| the hydro-chemical and physical conditions of the environment of the immature stages of some species of the simulium (edwardsellum) damnosum complex (diptera). | water samples were collected from breeding sites of species of the simulium (edwardsellum) damnoslm complex in upper volta, liberia and cameroon during the dry season; and in tanzania and kenya at various seasons during a period of two years. the following 20 factors were analysed at 45 breeding sites: water temperature, current velocity, ph value, conductivity free carbon dioxide, oxygen content, calcium, magnesium, potassium, sodium, alkalinity, chloride, sulphate, nitrite, nitrate, ammonium, ... | 1976 | 12601 |
| further studies on the development of onchocerca volvulus in mosquitoes. | | 1977 | 24289 |
| immunological studies on onchocerciasis. varying skin hypersensitivity and leucocyte migration inhibition in a clinical spectrum of the disease. | soluble antigen was prepared from adult worms and microfilariae of onchocerca volvulus. in 27 patients clinically characterized as having generalized type (17) and localized reaction type (10) onchocerciasis, the response to this antigen was assessed in vivo by skin testing and in vitro by leucocyte migration inhibition assay. three varieties of skin hypersensitivity were observed: immediate, arthus-type and delayed or type iv hypersensitivity. the first 2 occurred in all patients, but type iv ... | 1978 | 31781 |
| further observations on the specificity of antigen 5 of echinococcus granulosus. | the presence of ige antibodies to antigen 5 of echinococcus granulosus was detected by means of radioimmunoelectrophoresis in the sera of two of six patients infected with e. multilocularis. sera from three of these patients gave a precipitin band in gel diffusion tests identical to that produced by a monospecific rabbit anti-e. granulosus antigen 5 serum, when tested against whole hydatid fluid. sera from 19 individuals infected with fasciola hepatica, 20 with schistosoma mansoni, and 5 with wi ... | 1977 | 68114 |
| the effects of some drugs--pentamidine, stibocaptate, hoechst 33258, f 151, compound 'e' and nifurtimox--on onchocerca volvulus in chimpanzees. | several drugs were investigated for action against onchocerca volvulus in chimpanzees. pentamidine at 4 mg/kg daily for 16 days had no filaricidal action; nor did stibocaptate at 10 mg/kg monthly for 8 months. hoechst 33258, a substituted bis-benzamidazole, showed micro- and macrofilaricidal activity; f151 (an arsenical compound) showed a purely macrofilaricidal action; and compound e (a reaction product of hoechst 33258 and f151) was micro- and macrofilaricidal. the toxicity of the three last-m ... | 1977 | 74888 |
| histochemical enzyme-staining patterns of onchocerca volvulus microfilariae and their occurrence in different onchocerciasis areas. | histochemical differentiation of onchocerca volvulus microfilariae from 164 patients in west african rain-forest (liberia), sudan-savanna (upper volta), guatemala and the yemen has been carried out using a staining method for the demonstration of acid phosphatase. intrauterine microfilariae showed considerable changes in their enzyme activity during embryonic development which are probably associated with the maturation of the parasite before migration to the tissues. five distinct types of stai ... | 1978 | 84419 |
| [rate of natural infection of simulium metallicum (diptera:simuliidae) by evolved forms of onchocerca volvulus in venezuela]. | | 1977 | 139906 |
| isolation of living adult onchocerca volvulus from nodules. | a technique for the isolation of adult onchocerca volvulus from excised onchocercomata is described. the nodules are incubated in medium 199 containing 1-5 mg collagenase and 0.2 mg gentamicin per ml for 6-48 hours in a waterbath at 30-37 degrees c. a proportion of the worms can be isolated alive. | 1977 | 203061 |
| a simple technique to assess the total number of onchocerca volvulus microfilariae in skin snips. | a technique for the assessment of the total number of microfilariae in skin snips from onchocerciasis patients is described. for the digestion of the skin tissue the biopsies are incubated at room temperature for 24 hours in medium 199, containing 3 mg/ml collagenase and antibiotics. this process leaves the microfilariae unharmed. a comparative study of the emergence of the microfilariae in different media showed that only 20% of the total number were released after 30 minutes in distilled water ... | 1978 | 205977 |
| transmission potentials of onchocerca volvulus and the associated intensity of onchocerciasis in a sudan-savanna area. | | 1978 | 214908 |
| attempts to infect jirds (meriones unguiculatus) with wuchereria bancrofti, onchocerca volvulus, loa loa loa and mansonella ozzardi. | | 1977 | 267662 |
| [immunological diagnosis of filariosis in persons returning from tropical countries and in european and indigenous inhabitants of endemic areas (author's transl)]. | serum samples from persons who lived in areas where onchocerciasis occurred or who had filariasis were examined with the complement fixation test and the indirect hemagglutination test for the presence of antibodies against crude extracts from dirofilaria immitis, onchocerca volvulus, dipetalonema viteae, and ascaris suum. the results could be interpreted as follows: 1. the indirect hemagglutination test was more sensitive than the complement fixation test for the demonstration of antibodies in ... | 1977 | 271633 |
| preliminary studies on the histochemical differentiation of strains of onchocerca volvulus microfilariae in togo. | skin snips were taken from 75 people living in four villages of northern togo. the 7824 microfilariae that emerged were examined by staining for the presence of acid phosphatase. four distinct patterns of enzyme staining were observed, and descriptions of the stained microfilariae are given. the study confirms the view that a number of biological strains or variants of onchocerca volvulus coexist in west africa, and suggestions are made for further research that could result in the practical app ... | 1977 | 303958 |
