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Item Comparative pathogenicity of Trypanosoma brucei rhodesiense strains in Swiss white mice and Mastomys natalensis rats(Kenya Agricultural Research Institute, 1927) Muchiri, M.W.; Ndung'u, K.; Kibugu, J.K.; Thuita, J.K.; Gitonga, P.K.; Ngae, G.N.; Mdachi, R.E.; Kagira, J.M.; Kenya Agricultural and Livestock Research Organization (KALRO), Biotechnology Research Institute (BioRI), P. O. Box 362, Kikuyu, Кепуа; Jomo Kenyatta University of Agriculture and Technology, P.O. Box 62000-00200, Kenya; Kenya Food Crop Research Institute, P. O. Box 30148, Nairobi, KenyaWe evaluated Mastomys natelensis rat as an animal model for Rhodesian sleeping sickness, Parasitaemia, clinical and pathological characteristics induced by T. b. rhodesiense isolates, KETRI 3439, 3622 and 3637 were compared in Mastomys rats and Swiss white mice. Each isolate was intra-peritonially injected in mice and rat groups (n-12) at 1x 10º trypanosomes/0.2 ml. Pre-patent period (PP) range for KETRI 3439 and KETRI 3622-groups was 3-6 days for mice and 4-5 days for rats while for KETRI 3637-infected mice. and rats was 5-9 and 4-12 days, respectively. Pairwise comparison between PP of mice and rats separately infected with either isolate showed no significant difference (p>0.05). The PP's of KETRI 3637-infected mice were significantly (p>0.01) longer than those infected with KETRI 3439 or KETRI 3622, a trend also observed in rats. The second parasitaemic wave was more prominent in mice. Clinical signs included body weakness, dyspnoea, peri-orbital oedema and extreme emaciation which were more common in rats. Survival time for KETRI 3439 and 3622-infected groups was significantly (p<0.05) longer in mice than rats but similar in KETRI 3637-infected groups. Inflammatory lesions were more severe in rats than mice. All mice and KETRI 3622-infected rats had splenomegaly, organ congestion with rats additionally showing prominent lymphadenopathy. KETRI 3439-infected rats showed hemorrhagic pneumonia, enteritis with moderate splenomegaly and lymphadenopathy. KETRI 3637-infected rats had the most severe lesions characterized by prominent splenomegaly, lymphadenopathy, hepatomegaly, enlarged adrenal glands, organ congestion, generalized oedemas, gastroenteritis, pneumonia and brain congestion. KETRI 3637- infected Mastomys is a suitable model for studying pathophysiology of HAT.Item Protection from Mosquito Bites in Outdoor Gatherings(1936) Ginsberg, M. J.; Rutgers UniversityThe problem of temporarily ridding a small area of adult mosquitoes where a large number of people could comfortably enjoy a summer evening has often presented itself. Such places may vary in area from a few square yards to several acres, and may consist of a well-cared for lawn shrubs flowers trees and other valuable vegetation which must not be injured. It is obvious that in order to eliminate mosquitoes the area must be treated in such a way those on the wing or resting on the grass within the area are killed or incapacitated. While those outside of the treated area are repelled.Item "Zoonoses in East Africa" May 1956(1956) Willett, K.C.; East African Trypanosomiasis ResearchIN the report of the recent conference in Kampala, Uganda, "Zoonoses in East Africa"" I was quoted as suggesting that Trypanosoma rhodesiense had (developed from Tr. brucei by repeated passages through Glossina pallidipes. My thesis was, in fact, almost the exact opposite of this. I emphasized that all the evidence so far shows that the property of infectivity to man which alone distinguishes Tr. rhodesiense from Tr. brucei is an extremely stable one and that there has never been a known case of interconversion of these two. On the other hand, I pointed out, in any area where Tr. rhodesiense had appeared, either it could be traced to direct introduction by infected human beings from a known source, or the other human infective 'species', Tr. gambiense, had been known to be present in the area for some time.Item Some of the Protozoological Problems of African Human Trypanosomiasis(1956) Willet, K.C.; Trypanosomiasis Research Institute SalisburyIt is clearly impossible in the short span of fifteen minutes to cover more than a very small part of the large subject of the protozoology of trypanosome infections and I have therefore so chosen my title as to impose three important limitations: the first that my remarks are restricted to the pathogenic trypanosomes of Africa: the second that I am concerned only with those related to human sleeping sickness, and the third that I make no claim to consider more than a few of the problems which seem to me, personally, to be of importance.Item The Local Reaction in Man at the Site of Infection with Trypanosoma Rhodesiense(1957) Fairbairn, H.; Godfrey, D.G.; West Africa Institute of