Soboslay PT et al. (2010) Wien Klin Wochenschr "Applied field research for comprehensive helminth infection control."

Schulz-Key H, Stingl P, Djassoa G, Karabou PK, Hamm DM, Douti JK, Heuschkel C, Agossou A, Gantin RG, Soboslay PT, Banla M

[Wien Klin Wochenschr, 2010]

The Institute for Tropical Medicine at University of Tubingen has established 30 years ago in Togo a Research Centre and Onchocerciasis Reference Laboratory (ORL). Onchocerca volvulus infection control and of other neglected tropical diseases has been the focus of activities, and those were performed together with the National Institute of Hygiene in Togo, the Medical Faculty at University of Lome, national disease control programs and district and regional hospitals. The ORL contributed significantly to the assessment of ivermectin as the prime choice for onchocerciasis treatment, and 24 years of repeated annual treatment with ivermectin has progressively reduced disease prevalence and notably the level of ocular and dermal manifestations of onchocerciasis in the endemic population. The ORL has shown that large parts of the rural population in Togo is concurrently infected with intestinal and intravascular protozoan and helminth parasites, notably school children. The application of repeated treatments with albendazole and praziquantel against Schistosoma spp. and instestinal helminthes for several years has reduced infection intensities by more than 80%. Longitudinal investigations of the cellular immune responses in adults and children have found that parasite co-infections will generate prominent pro-inflammatory responses, and a single or few interventions will not suffice to eliminate co-infections and not establish an appropriately balanced immunity.

Korbmacher F et al. (2018) Parasite Epidemiol Control "Mansonella perstans, Onchocerca volvulus and Strongyloides stercoralis infections in rural populations in central and southern Togo."

Padjoudoum K, Karabou P, Korbmacher F, Soboslay PT, Gantin RG, Poutouli WP, Kohler C, Komlan K

[Parasite Epidemiol Control, 2018]

Background: are important especially under the aspect of MDA of ivermectin which is performed since decades. Methods: =924) were collected from rural populations in the Regions Central and Plateaux in Togo, and analyzed by parasite-specific real-time PCR and ELISA techniques. Results: were 9.9%. Conclusions: may be ongoing. The degree of positive test results in the examined rural communities advocate for the continuation of MDA with ivermectin and albendazole, and further investigations should address the intensity of transmission of these parasites.

(2011) MMWR Morb Mortal Wkly Rep "Progress toward elimination of lymphatic filariasis--Togo, 2000--2009."

[MMWR Morb Mortal Wkly Rep, 2011]

Lymphatic filariasis (LF) is a disabling, mosquito-borne disease of humans caused by the parasitic filarial nematodes Wuchereria bancrofti, Brugia malayi, and Brugia timori. In 2000, the Global Program to Eliminate LF (GPELF) was established with the objective of eliminating LF as a public health problem by 2020. At that time, 80 countries had ongoing transmission, with an estimated 1.34 billion persons at risk for infection and 120 million infected. This report describes the LF elimination program in Togo, one of the 39 LF-endemic countries in the World Health Organization (WHO) African Region. Togo's approach to interrupt LF transmission included screening for infection to identify LF-endemic districts and mass drug administration (MDA) of ivermectin and albendazole in LF-endemic districts. MDA coverage and the impact of MDAs on the prevalence of infection were monitored throughout the program. In 2000, seven of 35 districts were LF-endemic, with baseline prevalence rates ranging from 1% to 22%. By 2009, MDAs had been conducted at least six times in each LF-endemic district. At that time, the decision was made to stop MDAs because reported drug coverage in LF-endemic districts exceeded 80% and no microfilaremia was detected in persons tested to monitor impact of MDAs. Togo is the first sub-Saharan country to have stopped MDAs after prevalence data suggested that LF transmission had been interrupted. Post-MDA surveillance is continuing nationally; the next step will be to certify elimination. The successful Togo program demonstrates that LF elimination can be achieved in countries with limited resources.

Komlan K et al. (2018) PLoS Negl Trop Dis "Onchocerca volvulus infection and serological prevalence, ocular onchocerciasis and parasite transmission in northern and central Togo after decades of Simulium damnosum s.l. vector control and mass drug administration of ivermectin."