| the microfilarial load in the anterior segment of the eye. a parameter of intensity of onchocerciasis. | the presence of microfilariae of onchocerca volvulus in the eye is associated with an increased risk of deterioration of existing eye lesions. an opthalmological and parasitological examination of 630 persons was carried out in a hyperendemic focus of onchocerciasis in northern togo. the prevalence of microfilariae increased in the cornea as well as the anterior chamber up to the age of 40-50 years, then decreased. the prevalence of onchocercal punctate keratitis, on the other hand, showed a pea ... | 1977 | 304397 |
| [ocular manifestations in filariasis caused by onchocerca volvulus and by loa loa]. | | 1977 | 305597 |
| ocular onchocerciasis. | well over 20 million people in the world are infected with onchocerca volvulus and it is probable that 200 000-500 000 people are blind as a result of this infection, which is the most important cause of blindness in certain areas of africa and latin america.treatment of the disease is difficult and often produces serious adverse reactions in the patient. combined use of diethylcarbamazine citrate and suramin is still the most suitable form of treatment. screening for the early detection of case ... | 1978 | 307448 |
| [suggestion for the investigation of eosinophilia caused by filaria onchocerca volvulus]. | it is proposed to search if by immunological means it is possible to distinguish eosinophilia produced by the filaria onchocerca volvulus from other eosinophiliae. the proposed methods also seem to allow the detection of the presence of the specific antibodies in other hematic cells. | 1978 | 372944 |
| the use of fixed-tissue sections to determine antibodies to onchocerca volvulus in a fluorescent antibody test. | | 1979 | 390111 |
| antigenic activity in adult dipetalonema viteae in the indirect immunofluorescent test against sera from filariasis patients--the immunofluorescent histological search for "pure" antigen. | using ifat, it has been shown that isolated egg-shells and uterine fluid of dipetalonema viteae are the most potent antigens in heterologous systems using human sera from patients infected with wuchereria bancrofti, onchocerca volvulus and loa loa, as well as in homologous systems using sera from animals infected with d. viteae. it is suggested that these antigens are unlikely to be highly species-specific, and that anatomical isolation of antigens is a necessary prerequisite to immunochemical a ... | 1979 | 394410 |
| inflammatory reactions in onchocerciasis: a report on current knowledge and recommendations for further study. | this report concerns the host's reactions to the presence of the parasite both in the course of the natural disease and during drug treatment. the various stages of onchocerca volvulus are discussed in terms of the type of tissue reaction seen. the discussion then turns to basic hypotheses concerning the etiology of these reactions, emphasis being placed on the fact that while pathological changes are considerable in some locations there is a remarkable lack of reaction in others. some of the me ... | 1979 | 396050 |
| onchocerciasis transmission potentials of four species of guatemalan simuliidae. | two complete days of collections and dissections of all black fly species landing on two persons infected with onchocerca volvulus were made at monthly intervals for 13 months within a single endemic area of guatemala. a comparison of the infective biting densities and transmission potentials showed that simulium ochraceum was the only significant vector. | 1979 | 434317 |
| electron microscopical studies on onchocerciasis. iii. the onchocerca-nodule. | six onchocerca-nodules from five liberian patients were examined by electron microscopy. the bulk of cells in the centre of the nodules consists of lymphocytes and macrophages. the lymphocytes can be observed in various stages of differentiation. a major part of the macrophages shows degenerative changes with decrease of lysosomes and increase of fatty vacuoles. near the worms epithelioid cells and giant cells can be found. other cells in the nodule include polymorphonuclear neutrophils, eosinop ... | 1979 | 442196 |
| some observations on onchocerciasis including sowda in the yemen arab republic. | a pilot study on onchocerciasis and sowda was carried out in the south-western region of the yemen arab republic. of 61 persons examined in eight villages 35 (= 57%) were found positive for microfilariae by the skin-snip method, 13 had typical manifestations of sowda, 17 had other onchocercal-suggestive skin lesions and five had subcutaneous nodules. a single larva of simulium damnosum s.i. was collected in wadi barakani. numerous larvae and pupae of s. ruficorne and s. hargreavesi were taken in ... | 1979 | 442197 |
| further studies on the relative importance of guatemalan blackfly species as vectors of onchocerca volvulus. | | 1979 | 442198 |
| onchocerciasis focus in colombia: follow-up study after 12 years. | this study is a follow-up of a 1965 investigation of the only known focus of onchocerca volvulus in colombia. in the first phase of the current study, 254 persons were examined. of the 19 individuals found to be infected with o. volvulus, the youngest was a 16-year-old male. among those included in the 1965 study, 22 were examined again for microfilariae. two were positive in both studies, 4 were positive in 1965 but negative in 1977 and the remaining 16 were negative on both occasions. the prev ... | 1979 | 453444 |
| development of onchocerca volvulus in simulium ochraceum and simulium metallicum. | the development of onchocerca volvulus was compared in simulium ochraceum and s. metallicum by maintaining infected flies under uniform conditions. larval development in s. ochraceum was synchronous and orderly so that nearly all larvae reaching the thoracic muscles from a single blood meal matured to third-stage infective larvae within 192 hours. in contrast, development in s. metallicum was asynchronous, slower, and retarded. in this species many first-larvae were malformed and stunted after t ... | 1979 | 453445 |
| vectors of onchocerca volvulus at the river toototobi, brazil. | | 1979 | 458131 |