Trypanosomiasis ResearchA problem of great importance in trypanosomiasis is what happens to the metacyclic trypanosomes when they are injected into a mammal by the bite of an infected tsetse-fly. Gordon and Willett (1956) infected guinea-pigs by the bites of tsetse-flies cyclically infected with Trypanosoma rhodesiense. By the subinoculation of heart blood into rats they showed that the blood of the guinea-pigs was infective 5 minutes, 45 minutes, 4! hours and 24 hours after the infective bite. In a fresh preparation made from the site of the bite within five minutes of its infliction, a single trypanosome was seen; and ground-up tissue, removed from the bitten area within 45 minutes of the infective feed, successfully infected white rats on two occasions. The only occasion on which they found trypanosomes on sectioning the site of bite was immediately after a fly had probed but not fed. They postulated that in guinea-pigs the majority of the metacyclic forms of T. rhodesiense deposited by the feeding tsetse rapidly migrated or were carried away from the site of the bite; that a proportion of these trypanosomes or their descendants reached the general circulation within a few hours, or sometimes within a few minutes, of the infective bite; and that, once the trypanosomes reached the circulation, they persisted in the blood throughout the incubation-period. Their guinea-pigs, however, still had an incubation-period of 7-10 days before trypanosomes were found microscopically in the blood.Item Titres of The Igm Class of Immunoglobulins In Gambian Sleeping Sickness and Other Disease Conditions(1961/1962) Watson, H.J.C.; Chirieleison, G.; Nigerian Institute of Trypanosomiasis Research KadunaThe work of Mattern et al. (1961) and Mattern (1962) has demonstrated that raised levels of the IgM class of immunoglobulins which occur in human trypanosomiasis provide a valuable means for the presumptive diagnosis of the disease. In considering the use of this technique, it is obviously of importance that information should be available on the IgM titres occurring in other pathological conditions which might complicate or confuse its application. This paper describes findings in patients with Gambian trypanosomiasis, both before and after they had been treated, and in a variety of other conditions.Item The Antigenic Character of the 'Brucei' Trypanosomes(1962) Brown, K.N.The causative agents of 'sleeping sickness' are two trypanosome species of the brucei sub-group, Hoare (1957), namely Trypanosoma rhodesiense and T. gambiense. The disease especially that due to T. gambiense, is typically chronic, lasting several months or years with the intermittent appearance of parasites in the blood. Ultimately the trypanosomes invade the central nervous system with the subsequent onset of 'sleeping'.Item Chemotherapy of African Trypanosomiasis(1962) Robertson, D.H.H; EATRO (East African Trypanosomiasis Research Organization Tororo Uganda)BEFORE deciding which drug to luse in any patient with trypanosomiasis it is necessary to determine by examination of the cerebrospinal fluid (e.S.F.) whether the central nervous system is involved. The Sicard-Cantaloube method for estimating C.S.F. protein is convenient for use in the field (Willett, 1955): if a sample contains more than 25 mg. of protein per 100 mI., more than 5 leucocytes per c.mm., or if trypanosomes are found during the examination of the C.S.F. in the Fuchs-Rosenthal cytometer, then the patient will require mel B. Pentamidine or suramin should only be used during the early stage of the disease before central nervous system invasion has occurred.Item The Occurrence of Human Trypanosomiasis among the Rukuba Tribe of Northern Nigeria(1962) Duggan, A.J.; Wellcome Museum of Medical Science London , Sleeping Sickness Service NigeriaAn account is given of an outbreak of sleeping sickness, caused by Trypanosoma gambiense, that occurred in 1931-45 among the Rukuba people of Northern Nigeria, to illustrate the effect of local customs on epidemiology. The history of the tribe is reviewed, relevant tribal customs and the topography and climate of the area are described and the course of the epidemic is traced. Glossina palpalis (R.