged his supporters, particularly the zoologist Ray Lankester, to minimize Castellani’s contribution. The resulting dispute broke into print intermittently for several years. Despite Nabarro’s magnanimous support of Castellani, most subsequent accounts displayed bias, which J. N. P. Davies’ carefully documented articles (1962, 1968) should help to correct.
From 1908 to 1910, Bruce rejoined the Royal Society’s continuing commission in Uganda, where he directed researches into conditions governing the transmissibility of T. gambiense by Glossina palpalis, and studied cattle and game as potential reservoirs of the parasite. In 1911, he was appointed director of another Sleeping Sickness Commission, to investigate trypanosomiasis in Nyasaland. During the next two years, T. rhodesiense was identified as the main regional pathogen and Glossina morsitans as its vector; and certain other trypanosomal species pathogenic to domestic animals were characterized. The commission concluded that T. rhodesiense and T. brucei were identical, but this view was disputed by contemporary German authorities and now has no adherents.
From 1914 until he retired in 1919, Bruce was commandant of the Royal Army Medical College. During the war, his administrative abilities were fully utilized, especially as director of scientific research and as chairman of committees for the study of tetanus and trench fever. In his last years, Bruce suffered recurrent lung infections and wintered in Madeira. He died of cancer in his seventy-seventh year. His wife, who accompanied her husband on all his arduous trips, working self-effacingly beside him as technician, microscopist, and draftswoman, predeceased him by four days. On his deathbed, Bruce requested that her outstanding assistance should always be emphasized in any biographical account of him.
Bruce’s many distinctions included fellowship in the Royal Society and the Royal College of Physicians of London; honorary doctorates from the universities of Glasgow, Liverpool, Dublin, and Toronto; honorary memberships in several foreign academies and societies; and numerous medals of honor. He was appointed C.B. in 1905, knighted in 1908, and made K.C.B. in 1918. His abrupt manner, blunt speech, and egotistical personality endeared him to few; but his great energies and talents were dedicated to mankind’s health and welfare, and he died poor. Moreover, he had vision and compassion, as shown in this closing passage from his presidential address, “Prevention of Disease,” to the British Association, meeting at Toronto in 1924:
We are all children of one Father. The advance of knowledge in the causation and prevention of disease is not for the benefit of any one country, but for all—for the lonely African native, deserted by his tribe, dying in the jungle of sleeping sickness, or the Indian or Chinese coolie dying miserably of beri-beri, just as much as for the citizens of our own towns.
I. Original Works. Bruce’s major works are “Note on the Discovery of a Microorganism in Malta Fever,” in practitioner, 39 (1887), 161–170; “The Micrococcus of Malta Fever,” ibid., 40 (1888), 241–249; Preliminary Report on the Tsetse Fly Disease or Nagana in Zululand (Durban, 1895); Further Report on the Tsetse Fly Disease or Nagana in Zululand (London, 1897); “Progress Report on Sleeping Sickness in Uganda,” in Reports of the Sleeping Sickness Commission of the Royal Society, 1 (1903), 11–88, written with David Nabarro; “Further Report on Sleeping Sickness in Uganda,” ibid., 4 (1903), 1–87, written with D. Nabarro and E. D. W. Greig; “The Development of Trypanosoma gambiense in Glssina palpalis,” in Proceedings of the Royal Society, 81B (1909), 405–414, written with A. E. Hamerton, H. R. Bateman, and F. P. Mackie; “The Morphology of the Trypanosome Causing Disease in Man in Nyasaland,” ibid., 85 (1912), 423–433, written with D. Harvey, A. E. Hamerton, J. B. Davey, and Lady Bruce; “Trypanosomes Causing Disease in Man and Domestic Animals in Central Africa” (the Croonian lectures), in Lancet (1915), 1 , 1323–1330; (1915), 2 , 1–6, 55–63, 109–115; and “Prevention of Disease,” in Science, 60 (1924), 109–124.
II. Secondary Literature. Unsigned obituaries of Bruce are “Sir David Bruce, K.C.B., M. D. Edin., F.R.S.,” in Lancet (1931), 2 , 1270–1271; and “Major-General Sir David Bruce, K.C.B., LL.D., D.Sc., F.R.C.P., F.R.S.,” in Journal of the Royal Army Medical Corps, 58 (1932), 1–4. Signed ones are J. R. Bradford, “Sir David Bruce—1855–1931,” in Obituary Notices of Fellows of the Royal Society, 1 (1932), 79–85; S. R. Christophers, “Bruce, Sir David (1855–1931),” in Dictionary of National Biography 1931–1940, pp. 108–110; A. E. Hamerton, “Major-General Sir David Bruce, K.C.B., D.Sc., LL.D., F.R.C.P., F.R.S., Late A.M.S.,” in Transactions of the Royal Society of Tropical Medicine and Hygiene, 25 (1931–1932), 305–312; D.W.T. and W.J.T., “Major-General Sir David Bruce, K.C.B., F.R.S.,” in Nature., 129 (1932), 84–86; and C. M. Wenyon, “Major-General Sir David Bruce, K.C.B., F.R.S.,” ibid., 86–88.
