Evaluation sur le terrain et sur souris de la résistance des trypanosomes des bovins du plateau de l’Adamaoua au Cameroun à l’acéturate de diminazène et au chlorure d’isométamidium

Abdoulmoumini, Mamoudou; Zoli, A; Tanenbe, C.; Andrikaye, J.P.; Bourdanne,; Marcotty, Tanguy; Delespaux, V.; Clausen, Peter‐Henning; Geerts, S.

doi:10.19182/remvt.9948

Cited by 14 publications

(14 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Sera from T. congolense experimental infections with the strain MozO2J (isolated in Mozambique; L. Neves, 2012) and KONT2/133 (isolated in Cameroon; [28]) were obtained from novel trypanocide efficacy studies conducted at ClinVet (Bloemfontein, South Africa) by GALVmed (Global Alliance for Livestock Veterinary Medicine). For these studies, animals were treated with either 7 mg/kg diminazene diaceturate or 1 mg/kg isometamidium chloride and novel compounds under evaluation for efficacy against T. congolense and T. vivax .…”

Section: Methodsmentioning

confidence: 99%

Trypanosoma vivax GM6 Antigen: A Candidate Antigen for Diagnosis of African Animal Trypanosomosis in Cattle

et al. 2013

View full text Add to dashboard Cite

BackgroundDiagnosis of African animal trypanosomosis is vital to controlling this severe disease which hampers development across 10 million km2 of Africa endemic to tsetse flies. Diagnosis at the point of treatment is currently dependent on parasite detection which is unreliable, and on clinical signs, which are common to several other prevalent bovine diseases.Methodology/Principle Findingsthe repeat sequence of the GM6 antigen of Trypanosoma vivax (TvGM6), a flagellar-associated protein, was analysed from several isolates of T. vivax and found to be almost identical despite the fact that T. vivax is known to have high genetic variation. The TvGM6 repeat was recombinantly expressed in E. coli and purified. An indirect ELISA for bovine sera based on this antigen was developed. The TvGM6 indirect ELISA had a sensitivity of 91.4% (95% CI: 91.3 to 91.6) in the period following 10 days post experimental infection with T. vivax, which decreased ten-fold to 9.1% (95% CI: 7.3 to 10.9) one month post treatment. With field sera from cattle infected with T. vivax from two locations in East and West Africa, 91.5% (95% CI: 83.2 to 99.5) sensitivity and 91.3% (95% CI: 78.9 to 93.1) specificity was obtained for the TvGM6 ELISA using the whole trypanosome lysate ELISA as a reference. For heterologous T. congolense field infections, the TvGM6 ELISA had a sensitivity of 85.1% (95% CI: 76.8 to 94.4).Conclusion/Significancethis study is the first to analyse the GM6 antigen of T. vivax and the first to test the GM6 antigen on a large collection of sera from experimentally and naturally infected cattle. This study demonstrates that the TvGM6 is an excellent candidate antigen for the development of a point-of-treatment test for diagnosis of T. vivax, and to a lesser extent T. congolense, African animal trypanosomosis in cattle.

show abstract

Section: Methodsmentioning

confidence: 99%

Trypanosoma vivax GM6 Antigen: A Candidate Antigen for Diagnosis of African Animal Trypanosomosis in Cattle

et al. 2013

View full text Add to dashboard Cite

show abstract

“…Currently, there are 17 African countries ( Figure 1) in which trypanocidal drug resistance has been reported. In addition to the 13 countries mentioned by Geerts and Holmes [4], drug resistance was reported in Mozambique [12], Mali, Guinea [13] and Cameroon [14]. Moreover, in several African countries trypanocidal drug resistance is suspected to be present but has not been demonstrated using standardized tests.…”

Section: African Animal Trypanosomiasis and Drug Resistancementioning

confidence: 99%

“…Moreover, in several African countries trypanocidal drug resistance is suspected to be present but has not been demonstrated using standardized tests. Currently, there are only 10 countries (Burkina Faso, Mali, Cameroon, Ethiopia, Kenya, Nigeria, Tanzania, Zambia, Uganda and Zimbabwe) in which large-scale surveys were carried out and in which area-wide drug resistance occurred in at least one region of the country [14], [15], [16], [17] and [18]. This lack of baseline information is mainly due to the fact that the current laboratory (Box 1) and field methods (Box 2) for the detection of drug resistance are laborious, expensive and time consuming.…”