-D.) inhabited the dense vegetation of the escarpments, and when the cessation of local wars allowed the people to leave over-crowded fortified hill-top villages for the more wooded edge of the escarpment, contact with the fly became much closer. In 1931 and 1932, men who farmed seasonally in Zaria Province returned harbouring trypanosomes and developed sleeping sickness. Infection was being acquired locally by 1933, and the outbreak gained impetus in 1934 because the men spent long periods in tsetse-infested groves during septennial initiation rites. Tsetse spread from the groves along the shaded streams that supplied water and into the compounds along the hedges originally planted for defence. Sleeping sickness brought the tribe to the verge of extinction. Mass treatment of the population failed to stop transmission, which continued until, by a combination of ruthless and discriminative clearing instituted in January-April 1944, G. palpalis was practically eradicated from the streams and groves of the two main areas and from selected foci in a third. This was achieved in the first year, and the first two areas were completely freed of fly by residual clearing in the dry season of 1945. As a result of this and mass treatment of the population there has been no evidence of indigenous transmission in these two areas since. In the third area, which is separated from the main ones by a watershed, small numbers of infections continued, and a small focus of G. palpalis was discovered and eliminated by clearing in 1953; although a few foci of the fly may remain, the occasional outbreaks of the disease that occur are completely controlled by repeated survey followed by mass treatment.Item A Comparative study of the Epidemiology of Endemic Rhodesian Sleeping Sickness in different parts of Africa(1963) Apted, F.I.C.; Ormerod, W.E.; Smyly, D.P.; Stronach, B.W.; Szlamp, E.L.; Bureau of Hygiene and Tropical Diseases, Tanganyika, London School of Hygiene and Tropical Medicine, Southern Rhodesia, Game Ranger TanzaniaIn a history of Rhodesian sleeping sickness ORMEROD [this Bulletin, 1962, v. 59, 339] has suggested that the disease arose from a single focus in the Zambezi area and spread northwards in epidemics which left residual foci behind them. The present work was done to study the epidemiological conditions in 4 areas: -The Zambezi river system, where the disease was first recognized but no epidemic occurred; Ngamiland, where cases have recently become more numerous; and 2 areas in Tanganyika which had a big epidemic in 1928-32. In the Gokwe District of Southern Rhodesia (Zambezi area) 5 cases have occurred in the last 20 years, and they have been relatively chronic and sporadic. In Ngamiland, the disease is increasing and 248 cases were diagnosed in 1957-60. The disease, however, is relatively chronic, so that some cases might almost be considered as "healthy carriers", and there is little tendency for it to become epidemic. In the Kahama and Tabora districts of Tanganyika there was an epidemic in 1928, and in 1939; in 1957-59 84 cases occurred. In this area the cases occur at particular foci and the disease is acute. The occupations specially exposed to risk are honey-gathering, cultivation in the bush, and fishing, all of which take men into contact with fly. In the Kasulu district of Tanganyika, there was an epidemic in 1930-32 and another in 1957-60 with 244 cases. The disease was acute and widespread and it affected mainly travellers and those collecting firewood or honey in the bush. Several kinds of game can maintain infection with Trypanosoma rhodesiense, but owing to their habits and habitats most of them do not come into close contact with men and so they are unimportant. The animal which is most likely to act as a reservoir of infection is the bush-buck; it remains in a limited area and returns to its habitat even when disturbed; it often lives near men; it tolerates T. rhodesiense for long periods and on one occasion T. rhodesiense has been isolated from a wild bush-buck [HEISCH et al., ibid., 1959, v. 56, 698]. T. rhodesiense infection of men is most likely to occur when there is sustained triple contact of man, fly and bush-buck (or other game). Glossina pallidipes is the most effective vector because it stays mostly in one small area; G. morsitans is less effective because it ranges more widely, but if infection builds up to a certain level, then G. morsitans readily spreads an epidemic. If this triple contact can be effectively broken, then epidemics can be controlled and prevented.Item Human Trypanosomiasis in South-East Uganda(1963) Robertson, D.H.H. Baker, J. R. ; East African Trypanosomias Research Tororo UgandaDuring the past two decades there has been an increase in the incidence and spread of sleeping-sickness due to Trypanosoma rhodesiense throughout the north-eastern shore area of Lake Victoria; this increase has been associated with heightened fishing activity and increasing and irregular settlement of the tsetse-fly belt of south-east Uganda. The author describes a number of epidemiological factors affecting the occurrence of the disease among fishermen, placing emphasi~ on the correct development of the local fishing industry to avoid, on the one hand, depleting the fish population and, on the other, increasing the incidence of sleeping-sickness. Sociological factors which militate against the development of settlement in Glossinainfested areas of south-east Uganda are