| effect of diethylcarbamazine on the concentration of onchocerca volvulus microfilariae in hydrocoele fluid and urine. | the effect of graded doses of diethylcarbamazine on the concentration of microfilariae in the hydrocoele fluid, urine and skin of patients suffering from onchocerciasis was studied. the results showed that a significant number of microfilariae migrated into hydrocoele fluid and urine immediately after the drug was given and thereafter returned to pre-treatment levels rather more quickly in the former than the latter. the increase was found to be roughly directly proportional to the intensity of ... | 1979 | 479547 |
| the cryopreservation and in vitro cultivation of larval onchocerca volvulus. | a system developed in our laboratory for the in vitro cultivation of larval onchocerca volvulus is being employed in a series of morphogenetic, physiologic, chemotherapeutic and immunologic investigations of this parasite. because of the need for a large and readily available supply of living worms for this work, cryogenic techniques are being used for the long-term preservation of larval parasites collected in various endemic areas of guatemala, c.a. to date, microfilariae have survived frozen ... | 1979 | 507287 |
| concentration of microfilariae of onchocerca volvulus by simulium sanguineum during feeding: use in mapping parasite distribution in the skin. | | 1979 | 522121 |
| [onchocerciasis chemotherapy. ii. evaluation of two therapeutic schemes on microfilarial density, utilising the association diethylcarbamazine and levamisole (author's transl)]. | as the study of the association diethylcarbamazine-levamisole gave encouraging results on the dermal microfilarial density of onchocerca volvulus (leuckart, 1893), the authors followed it up in order to determine the optimum regimen for mass treatment. two therapeutic schemes have been tested: a--initial treatment: 14 days with the dayly dosis of respectively 200 mg of diethylcarbamazine and 120 mg of levamisole progressively reached in four days. after one year: a single dayly dosis of respecti ... | 1979 | 530049 |
| the use of an onchocerca volvulus microfilarial antigen skin test in an epidemiological survey of onchocerciasis in guatemala. | onchocerca volvulus microfilariae obtained from onchocercal nodules were used as antigenic material for a skin test. this antigen is as specific as those previously employed in skin tests, detecting 85.2% of the persons with positive diagnostic signs of onchocerciasis in endemic areas. a low rate of false positives was found in the control group in nonendemic areas. the positive rate of reactions in the persons without positive signs in the endemic areas might be due to the presences of cases no ... | 1979 | 531907 |
| failure of onchocerca volvulus to develop in culicoides. | | 1979 | 531920 |
| an evaluation of the bovine -- onchocerca gibsoni, onchocerca gutturosa model as a tertiary screen for drugs against onchocerca volvulus in man. | in this trial suramin, diethylcarbamazine, trichlorphon, levamisole, mebendazole, melarsonyl potassiu, hoechst 33258 and tinidazole were administered to cattle infected with o. gibsoni and o. gutturosa to determine the usefulness of this screen in predicting the effect of drugs in man against. o. volvulus except for melarsonyl potassium which was macrofilarticidal against o. gutturosa but not o. gibsoni when cattle were slaughtered 6 weeks after treatment. it was concluded that cattle infected w ... | 1979 | 538819 |
| the development of onchocerca volvulus in two temperate blackfly species, simulium ornatum meigen and simulium lineatum meigen. | in view of the promise shown by temperate simuliids for laboratory colonization, the ability of simulium ornatum and s. lineatum to support the development of onchocerca volvulus was investigated. an injection technique is described for the introduction of o. volvulus microfilariae from a chimpanzee into female simuliids in the absence of a bloodmeal. rpmi 1640 medium, with penicillin, streptomycin and foetal calf serum, proved satisfactory as an inoculation medium. third stage larvae were obtai ... | 1979 | 539857 |
| [sudan-savanna and rain-forest onchocerciasis in west africa: an epidemiological problem (author's transl)]. | a sudan-savanna and a rain forest onchocerciasis have been described in west africa. these two patterns of onchocerciasis have in common many epidemiological features but in hyperendemic areas there is a very essential difference between the two. in savanna the prevalence of serious ocular lesions and blindness due to onchocerciasis are much higher than in forest. therefore attempting to explain these differences five groups of factors (or working hypothesis) are reviewed: --factors related to t ... | 1979 | 554294 |
| [the epidemiological significance of neo-natal parasitism with microfilariae of onchocerca volvulus (author's transl)]. | between april 1977 and june 1978, 214 babies born of 210 mothers infected with onchocerciasis, were examined at the maternity of po hospital (upper volta). in four of them (1.9%) dermal microfilariae of onchocerca volvulus were found during the first week after birth. in two other cases microfilariae were seen in the tissue of the umbilical cord. all specimens from placentas and amniotic fluid gave negative results. the infected babies were reexamined monthly monthly from 2 to 18 months, dependi ... | 1979 | 575449 |
| the laboratory maintenance and rearing of simulium damnosum complex species as a research tool for the onchocerciasis control programme in the vola river basin. | the laboratory maintenance and rearing of stimulium damnosum complex species and the cytotaxonomic determination of reared larvae, has been useful to ocp in the following fields of investigation: 1. species identification of reinvading females. 2. distribution of biting populations of s. damnosum complex species. 3. identification of eggs and small larvae found within the ocp area. 4. host preferences of species within the complex. 5. vector potential of s. damnosum complex species for onchocerc ... | 1979 | 575451 |