Soboslay PT, Vossberg PS, Solim T, Korbmacher F, Kohler C, Gantin RG, Komlan K, Banla M, Karabou P, Padjoudoum K

[PLoS Negl Trop Dis, 2018]

BACKGROUND: Mass drug administration (MDA) of ivermectin has become the main intervention to control onchocerciasis or "river blindness". In Togo, after many years of MDA, Onchocerca volvulus infection has declined dramatically, and elimination appears achievable, but in certain river basins the current situation remains unknown. We have conducted parasitological, serological, ophthalmological, and entomological assessments in northern and central Togo within the river basins of Oti, Keran and Mo. METHODOLOGY/PRINCIPAL FINDINGS: Examinations were completed in 1,455 participants from 11 onchocerciasis sentinel villages, and O. volvulus transmission by Simulium damnosum sensu lato (s.l.) was evaluated. In children (aged 1-10 years), the prevalence of microfilariae (Mf) was 2.3% and in adults it ranged from 5.1 to 13.3%. Positive IgG4 responses to O. volvulus adult (crude) worm antigen (OvAg) and the recombinant Ov16 antigen were in all-ages 48.7% and 34.4%, and 29.1% and 14.9% in children, respectively. In the river basin villages of Keran, Mo and Oti, the IgG4 seroprevalences to OvAg in children were 51.7%, 23.5% and 12.7%, respectively, and to the Ov16 antigen 33.3% (Keran) and 5.2% (Oti). Onchocerciasis ocular lesions (punctate keratitis, evolving iridocyclitis and chorioretinitis) were observed in children and young adults. O. volvulus-specific DNA (Ov150) was detected by poolscreen in vector samples collected from Tchitchira/Keran(22.8%), Bouzalo/Mo(11.3%), Baghan/Mo(2.9%) and Pancerys/Oti(4.9%); prevalences of O. volvulus infection in S. damnosum s.l. were, respectively, 1%, 0.5%, 0.1% and 0.2%. CONCLUSIONS/SIGNIFICANCE: In the northern and central river basins in Togo, interruption of O. volvulus transmission has not yet been attained. Patent O. volvulus infections, positive antibody responses, progressive ocular onchocerciasis were diagnosed, and parasite transmission by S. damnosum s.l. occurred close to the survey locations. Future interventions may require approaches selectively targeted to non-complying endemic populations, to the seasonality of parasite transmission and national onchocerciasis control programs should harmonize cross-border MDA as a coordinated intervention.

Wu Y et al. (2003) Filaria J "Human immune responses to infective stage larval-specific chitinase of filarial parasite, Onchocerca volvulus, Ov-CHI-1."

Nutman TB, Bianco AE, McCarthy JS, Wu Y, Egerton G

[Filaria J, 2003]

BACKGROUND: Ov-CHI-1 is a chitinase specifically expressed in the infective stage larvae of the human filarial parasite Onchocerca volvulus. Evidence has show that it could be a vaccine candidate, however, there is no data available regarding the immunological status of people naturally exposed to infective stage larvae and thus provoked by this antigen. METHOD: We analysed the Ov-CHI-1-specific immune response present in four endemic foci of human onchocerciasis (Ecuador, Nigeria, Togo and Cameroon) by enzyme-linked immunosorbent assays and T-cell proliferation assays. RESULTS: In these foci of infection, antibodies to Ov-CHI-1 were found to be present in only 22% of individuals from Ecuador, but were detected in 42-62% of infected individuals in the three foci from West Africa (Nigeria, Togo and Cameroon). There was found to be no relationship between antibody level and age, gender, or infection intensity as indicated by microfilarial density and numbers of skin nodules. The isotype response to Ov-CHI-1 was dominated by the presence of IgG3, IgG1 was present to a lesser extent. Our results show a positive correlation between N- and C-termini of Ov-CHI-1 in their ability to provoke humoral and cellular immune responses in the human. Peripheral blood mononuclear cell (PBMC) proliferative responses to Ov-CHI-1 when assayed, were found to be significantly higher in the individuals from endemic areas and there was a statistically elevated response to Ov-CHI-1 in the infected individuals when compared to putative immune individuals. CONCLUSION: Ov-CHI-1 is an antigen that we have found strongly induces both humoral and cellular immune responses in humans.

Sudhaus W (1974) Zool. Jb. Syst. Bd. "Zur Systematik, Verbreitung, Okologie und Biologie neuer und wenig bekannter Rhabditiden (Nematoda) 2. Teil."

Sudhaus W

[Zool. Jb. Syst. Bd., 1974]

Five new species of the genus Rhabditis are described (Rh. riemanni n. sp., Rh. remanei n. sp., Rh. reciproca n. sp., Rh. blumi n. sp., and Rh. valida n. sp.) belonging to five subgenera (Crustorhabditis, Caenorhabditis, Rhabditis, Cephaloboides, and Pellioditis). The descriptions of four additional species are revised (Rh. ocypodis Chitwood, Rh. scanica Allgen, Rh. plicata Volk, and Rh. bengalensis Timm). The new subgenus Crustorhabditis n. subgen. derives from the paraphyletic subgenus Mesorhabditis. The species of the former group show a transition from living in littoral seaweed deposits to an obligate association with amphibious crabs (Crustacea). Information about the distribution, ecology, biology and ethology of all these species is presented (with two distribution maps, one for Rh. marina for comparison). Supplementary notes are given from Protorhabditis oxyuroides Sudhaus and Rhabditis tripartita von Linstow.