Further information on Bruce’s work can be found in M. T. Ashcroft, “A Critical Review of the Epidemiology of Human Trypanosomiasis in Africa,” in Tropical Disease Bulletin, 56 (1959), 1073–1093; Aldo Castellani, “On the Discovery of a Species of Trypanosoma in the Cerebrospinal Fluid of Cases of Sleeping Sickness,” in Proceedings of the Royal Society, 71 (1902–1903), 501–508; J. N. P. Davies, “The Cause of Sleeping Sickness? Part II,” in East African Medical Journal, 39 (1962), 145–160, and “Informed Speculation on the Cause of Sleeping Sickness 1898–1903,” in Medical History, 12 (1968), 200–204; E. R. Lankester, “Nature’s Revenges: The Sleeping Sickness,” in The Kingdom of Man (London, 1907), pp. 159–191; Reports of the Commission Appointed by the Admiralty, the War Office, and the Civil Government of Malta for the Investigation of Mediterranean Fever, Under the Supervision of an Advisory Committee of the Royal Society, 7 pts. in l vol. (London, 1905–1907); Reports of the Sleeping Sickness Commission, Royal Society, Nos. 1–11 (London, 1903–1911); and C. Wilcocks, “Trypanosomiasis,” in Aspects of Medical Investigation in Africa (London, 1962), pp. 59–90.
There is also enlightening correspondence. Two collections of letters are those of Bruce, in the library of the Royal Society of Tropical Medicine and Hygiene, London, and those of R. U. Moffat, former principal medical officer for Uganda, in Makerere College Library, Kampala. Individual letters are Aldo Castellani, “… The Exact History of how Colonel Bruce was Acquainted With My Observations….,” in The Times, 8 July 1908, p. 18; E. Ray Lankester, in The Times, 19 Nov. 1903, p. 2, and 14 Aug. 1913, p. 4; and in British Medical Journal, 11 Aug. 1917, p. 198, and 17 Sept. 1917, pp. 402–403; and David Nabarro, in Journal of Tropical Medicine and Hygiene, 15 July 1908, pp. 224–225; The Times, 22 Sept. 1913, p. 21; and British Medical Journal, 15 Sept. 1917, pp. 374–375, and 6 Oct. 1917, pp. 467–468.
Claude E. Dolman
The Australian parasitologist David Bruce (1855-1931) discovered the causes of Malta, or undulant, fever and of sleeping sickness.
David Bruce was born on May 29, 1855, in Melbourne, Australia. His family went to Scotland when David was 5. He attended the medical school at Edinburgh University. In 1883 he married Mary Elizabeth Steele, who assisted him in his work throughout his life. Shortly thereafter Bruce was commissioned in the Royal Medical Service and was posted to Malta in 1884. There he studied a serious, often fatal disease, known as Malta or Mediterranean fever, which was prevalent among civilians and military personnel.
Malta fever is characterized by a continuous long-lasting fever which rises and falls irregularly, and which has been known in the Mediterranean region since the time of Hippocrates, who accurately described it. Within two years of his arrival in Malta, Bruce found a bacterium in the spleen of a number of fatal human cases of the disease. He named the organism Micrococcus melitensis because of its small size. He also found that human beings became infected from goats' milk and cheese and that abortions were common in diseased goats as well as in pregnant women who contracted the fever. This and later work led eventually to the eradication of the disease.
In 1894 Bruce went to Zululand, South Africa, where he studied nagana, a common disease of domestic animals. By 1895 he discovered trypanosomes, minute wormlike protozoans, living in the blood of sick cattle, and he showed that this parasite was transmitted by the bite of the tsetse fly. He had actually found a mixture of three species, which are now identified as Trypanosoma brucei (named after him), T. congolense, and T. vivax. Bruce's work was with animals at that time, and he was not directly concerned with human disease; but in 1890 trypanosomes were found in human blood and in 1901 were named T. gambiense.
A mysterious lethargy that had long been known in regions of tropical Africa first began to attract considerable attention when slaves exported to the West Indies often developed this disease. In Uganda alone in 1900, about two-thirds of the population died from it; they called it sleeping sickness. In 1902 the Royal Society sent a Sleeping Sickness Commission to Uganda, and one of its members, Aldo Castellani, reported finding trypanosomes in the cerebrospinal fluid of a patient. The following year a second commission was dispatched, with Bruce at its head. Following Castellani's lead and aided by his experience with nagana, Bruce proved that trypanosomes, transmitted by the tsetse fly, were the cause of sleeping sickness. Bruce was engaged in sleeping sickness investigations until 1911, when he was posted to the Royal Army Medical College, where during World War I he directed research on louse-carried trench fever and tetanus. He retired in 1919; he died on Nov. 20, 1931, in London.
There is no book-length biography of Bruce. Frederick Eberson, Man against Microbes: The Story of Preventive Medicine (1963), gives an account of Bruce's work in combating trypanosomiasis. Paul de Kruif's popular Men against Death (1932) offers an interesting account of Bruce's role in the scientific battle against Malta fever. □
British physician and pathologist who is best known for his landmark studies of parasitology, especially sleeping-sickness. In 1887, Bruce reported that a bacterial agent causes Malta fever. His studies of nagana, a disease of domestic animals in South Africa, showed that the disease was transmitted by the bite of an infected tsetse fly. This insight led to his discovery that sleeping sickness (a disease of humans that is caused by a microbial agent known as a trypanosome) was also transmitted by the tsetse fly.