| studies on the reinvasion of the onchocerciasis control programme in the volta river basin by simulium damnosum s.i. with emphasis on the south-western areas. | the aerial larvicidng operation of the onchocerciasis control programme of the world health organization which began in february 1975 resulted in a sharp reduction in simulium damnosum numbers. however, at the onset of the rainy season the fly population increased in certain areas. detailed surveys both on the ground and by helicopter did not reveal any significant failures of treatments that could account for the fly densities observed, and it was concluded that the flies must originate from so ... | 1979 | 575581 |
| ultrastructure of the microfilaria of onchocerca volvulus from mexico. | | 1977 | 592029 |
| worm burden of onchocerca volvulus in a hyperendemic village of the rain-forest in west africa. | during a study on the effects of nodulectomy on onchocerciasis in a village in the liberian rain-forest 400 onchocerca-nodules were excised from 34 inhabitants. the analysis of the nodules revealed a worm burden of 718 complete live male and 1062 complete live female worms as well as 9 male and 117 female worms which were mostly calcified and degenerating. 73% of the live females contained developing embryos or released microfilariae, the other females either contained eggs or showed empty uteri ... | 1977 | 601852 |
| effects of a single dose of metrifonate on the forest strain of onchocerca volvulus in cameroon. | | 1977 | 601853 |
| demonstration of antibodies in people infected with onchocerca volvulus using adult onchocerca gutturosa antigen. | | 1977 | 612427 |
| ultrastructural characterization of the cuticle of onchocerca volvulus microfilaria. | previous ultrastructural studies on various microfilariae have suggested the presence of a trilaminar membrane at the parasite cuticle. in the present report, the formation of the cuticle of onchocerca volvulus microfilariae was studied at different developmental stages by transmission electron microscopy of samples obtained from subcutaneous nodules of untreated patients. the cuticle is formed by the layering of surface coat fibrillar components of the hypodermal cells. no plasma membrane is fo ... | 1978 | 627951 |
| sequential affinity chromatography for the purification of antigens extracted from onchocerca volvulus adult worms. | adult onchocerca volvulus worms were extracted sequentially with buffers of various ionic strengths. the extract was incubated with purified human onchocerciasis immunoglobulin-g (igg) convalently coupled to sepharose. antigens were then eluted with 8 m urea and 7.5 m guanidine-hcl. igg contained in the eluates was removed by incubating the eluates with rabbit anti-human igg covalently coupled to sepharose. as demonstrated by double immunodiffusion and "double" crossed immunoelectrophoresis at l ... | 1978 | 644658 |
| [results of lymphography in 13 cases of onchocerciasis]. | systematic lymphographic studies in 13 cases of infection with onchocerca volvulus have enabled a "lymphographic diagram" to be made for each infected patient. the images obtained are similar to those observed in wuchereriasis. the microfilariae in onchocerciasis, however, are not transmitted in the lymphatic system, and the lesions, which vary according to the degree of infestation, show little progression. they are found mainly in the inguino-crural ganglia which are the first main ganglionic ... | 1978 | 650632 |
| onchocercal lymphadenitis: clinicopathologic study of 34 patients. | clinicopathological studies on lymph nodes of 32 africans with onchocerciasis--some complicated by hanging groin and elephantiasis of the genitalia--revealed atrophic lymphoid tissue, lymphoedema, chronic inflammation and fibrosis. we identified microfilariae of onchocerca volvulus in nodes of 24 of 32 africans (75%). there microfilariae were most numerous in the capsule and in the fibrous tissue of the medulla, but smaller numbers were also found within lymphoid tissue, in dilated lymphatics an ... | 1978 | 653785 |
| small-scale trials of six drugs against onchocerca volvulus. | six drugs in common use for the treatment of parasitic infections of man were given to 18 adult patients suffering from onchocerciasis. none of the six (metronidazole, tinidazole, mebendazole, trichlorophone, oxamniquine and pyrantel pamoate) showed any evidence of substantial activity against the microfilariae or adult worms of o. volvulus. the mean reduction in skin microfilarial counts a week after drug treatment (a measure of microfilaricidal action) was highest in patients treated with tric ... | 1978 | 675837 |
| metrifonate in onchocerciasis and lymphatic filariasis. | metrifonate, in doses of 10 mg/kg for 3 consecutive days, demonstrated partial microfilaricidal activity against onchocerca volvulus in humans. higher doses were not investigated because of the toxic reactions obtained and the absence of monitoring of the blood cholinesterase levels. spaced doses of 10 mg/kg every 2 weeks or once monthly up to 3 doses showed neither micro- nor macrofilaricidal activity against wuchereria bancrofti. | 1978 | 675839 |
| variation in delayed hypersensitivity in onchocerciasis. | soluble antigen preparations were made from onchocerca volvulus adults recovered from subcutaneous nodules, and from necator americanus third-stage larvae. intradermal skin tests were carried out on a total of 100 individuals clinically classified as having either the generalized form of onchocerciasis (86 cases, or the localized sowda form (14 cases). 91 of the people studied produced immediate reactions to the onchocercal antigen, but only those with sowda showed delayed reactions, though one ... | 1978 | 705843 |
| [the ultramicroscopic structure of microfilaria of onchocerca volvulus]. | | 1978 | 720805 |
| the indirect hemagglutination test for onchocerciasis performed with blood collected on filter paper. | in guatemala, an indirect hemagglutination (iha) test for onchocerciasis, performed with a crude saline extract of onchocerca volvulus and blood samples taken on filter paper, showed a high level of sensitivity and specificity. iha titers of blood samples from the ear lobe taken on filter paper and of sera obtained by venipuncture showed a high correlation. | 1978 | 722453 |
