| the beffa form of simulium soubrense of the s. damnosum complex in togo and benin. | the beffa form of simulium soubrense vajime & dunbar, a member of the s. sanctipauli sub-complex of the s. damnosum complex, was found breeding throughout rivers in the togo-benin gap, as far north as 9 degrees 30'n. its distribution changed with the season. in southern togo there were seasonal fluctuations in the relative abundancies of the beffa form and of s. damnosum/s.sirbanum. there was considerable temporal and regional variation in the frequencies of different colour morphs of adult flie ... | 1987 | 2979517 |
| failure of onchocerca gutturosa to develop in simulium soubrense and simulium yahense from liberia. | laboratory reared female s. soubrense and s. yahense from liberia were intrathoracically inoculated with bovine skin dwelling microfilariae of onchocerca gutturosa. of a total of 174 flies, each injected with 50 fresh microfilariae, the maximum development was to late first-stage larvae. one s. soubrense also contained two second-stage larvae and a maldeveloped third-stage larvae. no development to normal third-stage larvae was observed in any fly despite maintenance at 28 degrees c for up to 10 ... | 1987 | 3629136 |
| [microfilarial loads of onchocerca and experimental vectorial capacity of simulium soubrense-simulium sanctipauli group in the forest zone of ivory coast]. | mass treatment programs using ivermectin are now beginning in forest areas and simuli will soon be feeding on individuals with low microfilarial loads (probably < 10). most previous reports have involved higher mean loads (range: 14-6950. the purpose of this study was to ascertain the impact of low microfilarial loads on the number of infecting larvae present at the end of a parasite cycle in the simulium soubrense-simulium sanctipauli group and on availability for transmission to man by inocula ... | 1996 | 9139196 |
| onchocerca volvulus: immunohistochemical and immunoelectron microscopical distribution of a polyamine oxidizing enzyme. | we studied the distribution of a polyamine oxidizing enzyme (pao) in onchocerca volvulus and other nematode parasites by immunohistochemistry and electron microscopy with immunogold technique using a polyclonal antiserum raised against purified pao from ascaris suum. in adult o. volvulus the protein was localized in the outer zone and the area of the basal labyrinth of the hypodermis and occasionally in the outer zone of the uterine epithelium. further, the fluid in the body cavity was strongly ... | 1997 | 9217703 |
| consequences of vector behavior in epidemiology of onchocerciasis on the firestone rubber plantation in liberia. | in the current study, we have assessed the distribution of black fly vectors and the occurrence of onchocerciasis among residents of the firestone rubber plantation (frp) in liberia. the degree of endemicity of onchocerciasis on the frp is correlated with the breeding of simulium yahense on the du river and simulium soubrense on the farmington river, as well as with the feeding behavior of these black fly vectors. s. yahense is highly anthropophilic and highly susceptible to onchocerca volvulus, ... | 2006 | 16687689 |
| a case of bilateral gynandromorphism in simulioum soubrense vajime and dunbar (diptera: simuliidae). | a bilateral gynandromorph of simulium soubrense vajime and dunbar, one of the vector species of the s. damnosum theobald complex, is described as part of a continuing study of the morphology and taxonomy of the west african vectors of onchocerciasis. | 2005 | 538822 |
| onchocerciasis transmission in ghana: the human blood index of sibling species of the simulium damnosum complex. | vector-biting behaviour is important for vector-borne disease (vbd) epidemiology. the proportion of blood meals taken on humans (the human blood index, hbi), is a component of the biting rate per vector on humans in vbd transmission models. humans are the definitive host of onchocerca volvulus, but the simuliid vectors feed on a range of animals and hbi is a key indicator of the potential for human onchocerciasis transmission. ghana has a diversity of simulium damnosum complex members, which are ... | 2016 | 27494934 |
| assessment of rdna igs as a molecular marker in the simulium damnosum complex. | for five cytospecies of the simulium damnosum theobald complex of blackflies (diptera: simuliidae) from west africa, both ends of the intergenic spacer region (igs) of the rdna have been sequenced with the aim of developing specific molecular markers. no specific differences in these two regions were detected between simulium sanctipauli v. & d., simulium sirbanum v. & d., simulium soubrense v. & d., simulium squamosum enderlein and simulium yahense v. & d., except in the number of a subrepeats ... | 2002 | 12510892 |
| sibling species distributions of the simulium damnosum complex in the west african onchocerciasis control programme area during the decade 1984-93, following intensive larviciding since 1974. | during the decade from 1984 to 1993, nine species of the simulium damnosum complex of blackflies (diptera: simuliidae) were identified from the area covered by the onchocerciasis control programme. these were s. damnosum s.s., s. dieguerense, s. konkourense, s. leonense, s. sanctipauli, s. sirbanum, s. soubrense, s. squamosum, and s. yahense. some of these species were found to consist of two chromosomal variant populations. these were s. konkourense 'konkouré' and 'menankaya' forms, s. sanctipa ... | 1998 | 9824818 |
| experimental hybridization between members of the simulium damnosum complex. | males of the beffa form of simulium soubrense vajime and dunbar were successfully crossed with female s.squamosum v. & d. and s.sanctipauli v. & d. fertile eggs from both crosses were reared to larvae and, in the case of the beffa x squamosum cross, to adults. larval chromosomes from the beffa x sanctipauli cross had normally paired homologues but those of the beffa x squamosum cross showed extensive asynapsis and large heterozygous loops. the morphology of the larval and adult hybrids from the ... | 1987 | 2979532 |
| biting on human body parts of simulium vectors and its implication for the manifestation of onchocerca nodules along osun river, southwestern nigeria. | the biting preference of simulium vectors has been known to influence the distribution of onchocerca nodules and microfilariae in human body. there is, however, variation in biting pattern of simulium flies in different geographical locations. this study investigates the biting pattern on human parts by simulium vectors along osun river system where simulium soubrense beffa form has been implicated as the dominant vector and its possible implication on the distribution of onchocerca nodules on h ... | 2012 | 23135007 |
| following movements of resistant populations of simulium soubrense/sanctipauli (diptera: simuliidae) by means of chromosome inversions. | following larval insecticide treatment, resistance to the organophosphates temephos and chlorphorxim appeared in a population of the simulium soubrense/sanctipauli group of the s. damnosum complex on the bandama rivers, ivory coast. resistant populations were subsequently identified from other river basins in the north of ivory coast. a small chromosomal rearrangement, iil-a, was found to be associated with resistant populations. monitoring the presence of this inversion was used to detect the s ... | 1986 | 2431454 |
| variation and distribution of forms of simulium soubrense and s. sanctipauli in west africa. | examination of specimens from savanna areas of togo and benin attributable to simulium soubrense and s. sanctipauli according to the criteria of vajime and dunbar (1975) revealed hitherto undescribed features. cytological examination showed many larvae with the arrangement iil- 4.6/4.6.7, heterozygous for the 'diagnostic' inversion and 86% of the males possessed a previously undescribed inversion iis-6b. the occurrence of such larvae in togo and benin was associated in adult males with records o ... | 1983 | 6660970 |