Loos M et al. (1980) Infect Immun "Analysis of the anticomplementary activity in sera of three African patients with parasitic and bacteriological infections."

Loos M, Dierich MP

[Infect Immun, 1980]

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 complement. Addition of the patients' sera to normal human serum induced a temperature-dependent consumption of C4 and C2, whereas C3 was not affected. This activity in the patients' sera eluted from a Sephadex-G-200 column with the 19 S peak and could be identified as the activated form of the first component of the complement system. The reason for the presence of activated C1, C1 in the patients' sera resides in the absence of functionally active C1 inactivator.

Klenk A et al. (1983) Z Parasitenkd "Isolation of antigen from Litomosoides carinii macrofilariae detecting serum antibodies due to Onchocerca volvulus."

Trojan HJ, Geyer E, Klenk A, Zahner H

[Z Parasitenkd, 1983]

Crude aqueous Litomosoides carinii adult worm extract was used as antigen for the detection of antibodies in sera from African patients with proven onchocerciasis (n = 45) resident in rural endemic areas of Togo and Sierra Leone. In 71% of cases this extract was found to produce 1 to 5 precipitation arcs in immunoelectrophoresis. Using a crude aqueous extract from adult Onchocerca volvulus, precipitation tests were positive in 75% of cases. The complexity of the L. carinii crude extract was shown by PAG-disc electrophoresis, PAG-electrofocusing, immunoelectrophoresis and crossed immunoelectrophoresis with the appropriate rabbit-antiserum. An antigen detecting onchocercal antibodies was isolated by two step preparative flat bed electrofocusing in granulated gel (PEGG). The antigen (pI 6.55, molecular weight 55 to 60 kd as estimated by SDS-PAG electrophoresis) was very suitable for antibody demonstration in double diffusion test and immunoelectrophoresis. Preliminary controls for specificity were performed by diffusing the antigen against sera from human and animal helminthoses including filarial infections. In contrast to the crude L. carinii extract no reaction was observed with sera from helminthic infections others than filariasis.

Houthoofd W et al. (2008) Int J Dev Biol "The embryonic cell lineage of the nematode Rhabditophanes sp."

Houthoofd W, Jacobsen K, Willems M, Coomans A, Borgonie G

[Int J Dev Biol, 2008]

One of the unique features of the model organism Caenorhabditis elegans is its invariant development, where a stereotyped cell lineage generates a fixed number of cells with a fixed cell type. It remains unclear how embryonic development evolved within the nematodes to give rise to the complex, invariant cell lineage of C. elegans. Therefore, we determined the embryonic cell lineage of the nematode, Rhabditophanes sp. (family Alloionematidae) and made detailed cell-by-cell comparison with the known cell lineages of C. elegans, Pellioditis marina and Halicephalobus gingivalis. This gave us a unique data set of four embryonic cell lineages, which allowed a detailed comparison between these cell lineages at the level of each individual cell. This lineage comparison revealed a similar complex polyclonal fate distribution in all four nematode species (85% of the cells have the same fate). It is striking that there is a conservation of a C. elegans like polyclonal cell lineage with strong left-right asymmetry. We propose that an early symmetry-breaking event in nematodes of clade IV-V is a major developmental constraint which shapes their asymmetric cell lineage.

Omar MS et al. (1981) Tropenmed Parasitol "Histochemical differentiation of filarial larvae found in Simulium damnosum s.l. in West Africa."

Omar MS, Garms R

[Tropenmed Parasitol, 1981]

The azo-dye method for the histochemical demonstration of acid phosphatase activity was used to differentiate filarial larvae within and outside th area of the Onchocerciasis Control Programme (OCP) in natural infections of female S. damnosum s.l. caught in West Africa. The histochemical patterns of 1263 larvae (all stages) dissected from 556 positive files caught at 35 catching sites during the period of reinvasion in 1978 and 1979 were determined and compared with those of O. volvulus known from experimental infections. In Mali, Ivory Coast and Upper Volta, about 16% of 3rd-stage larvae in 17.3% of invading female S. damnosum s.l. (savanna cytospecies) could be separated from those of O. volvulus-like larvae, on account of their different enzyme staining patterns. The percentage of larvae enzymatically distinguishable from O. volvulus and the flies carrying them showed a distinct geographical distribution; the highest percentages (36.4/38.4) were found in the north-west (Mali) and the lowest percentages (4.4/8.2%) were found in the interior (east-central) of the Programme area (Upper Volta). By contrast, all larvae found in S. damnosum s.l. females caught in Ghana and in Togo were morphologically as well as enzymatically similar to those of O. volvulus. Third-stage larvae of the enzymatically distinguishable "species" were found to be somewhat longer than those of O. volvulus-like larvae. Morphologically, the larvae concerned probably belong to the genus Onchocerca, but their specific identity and vertebrate host remain unknown.