| epidemiology of poly-parasitism. iv. combined effects on the state of health. | the assessment of morbidity caused by chronic parasitic infections in the populations of endemic areas has remained difficult and controversial. contributing to this predicament is the frequent occurrence of multiple infections with agents that can cause a wide range of clinical manifestations, from the frequent symptomless carrier state to overt disease with more or less specific clinical manifestations. in the interpretation of the complex morbidity patterns found in rural populations of tropi ... | 1978 | 726041 |
| acid phosphatase activity in the larval stages of onchocerca volvulus developing in the vector simulium damnosum. | the staining patterns of acid phosphatase activity of the various larval stages of onchocerca volvulus from experimentally infected simulium damnosum s.l. have been described. the enzyme activity was localized in the anal vesicle/pore area of the first-stage larva, in the anal vesicle and intestine of the secong-stage larva and all over the body in the third-stage larva. early third-stage larvae could be differentiated from late third-stage infective larvae by the presence of pronounced enzyme a ... | 1978 | 726048 |
| immunologic response in onchocerciasis: relations to microfilaria density in the skin biopsy and to some frequent symptoms. | during physical and immunologic investigations on onchocerciasis in 1,298 persons in the republic of liberia, the following results were obtained. there is a significant correlation between immune response and onchocerca volvulus infection detected by a microfilaria-positive skin biopsy. on the other hand, the immune response is not influenced by the number of parasites in the skin, and there is no correlation of the immune response with onchocerca nodules and with pruritus. there is a high prop ... | 1979 | 761697 |
| preliminary identification and characterization of antigen extracts from onchocerca volvulus. | sequential extraction of onchocerca volvulus from skin nodules with buffers of different ionic strength resulted in a mixture of antigens which reacted in double immunodiffusion with sera from proven cases of onchocerciasis, the number of precipitation lines varied from 1 to 5. triton x-100 detached mainly cationic antigen proteins. it reduced the molecular size of many antigenic proteins, but did not effect their antigenicity. labelling of the extracted proteins with high specific activity 125i ... | 1976 | 824771 |
| pathology of ocular onchocerciasis: human and experimental. | involvement of the outer eye in onchocerca volvulus infection is characterized by an inflammatory process around degenerating microfilariae. individual microfilariae in the cornea may be associated with localized punctate lesions or, especially when present in large numbers, may provoke a sclerosing keratitis due to invasion by fibrovascular pannus from the limbal conjunctiva. anterior uveitis develops in some patients and can be either granulomatous, probably as a result of direct microfilarial ... | 1976 | 841643 |
| post-prandial transportation and maintenance of simulium ochraceum infected with onchocerca volvulus. | simulium ochraceum females collected after feeding on subjects harboring onchocerca volvulus were maintained and transported from guatemala to california in small plastic tubes. each tube had a perforated cap for entry of air, a wick as a reservoir for the nutrient solution (30% sucrose), a strip of filter paper for anchorage, and contained one fly. the tubes were kept in plastic boxes which, in turn, were maintained in portable coolers. direct sunlight, heat and mechanical trauma easily killed ... | 1977 | 842786 |
| lethal damage to simulium metallicum following high intakes of onchocerca volvulus microfilariae in guatemala. | high intakes of microfilariae of a guatemalan strain of onchocerca volvulus by simulium metallicum proved lethal to a considerable proportion of the flies within 24 hours of taking an infecting blood-meal. the gross histopathological changes resulting from infection were compared in groups of moribund and of apparently healthy flies during this period. the marked morbidity of the flies could be related to certain events occurring in the alimentary tract and haemocoele of the fly soon after inges ... | 1977 | 860323 |
| a simple technique for photographing living microfilariae of onchocerca volvulus in the anterior chamber of the eye. | | 1977 | 871463 |
| man-biting species of chrysops meigen, culicoides latreille and simulium latreille in ethiopia, with discussion of their vector potentialities. | human filariasis and its vectors are little known in ethiopia. wuchereia bancrofti is confined to the western lowlands and cannot be the aetiological agent of elephantiasis in the highlands. onchocerca volvulus is widespread in the south-western highlands. loa loa and dipetalonema perstans are reported here for the first time and appear to be uncommon. studies were conducted in 1973, mostly near jimma in kaffa province, on potential vectors of all but the first of these parasites. among simuliid ... | 1977 | 877992 |
| quantitative aspects of the infection of simulium ochraceum by onchocerca volvulus. | | 1977 | 888188 |
| on the development of onchocerca volvulus in mosquitoes. | in an attmept to find an experimental vector for onchocerca volvulus which can be easily be bred under laboratory conditions, the susceptibility of anopheles gambiae and aedes aegypti to infection with o. volvulus was studied. the mosquitoes were fed on a membrane feeding apparatus containing microfilariae of o. volvulus. whereas a. gambiae was refractory to infection. 14.9% of a. aegypti females became infected with developing stages, 11,2% showed young and mature third-stage larvae as well as ... | 1977 | 888189 |
| onchocerciasis: invasion of deep organs by onchocerca volvulus. | autopsies of two patients with onchocerciasis in the republic of zaïre are reported. in one patient elephantiasis who died following diethylcarbamazine therapy there were large numbers of microfilariae of onchocerca volvulus in the kidney, liver, pancreas, and lung. in the second patient, who also had leprosy and hyperinfection strongyloidiasis, we found an encapsulated adult o. volvulus in the wall of the thoracic aorta. | 1977 | 889007 |
