| 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 |
| distribution and severity of onchocerciasis in southern benin, ghana and togo. | the onchocerciasis control programme in west africa has recently extended its operation in southern benin, ghana and togo. to estimate the number of people infected and blinded by onchocerciasis and to describe the distribution and severity of the disease in the extension area, 99 villages were selected, using a stratified random sampling procedure, and surveyed. all the ecological and entomological information available was used in the sampling procedure and in the selection of 87 non-represent ... | 1992 | 1363185 |
| 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 |
| [duality of onchocerca volvulus in man and of o. sp. cameron, 1928, in cattle. new species of bovine onchocerca in togo]. | | 1974 | 4211398 |
| [the evaluation of endemic onchocerciasis in the amou prefecture (togo)]. | we have evaluated the endemicity of the onchocerciasis in two villages of the district of amou in togo, okpahoué et onglo. we have studied 294 subjects including 136 males and 158 females representing the quarter of the population of the two villages (clinical investigation and exsanguine cutaneous biopsy): 111 persons are parasited by onchocerca volvulus that means a prevalence rate of 37.7%. we can therefore say that the villages are in a state of "meso-endemicity". we have been able to find n ... | 1994 | 8061527 |
| anthropophily, zoophily and roles in onchocerciasis transmission of the djodji form of simulium sanctipauli and s. squamosum in a forest zone of togo. | adult female simulium damnosum s.l. were caught at human and cattle bait at djodji in togo. two members of the simulium damnosum complex, the djodji form of s. sanctipauli (74.9% of the total catch) and s. squamosum (25.1%), were identified and both were mainly anthropophilic. although each species was also recorded feeding on cattle or turkey baits, most flies which were caught at animal baits did not take blood from them. flies caught unfed at the cattle bait tended to be larger and have highe ... | 1988 | 3175468 |
| 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 |
| 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 |
| deforestation and the spatio-temporal distribution of savannah and forest members of the simulium damnosum complex in southern ghana and south-western togo. | spatio-temporal data on cytotaxonomic identifications of larvae of different members of the simulium damnosum complex collected from rivers in southern ghana and south-western togo from 1975 until 1997 were analysed. when the data were combined, the percentages of savannah blackflies (s. damnosum sensu stricto and s. sirbanum) in the samples were shown to have been progressively increasing since 1975. the increases were statistically significant (p < 0.001), but the rates of increase were not li ... | 2002 | 12625139 |
| river blindness. protection for 54 cents a year. | infection by onchocerca volvulus, a parasitic worm, causes onchocerciasis (river blindness), a debilitating and often blinding disease endemic to tropical areas of africa and central and south america. the adult onchocerca volvulus invades the human host where it lives and reproduces for up to 14 years, creating millions of infant worms which cause itching, loss of skin color, rapid aging, and disfiguring skin disease in the host. onchocerciasis often causes blindness in the human host by appr ... | 1998 | 12348635 |
| prenatal immune priming in onchocerciasis-onchocerca volvulus-specific cellular responsiveness and cytokine production in newborns from infected mothers. | this study investigated the effect of maternal onchocerca volvulus infection on humoral and cellular responsiveness in newborn children and their mothers. onchocerca volvulus-specific igg isotypes and ige were significantly elevated in infected mothers and their infants. one year post partum, o. volvulus-specific igg4 was strongly reduced in children of infected mothers, while igg1 responses weakened only slightly. umbilical cord mononuclear blood cells (ucbc) and peripheral blood cells (pbmc) f ... | 1999 | 10403926 |
| antigenicity and specificity of very low molecular weight onchocerca volvulus polypeptides in the range 2.2-12.5 kd. | onchocerca volvulus polypeptides in the molecular mass range of 2.2 to 12.5 kd were separated by tricine-sds-page and the serological recognition of these very low molecular weight antigens (vlmw-ovag) was then investigated by immuno-blotting. sera from 21 onchocerciasis patients as well as from 53 individuals with other filariases were used to determine the sensitivity and specificity of detection of individual vlmw-ovag. in onchocerciasis patients, up to 16 vlmw-ovag were recognized predominan ... | 1997 | 9270732 |
| detection of loa loa-specific dna in blood from occult-infected individuals. | accurate and specific diagnosis of human loiasis is of crucial importance in an endemic area where two-thirds of infected individuals are without circulating microfilariae (occult loiasis). by using the polymerase chain reaction (pcr) and specific primers to the repeat 3 region (15r3) of the gene coding for loa loa 15-kda polyprotein antigen, dna was amplified from total blood lysate of occult-infected subjects. a 396-bp dna fragment was specifically detected. we tested the specificity of this m ... | 1997 | 9225766 |
| species-specific sequence in the repeat 3 region of the gene encoding a putative loa loa allergen: a diagnostic tool for occult loiasis. | a polymerase chain reaction (pcr)-based method to detect loa loa dna in the blood lysate of infected individuals is described. a set of primers was designed to amplify the repeat 3 sequence (15r3) of the gene encoding a putative l. loa allergen. the qualitative pcr was carried out using blood lysates from subjects from an l. loaendemic area of gabon where loiasis exists sympatrically with mansonella perstans, and from individuals from a loiasis-free area in togo infected concomitantly with m. pe ... | 1997 | 9063362 |
| analysis of the anticomplementary activity in sera of three african patients with parasitic and bacteriological infections. | the sera of three different patients from togo, africa were investigated with respect to their complement profile. the three patients were suffering from parasitic (onchocerca volvulus) and bacteriological (treponema pertenue) diseases. the total hemolytic activity (50% hemolytic complement) was markedly depressed. the analysis of the individual complement components revealed the the titers of c1, c2, c3, and c4 were lowered up to 90%, indicating an activation of the classical pathway of complem ... | 1980 | 7358423 |
| identification of two west african black flies (diptera: simuliidae) of the simulium damnosum species complex by analysis of cuticular paraffins. | simulium damnosum is known to be a sibling species complex with at least 24 cytotaxonomically distinct forms in africa. of these, six occur in the area of west africa covered by the world health organization onchocerciasis control programme. they are all vectors of onchocerca volvulus, and several are capable of migrating great distances. we report here a comparatively simple chemical method of species identification using individual adult females of pooled samples that have been collected and s ... | 1981 | 6118031 |
| morphological differences between venezuelan and african microfilariae of onchocerca volvulus. | comparative morphological and biometric characteristics of microfilariae of onchocerca gutturosa and o. volvulus from different geographical areas (upper orinoco, venezuela; togo; liberia) were assessed. "stepwise" discriminant analysis and mahalanobis estimators were applied to measure distance between populations. the results indicate a strong similarity between the two strains from the upper orinoco (venezuela) and the togo strain, as well as a clear separation between these strains and that ... | 1988 | 3235798 |