also described and plans for future settlement in that area are discussed.Item A Trial of Mel Win the Treatment of Trypanosoma Rhodesiense Sleeping Sickness(1963) Robertson D.H.H; East African Trypanosomiasis Research Organization Tororo UgandaMel W, a water-soluble analogue of melarsoprol, gave promising initial results in the treatment of T. gambiense sleeping sickness. These authors considered Mel W to be less toxic than melarsoprol and since it could also be given by intramuscular (1M) injection, it was thought to have distinct advantages. This paper presents the results of the treatment with Mel W in 17 cases of T. rhodesiense meningo-encephalitis. Large doses of Mel W were tried in a patient (Case No. 261) infected with a melarsoprol-resistant strain of T. rhodesiense.Item The Epidemiology and Control of Human Trypanosomiasis in Glossina Morsitans Fly-Belts(1963) Van D. B; Lambrecht F. L; Department of Agriculture UgandaThe prevalence of infections with Trypanosoma gambiense has fallen by about three-quarters in the last decade, but that of T. rhodesiense has remained steady. Fly control has become very efficient against Glossina palpalis but is often disappointing against G. morsitans. This paper reviews the epidemiology of trypanosomiasis, particularly in savannah areas, and contributes original observations of the authors. The relationship of the 3 trypanosomes of the T. brucei group is considered. Study of the ecology of T. gambiense suggests that it remains confined to forest because it does produce a potent infection in animals and because of the behaviour of its vector. T. rhodesiense can infect animals and can infect G. palpalis [this Bulletin, 1961, v. 58, 1117], and there is a danger that it may invade forest belts. Food is believed to be the dominant factor in the ecology of the fly, and examples show how modifications of the wild animal population or of the vegetation may cause T. rhodesiense infection to flare up. The distribution of tsetse is determined by the tolerance of the larval and pupal stages to environmental conditions, and by the presence of suitable animal hosts for the adult. Methods of control are considered, and it is urged that this should avoid upsetting the natural resources and soil conservation principles of the area. In discussing land use the authors point out that most African soils are not rich enough for sustained agriculture. On marginal land game cropping will give a better return than cattle which are ill-adapted to the environment [ibid., 1960, v. 57, 229], Wild life conservation should be integrated in the development plans of savannah areas. The future of tsetse control lies in zoning of fly belts with sectional clearing and development of certain zones. Interesting suggestions are made for control in the immediate future and in methods of fly survey. Finally, a plea is made for a regional approach to trypanosomiasis control, and for international sponsorship of an inter-African council to integrate fly control in development plans and to secure co-ordination at both national and inter-territorial levels. The organization of research is also discussed.Item Royal Entomological Society of London(1963) Mattingly, P.F.The battle against malaria in Africa has resulted in virtual stalemate. Bot sides are currently regrouping their forces. An account will be given of a visit to some parts of the battlefield (East Africa, Zanzibar, Pemba, Madagascar, Mauritius, S. Rhodesia, Congo, Cameroon, Nigeria) and this will be illustrated by the transparencies. Among the factors to be considered are problems of infraspecific taxonomy behavior and general ecology. These will be discussed.Item The Treatment of Sleeping Sickness (Mainly Due To Trypanosoma Rhodesiense) With Melarsoprol(1963) Robertson, D.H.H.; East African Trypanosomiasis Research Organization Tororo UgandaMelarsoprol was found to be effective in the treatment of T. gambiense meningo-encephalitis later its value was demonstrated in patients with tryparsamide-resistant T. gambiense infections as well as in those with T. rhodesiense meningo-encephalitis who were always incurable before the advent of melarsoprol. Earlier trials with melarsoprol emphasized its toxicity and there was a high mortality (more than 10 per cent.) associated with its use.Item The survival of Toxoplasma in infected mosquitoes(1966) Jennifer, M.C.; Ormerod, W.E.; Department of Parasitology, London School of Hygiene and Tropical Medicine, London1. An incomplete field study in Lincolnshire, England, suggested that toxoplasmosis might be transmitted from pig to man by mosquitoes. Although the results were inconclusive they suggested the experimental work recorded in this paper.2. Trophozoites of the Beverley strain were obtained in increased yield from the peritoneal fluid of Mastomys treated with