Section: African Animal Trypanosomiasis and Drug Resistancementioning

confidence: 99%

“…The presence of trypanosomes in animals with an ISM serum concentration >0.4 ng ml −1 suggests that parasites are resistant [61]. [4], [12], [13] and [14].…”

Section: Other Testsmentioning

confidence: 99%

“…If >25% of ISM-treated cattle become infected within eight weeks of exposure, drug resistance is strongly suspected. This approach can also be used for assessing whether there is suspected resistance to DA by treating the control group at the start of the experiment, and all animals that become infected during the trial, with DA and checking for the presence of parasites two weeks after treatment [14] and [63]. Furthermore, longitudinal parasitological field data can be suitably analysed using appropriate statistical techniques to detect problems of resistance to DA [64].…”

Section: Proceedings Of the 9th Symposium Of The International Societmentioning

confidence: 99%

See 2 more Smart Citations

Molecular tools for the rapid detection of drug resistance in animal trypanosomes

Delespaux

Geysen

Bossche

et al. 2008

Trends in Parasitology

104

View full text Add to dashboard Cite

There are currently 17 African countries in which animal trypanocidal drug resistance has been reported. Largescale surveys were carried out in only ten of them. The lack of baseline information is mainly due to the fact that the methods currently available for the detection of drug resistance are laborious, expensive and time consuming. In this review the mechanisms involved in resistance to isometamidium and diminazene will be discussed, together with some new molecular detection tools that have been developed recently enabling faster diagnosis of drug resistance than conventional laboratory or field tests. African animal trypanosomiasis and drug resistanceTsetse fly-transmitted trypanosomiasis is an important constraint to livestock development in sub-Saharan Africa with estimated annual losses owing to the direct and indirect effects of the disease running into billions of dollars. Approximately 9 million km 2 of sub-Saharan Africa, representing about one-third of the total land, is affected by tsetse flies [1]. Within this region, some 46-62 million head of cattle and other livestock species are at risk of the disease [2]. Trypanosomiasis is controlled either by controlling the vector or by controlling the parasite, or a combination of both. Over the years, a large arsenal of vector-control tools has been developed. Nevertheless, the control of animal trypanosomiasis in often poor rural communities has and will continue to rely heavily on the use of trypanocidal drugs. This is not surprising considering the private nature (i.e. the easy, individual, nonconcerted use) of such treatments and the difficulties in maintaining cleared areas in the absence of barriers to re-invasion of tsetse flies. Only a small group of chemoprophylactic and chemotherapeutic trypanocidal compounds are currently in use and new compounds are unlikely to become available in the near future [3]. Geerts and Holmes [4] estimated that in Africa 35 million doses of veterinary trypanocidal drugs are administered each year with isometamidium chloride (ISM), ethidium bromide (EtBr) and diminazene aceturate (DA) estimated to represent 40%, 26% and 33%, respectively, of the total trypanocidal drug market by value [5]. ISM is mainly used as a prophylactic drug and provides on average 3 months' protection (2-22 weeks) against trypanosome infection. DA has only therapeutic properties and EtBr has limited prophylactic properties and is mainly used as a therapeutic agent [6]. Considering the well known mutagenic properties of EtBr, this drug should ideally be removed from the drug market, but in practice it is still widely used in many countries. Removing this drug from the market would not jeopardize the treatment of animal trypanosomiasis because it can be replaced either by DA for curative purposes or by ISM for prophylactic purposes. When trypanosomes are resistant to ISM, EtBr will be ineffective as cross-resistance is observed between the two drugs [7]. As a result of inappropriate trypanocidal drug-use practices, there is growing co...

show abstract

Assessment of the occurrence of trypanocidal drug resistance in trypanosomes of naturally infected cattle in the Adamaoua region of Cameroon using the standard mouse test and molecular tools

et al. 2008

View full text Add to dashboard Cite

Evaluation sur le terrain et sur souris de la résistance des trypanosomes des bovins du plateau de l’Adamaoua au Cameroun à l’acéturate de diminazène et au chlorure d’isométamidium

Cited by 14 publications

References 2 publications

Trypanosoma vivax GM6 Antigen: A Candidate Antigen for Diagnosis of African Animal Trypanosomosis in Cattle

Trypanosoma vivax GM6 Antigen: A Candidate Antigen for Diagnosis of African Animal Trypanosomosis in Cattle

Molecular tools for the rapid detection of drug resistance in animal trypanosomes

Assessment of the occurrence of trypanocidal drug resistance in trypanosomes of naturally infected cattle in the Adamaoua region of Cameroon using the standard mouse test and molecular tools

Contact Info

Product

Resources

About