| some observations on complement fixation in onchocerciasis in guatemalans. | recent investigations of infections with onchocerca volvulus in guatemala presented the opportunity to study some aspects of complement fixation (cf) antibody titers. an extract of adult o. volvulus obtained from nodules excised from patients was used as antigen. serum was procured from individuals whose intensity of infection was determined by skin snip counts of microfilariae. in general there was an inverse relationship between intensity of infection and cf titers. this correlation was signif ... | 1977 | 889008 |
| intracytoplasmic bacteria in onchocerca volvulus. | ultrastructural studies on onchocerca volvulus disclosed intracellular organisms within the lateral chords of adult worms and of the larval stages. in the females the organisms were also present in the oogonia, oocytes, developing eggs and microfilariae. the organisms, found within vesicles of host (filarid) membrane and limited to the cytoplasm of infected cells, appeared to have a developmental cycle consisting of three morphologically distinct forms: a small spheroidal form up to 0.3 micronm ... | 1977 | 889009 |
| a comparison of individual dissection and mass separation for recovery of onchocerca larvae from vector black flies. | the effectiveness of a mass separation technique, previously used for the extraction of larvae of lymphatic-dwelling filarial worms from batches of vector mosquitoes, was tested as a means of recovering infective-stage larvae of onchocerca volvulus from simulium ochraceum in guatemala. blood-engorged flies, collected from 10 infected human attractants, were maintained for 9 days to allow ingested microfilariae to develop to the infective stage. the numbers of onchocerca larvae recovered after gr ... | 1977 | 910287 |
| microfilariae in the cerebrospinal fluid, and neurological complications, during treatment of onchocerciasis with diethylcarbamazine. | microfilariae of onchocerca volvulus were found in the cerebrospinal fluid (csf) of 5/8 heavily infected onchocerciasis patients. during treatment with diethylcarbamazine citrate 10/11 patients showed increased numbers of 0. volvulus microfilariae in the csf. patients with concentrations of 8-31 mf/ml csf developed severe vertigo, and some other neurological manifestations, during treatment. a hypothesis is put forward to account for this clinical piciture, and its importance in relation to the ... | 1976 | 941247 |
| the populatin dynamics of onchocerca volvulus microfilariae during treatment with suramin and diethylcarbamazine. | during treatment with suramin the numbers of o. volvulus microfilariae in the blood, urine, sputum, and anterior chambers of the eye fell before those in the skin. when diethylcarbamazine (dec) was given after suramin, increased numbers of microfilariae appeared in the blood, urine, cerebrospinal fluid (csf) and sputum, but the increase in the blood was less marked, and of shorter duration, than in similar patients receiving dec without previous suramin. microfilariae are thought to enter the ur ... | 1976 | 941248 |
| subcutaneous nodules as a manifestation of onchocerciasis. a rare condition in the united states. | although infection with tissue nematodes is a significant health problem in many parts of the world, such cases are unusual in the continental united states. this report describes a case of onchocerca volvulus infection, acquired by a 38-year-old female missionary in northern brazil, that manifested as subcutaneous nodules in the groin and flank two years after the patient's return to the united states. a year previously, a wrong diagnosis of wuchereria bancrofti was made at biopsy. at that time ... | 1976 | 942304 |
| onchocercal dermatitis: ultrastructural studies of microfilariae and host tissues, before and after treatment with diethylcarbamazine (hetrazan). | specimens of skin from four cameroon patients with severe onchocercal dermatitis, before and after treatment with diethylcarbamazine (dec), were studied by light and electron microscopy. microfilariae of onchocerca volvulus have ultrastructural features resembling those of microfilariae of other genera. between the surface layer of the cuticle and the trilaminate membrane, there is an electrolucent zone which is much wider in degenerating microfilariae than in intact microfilariae. widening of t ... | 1976 | 943962 |
| antigenic diversity among onchocerca volvulus in nigeria, and immunological differences between onchocerciasis in the savanna and forest of cameroon. | onchocerciasis is a remarkably chronic infection and, in west africa, there are distinct clinical and pathological differences between the disease in the savanna and in the forest. experiments were carried out to see whether antigenic diversity among ochocerca volvulus worms might contribute to these features. extracts of adult worms and or microfilariae were analysed by disc electrophoresis on polyacrylamide gels and showed a remarkable diversity of protein patterns but no consistent savanna/fo ... | 1976 | 949872 |
| the intervals between the blood-meals of man-biting simulium damnosum (diptera: simuliidae). | six marking-recapture experiments were carried out with simulium damnosum in the cameroon republic, five in the rain-forest and one in the sudan-savanna zone. adult flies were marked by applying a small spot of oil paint to the mesonotum while they were engorging with blood on the legs of volunteers infected with onchocerca volvulus microfilariae. catches of wild flies were carried out for 12-13 days after the first day of marking, and all marked flies recaptured were examined. some of the flies ... | 1976 | 971002 |
| studies on the flight range and dispersal of simulium damnosum (diptera: simuliidae) in the rain-forest of cameroon. | five marking/recapture experiments were carried out on simulium damnosum in the rain-forest of the united republic of cameroon, in order to determine the regression in biting density at increasing distances from the marking point. flies were captured unfed, marked with fluorescent dust, and then released on the bank of a large river. recaptures were made over the six-seven days after marking, at seven stations situated from 200 m to 79 km along a large river, from the marking site. marked flies, ... | 1976 | 971003 |