hydrocortisone. Cysts were obtained in increased yield by passage of the brain of Sigmodon into laboratory mice.3. Four species of mosquitoes were fed through a membrane or on sucrose solution on media containing either cysts or trophozoites of Toxoplasma gondii. In some experiments blood was added to ensure passage of the feed to the mosquito stomach, in others it was excluded so that at least part would pass to the crop.4. A spurious ‘cyst’ resembling but distinguishable from Toxoplasma was noted in the homogenate of mouse brain.5. In no instance did mosquitoes retain infectivity as demonstrated by injection into mice, beyond the third day, but since experiments were not carried on beyond the fourteenth day the existence of an occult form cannot be excluded.Item The Estimation of IgM Immunoglobulin in Dried Blood, For Use as a Screening Test in the Diagnosis of Human Trypanosomiasis In Africa(1967) Cunningham, M. P.; Bailey, N. M.; Kimber, C. D.Mattern (1964) has shown that in human trypanosomiasis caused by Trypanosoma gambiense, the serum IgM immunoglobulin level is consistently raised, and this was confirmed by LUMSDEN (1965) for infection with T. rhodesiense. Although these authors showed that increased levels of serum IgM are not pathognomonic for trypanosomiasis, the observation that low levels virtually exclude the possibility of trypanosome infection is obviously relevant to the development of a screening test for diagnosis.Item The Indirect Fluorescent Antibody Technique Applied to Dried Blood, for use as a Screening Test in the Diagnosis of Human Trypanosomiasis in Africa(1967) Bailey, N.M.; Cunningham, M.P.; Kimber, C.D.; East African Trypanosomiasis Research Organization, Totoro, Uganda; East African Trypanosomiasis Research Organization, Tororo UgandaFluorescent antibody tests based on the technique developed by COONS, CREECH and JONES (1941) are widely used for the detection in serum of specific antibodies to infectious micro-organisms. FIFE and MUSCHEL (1959) described an indirect fluorescent antibody technique (1FT) for the serodiagnosis of Chagas's disease. Trypanosoma cruzi cultured on a diphasic blood agar medium was used as the antigen and, as this had to be kept moist, the entire technique was carried out in test tubes. A modification of this technique has been shown by SADUN et al. (1963) to be of value in the serodiagnosis of human trypanosomiasis. Thin blood smears from rats infected with T. CTUzi, T. gambiense and T. rhodesiense were used as antigen, and this resulted in a test which could be rapidly carried out on glass slides with serum collected from suspected cases of disease. ANDERSON et al. (1961) described a technique for the diagnosis of schistosomiasis by immunofluorescence, making use of blood samples dried on filter paper, and SADUN et al. (1963) showed that dried blood samples could be also used in the diagnosis of human trypanosomiasis. Their technique involved the elution of serum from the dried blood samples contained in plastic tubes, and the subsequent extrusion of the eluate in a carpenter's vice. This technique was somewhat tedious and time-consuming and only a limited number of tests could be carried out at anyone time. A modified technique has now been developed for the diagnosis, by immunofluorescence, of human T. rhodesiense infection. The complete procedure is carried out on glass microscope slides at room temperature, and large numbers of blood samples can be examined in a short period of time.Item A Report on Four Outbreaks Caused by Two Separate Shipments of Endrin-contaminated Flour(1967) Weeks, D.E.; ARAMCO ( Arabian American Oil Company )This report represents the compilation of information provided by many individuals from different organizations in several different countries. It was only with their fullest co-operation and understanding that this report was made possible and full acknowledgement and appreciation is extended to them. A list of these individuals and organizations is given in the Annex.Item The Epidemiology of Sleeping Sickness in Samia Location, Kenya.(1968) Wijers, D.J.B.In 1964 a T. rhodesiense sleeping sickness epidemic occurred in Alego Central Nyanza. Here the disease was transmitted by Glossina fuscipes which had left its riverine habitat and had settled in the dense hedges around the homesteads so that the flies had come into very close contact with man and his livestock. The disease was found to have a reservoir in cattle that could harbor the trypanosome for many months without showing any signs of illness. To control the epidemic and to prevent further spread, the Government decided to eradicate all tsetse in Central Nyanza by spraying the bush with insecticides. To prevent re-invasion by the fly from Uganda, all bush was cleared in a barrier zone at the western border of the sprayed area.