| route of entry of onchocerca volvulus microfilariae into the eye. | | 1976 | 982529 |
| seasonal variation in the concentration of onchocerca volvulus microfilariae in the skin? | repeated multiple skin snips in 18 persons with onchocerciasis from the sudan-savanna of west africa suggested the possibility of a seasonal variation in microfilarial concentrations. this variation may be an evolutionary adaptation of the parasite to the climate conditions that affect the seasonal distribution of the vector, but a migration of the microfilariae in the skin layers caused by the simulium bites cannot be excluded. | 1976 | 982552 |
| [lethal coma in the course of notezine treatment and with the presence of microfilaria of onchocerca volvulus in the cerebrospinal fluid]. | | 1976 | 995616 |
| [new description of onchocerca volvulus (leuckart 1894) railliet and henry 1910, from chiapas, mexico]. | | 1976 | 1005960 |
| [infestation by onchocerca volvulus in the lusambo region (east kasai, zaire), parasitological, ophthalmological and immunologic aspects]. | | 1976 | 1015883 |
| epidemiological studies on onchocerciasis by means of a new field technique. | a new membrane filter concentration technique for the detection and quantification of onchocerca volvulus microfilariae in skin snips was compared for sensitivity and efficiency with a widely used "standard" technique. a field study was carried out in five villages in an onchocerciasis focus north-east of the town of sokodé, mô river valley, togo. use of the new technique resulted in a substantial rise in the observed prevalence and density of microfilariae. | 1976 | 1086740 |
| transmission in utero of microfilariae of onchocerca volvulus. | skin snips from newborn children and biopsy material from the umbilical cord and placenta of their mothers were examined. microfilariae of o. volvulus were found in the skin of 2 out of 11 babies and in the umbilical cords of 2 out of 11 babies born to ten mothers infected with o. volvulus in bawku hospital, ghana. | 1976 | 1088518 |
| onchocerciasis in guatemala. ii. microfilariae in urine, blood, and sputum after diethylcarbamazine. | guatermalan volunteers with onchocerciasis were given a dose of diethylcarbamazine to learn if this caused migration of microfilariae of onchocerca volvulus into urine, blood, and sputum. in 5 of the 10 volunteers, the num0ers of microfilariae in the urine increased considerably following the drug. in the same 5, relatively large numbers of microfilariae were observed in the blood and sputum specimens. response in the remaining 5 was negligible. four controls given a placebo did not respond. int ... | 1975 | 1089368 |
| onchocerciasis in guatemala. i. epidermiological studies of microfilaruria. | microfilariae of onchocerca volvulus were detected in the urine of 65 residents of three coffee plantations near yepocapa, guatemala. in this area the prevalence of microfilaruria is estimated to be between 17% and 30% of the population 10 years of age and older. almost all of the people examined had clinical manifestations of onchocerciasis and 80% of them had microfilariae in skin snips. the frequency of microfilaruria is associated with the number of microfilariae in the skin. within each age ... | 1975 | 1111355 |
| onchocerciasis in guatemala. iii. daytime periodicity of microfilariae in skin. | periodicity of microfilariae of onchocerca volvulus in the skin was not believed to exist until investigators in africa recently demonstrated diurnal periodicity. interestingly, this maximal density of microfilariae in the skin has been shown to coincide with the peak biting time of the simulium vector. the current study was performed as part of other studies in guatemala. maximal density of microfilariae in the skin was at 1000 hours or shortly therafter. this peak is earlier than reported in a ... | 1975 | 1111356 |
| onchocerciasis: prevalence of microfilaruria and other manifestations in village of cameroon. | onchoecercal microfilaruia was studied in the course of an epidemiologic investigation of diseases, infections, and general health conditions in a rural village on the adamaoua plateau in northern cameroon. microfilariae of onchocerca volvulus were observed in nearly one half of the skin snips taken from the village residents. the prevalence of onchocerciasis as diagnosed from skin snips increased with age, and was greater for males than females. the number of microfilariae per skin snip also i ... | 1975 | 1111357 |
| the geographical distribution of onchocerca volvulus infection in liberia. | the survey carried out for the assessment of onchocerciasis prevalence in liberia from 1968 to 1971 covered about 1% of the rural population. from 10.885 persons examined parasitologically, 38% were carriers of microfilariae of o. volvulus in the skin, and an additional 6.8% carried nodules but no mf. one or more onchocercal nodules were prevalent in a total of 27% of the population. geographic and sex differences were observed as well as several different patterns of increasing age. a descripti ... | 1975 | 1145727 |
| the differential dispersal of nulliparous and parous simulium damnosum. | dissections of simulium damnosum in the sudansavanna zone of cameroon indicated that nulliparous flies dispersed mainly inland away from their riverine breeding sites. parous flies also dispersed inland to the same distances as nulliparous flies, but mainly they stayed close to, or moved along, the banks of the breeding rivers. this tendency was most marked in the older parous flied. as a result of this differenital dispersal, the numbers of s. damnosum carrying infective larvae of onchocerca vo ... | 1975 | 1145728 |
| observations on filarial infections and parous rates of anthropophilic blackflies in guatemala, with reference to the transmission of onchocerca volvulus. | in guatemala, in areas of different onchocerciasis endemicity and outside the endemic zone, the main anthropophilic blackfly species simulium ochraceum, s. metallicum, s. callidum and s. gonzalezi were examined for infections with onchocerca volvulus, other filariae, and non-filarial parasites. third stage larvae, indistinguishable from those of o. volvulus were found only in 3 females of s. ochraceum out of 3,513 examined. in s. metallicum, 2 females out of 3,121 dissected harboured infective l ... | 1975 | 1162731 |
| the fate and migration of microfilariae of a guatemalan strain of onchocerca volvulus in simulium ochraceum and s. metallicum, and the role of the buccopharyngeal armature in the destruction of microfilariae. | the migration and fate of microfilariae of a guatemalan strain of onchocerca volvulus in simulium ochraceum and s. metallicum was studied. the anatomical distribution of microfilariae at various times after ingestion was recorded from a study of histological sections of the flies. s. ochraceum showed higher microfilarial intakes than s. metallicum which is probably attributed to an inherent difference in their ability to ingest. the migration of microfilariae out of the mid-gut took place essent ... | 1975 | 1162732 |
| letter: further trial of levamisole against onchocerca volvulus. | | 1975 | 1166498 |
| dipetalonema streptocerca (macfie and corson, 1922): description of the adult female. | morphologic features of the adult female dipetalonema streptocerca and microfilariae are described and illustrated from serial paraffin sections of biopsied skin from eight africans. characteristic features include a maximum diameter of 85 microns, a thin, smooth cuticle, and uteri that fill the body cavity. d. streptocerca is briefly compared to onchocerca volvulus. | 1975 | 1168032 |
| the onchocerca volvulus transmission potentials and associated patterns of onchocerciasis at four cameroon sudan-savanna villages. | the intensity of o. volvulus infection, and the prevalence of certain eye lesions and of blindness, are compared in 4 hyperendemic cameroon sudan-savanna villages. the pattern of the disease is related to the annual transmission potentials to which the communities were exposed, and the results are compared with those obtained previously in forest villages. the prevalence and intensity of o. volvulus infections in s. damnosun were more closely related to the prevalence of positive skin snip than ... | 1975 | 1172308 |
| reactions to subconjunctival inoculation of onchocerca volvulus microfilariae in pre-immunized rabbits. | rabbits, pre-immunized by intravenous inoculations of live, or of freeze-killed microfilariae of onchocerca volvulus, were later challenged by subconjunctival inoculation of live microfilariae. those pre-immunized with live microfilariae showed a marked chemotic conjunctivitis and reactions in the cornea (stromal keratitis and limbal abscesses), starting within one day of challenge. they were classed as sensitized. those pre-immunized with dead microfilariae produced minimal reactions also start ... | 1975 | 1216332 |
| factors influencing the passage of onchocerca volvulus microfilariae into the urine. | the effect of various substances on the output of onchocerca volvulus microfilariae in the urine was investigated in volunteers infected with the cameroon forest and sudan-savanna strains of the parasite. output of microfilariae in the urine tended to be higher during periods of normal activity than during sleep. during waking hours, the rate of output remained generally steady, but in some patients occasional showers of microfilariae appeared in the urine, possibly associated with the intake of ... | 1975 | 1216333 |
| effect of mebendazole and levamisole on onchocerca volvulus and dipetalonema perstans. | | 1975 | 1237183 |
| fundus lesions in the rabbit eye following inoculation of onchocerca volvulus microfilariae into the posterior segment. ii. pathology. | the injection of living microfilariae of onchocerca volvulus into the vitreous or immediately beneath the retina of rabbits gave rise to a variable degree of choroiditis. uveal inflammation was most marked in eyes inoculated directly into the retina and subretinal tissue. the choroiditis was characterised by lymphocytic, plasma cell and eosinophil infiltration and was associated in many instances with degeneration of the overlying retina and pigment epithelium. in the eyes of animals killed more ... | 1976 | 1258138 |
| fundus lesions in the rabbit eye following inoculation of onchocerca volvulus microfilariae into the posterior segment. i. the clinical picture. | live microfilariae of the cameroon forest and sudan-savanna strains of onchocerca volvulus were inoculated into the vitreous or into the subretinal layers of the eyes of rabbits. the lesions produced are described, and are compared with those seen in control animals, which had received inocula of microfilariae-free saline supernate introduced with a similar degree of operative trauma. control rabbits showed only minor pigment disturbance in the retina and choroid, near the healed operation scars ... | 1976 | 1258139 |
| clinical and laboratory changes consequent to diethylcarbamazine in patients with onchocerciasis. | this controlled study assesses the effect of a single oral dose of diethylcarbamazine (dec) in a guatemalan population with light infections of onchocerca volvulus. from 8 to 24 hours after dec, microfilariae were found with increased frequency in the urine, blood, and sputum, while the number of microfilariae per mm2 of skin decreased. the onset of signs and symptoms of reaction coincided with the appearance of microfilariae in the body fluids. motile microfilariae were noted in the anterior ch ... | 1976 | 1259086 |
| letter: route of entry of onchocerca volvulus microfilariae into the eye. | | 1976 | 1265832 |
| immunological cross-reaction between an onchocerca paramyosin-like molecule and a microfilaria surface antigen. | a monoclonal antibody (2a5b9), previously shown to be reactive with a 14 kd surface associated antigen of onchocerca microfilariae, was found to recognise a 92 kd molecule present in an adult worm extract. the antibody was used to select cdna clones with a coding capacity larger than 14 kd, from a lambda gt11 library of o. volvulus. nucleotide sequencing of the cdna of one such clone revealed extensive homology to the myosin (unc-54) and paramyosin (unc-15) genes of caenorhabditis elegans, simil ... | 1992 | 1281925 |