Oesophagostomiasis

14,000,000 Leading Edge Experts on the ideXlab platform

Scan Science and Technology

Contact Leading Edge Experts & Companies

Scan Science and Technology

Contact Leading Edge Experts & Companies

The Experts below are selected from a list of 93 Experts worldwide ranked by ideXlab platform

A M Polderman - One of the best experts on this subject based on the ideXlab platform.

  • Oesophugostomum Infections in Humans
    2015
    Co-Authors: A M Polderman, J Blotkamp
    Abstract:

    Oesophagostomum spp are normally found as nematode parasites of ruminants, pigs and monkeys. Occasionally hu-mans are involved. In the past decade it became clear that, in some parts of Africa, humans are adequate.final hosts. In those areas, prevalences of infection are high and morbidity is significant. The presence of lumen-dwelling adult worms, which do not seem to cause a great deal of pathology, can he demonstrated through coproculture. The presence of in-mature worms, encapsulated in nodules and responsible& pathology, on the other hand, is more difficult to confirm. It is not known what factors limit the distribution of endemic human Oesophagostomiasis to a small focus in Wesf Africa. The relationship between the ‘helminthomas ’ described a long time ago in Uganda and the human Oesophagostomum in-fections in West Africa is unclear and it remains a myster

  • the rise and fall of human Oesophagostomiasis
    Advances in Parasitology, 2010
    Co-Authors: A M Polderman, Robin B Gasser, Juventus B Ziem, Pascal Magnussen, Annette Olsen, Mark L Eberhard, S Baeta, L Van Lieshout, N Spannbrucker, J Horton
    Abstract:

    Abstract Until recently, the infections of humans with representatives of the genus Oesophagostomum were thought to be rare and of zoonotic origin. In the 1980s, it was recognised that intense transmission associated with the disease was taking place in northern Togo and Ghana. Pathology can be severe and two clinical presentations, called ‘Dapaong Tumour’ and ‘multinodular disease’, have been described. Lesions can now be efficiently and specifically visualised by ultrasound. The prevalence of infection appeared to be high in many villages, although its distribution was limited and focal. Parasitological diagnosis has been based on the demonstration of third-stage larvae in stool cultures and more recently on PCR. Molecular and epidemiological evidence supports the proposal that Oesophagostomum bifurcum infections of humans in Ghana and Togo represent a distinct genotype from that of non-human primates in the area. Mass treatment, using repeated doses of albendazole rapidly resulted in the effective elimination of human Oesophagostomiasis in the affected areas. This review takes a historic perspective on Oesophagostomiasis of humans. This chapter discusses how the unexpected success of mass treatment together with aberrant pathogenesis, the severity of pathology in humans and the limited geographic distribution of the parasite all reflect a poor adaptation of the parasite to the human host.

  • impact of repeated mass treatment on human oesophagostomum and hookworm infections in northern ghana
    Tropical Medicine & International Health, 2006
    Co-Authors: Juventus B Ziem, Pascal Magnussen, Annette Olsen, J Horton, Von L L Asigri, A M Polderman
    Abstract:

    Summary Oesophagostomum bifurcum is a common parasite of humans causing disease in parts of northern Ghana and northern Togo. The impact of repeated mass treatment with albendazole on infection with O. bifurcum and hookworm is analysed and the results compared with those in a control area where no treatment was given. At baseline, O. bifurcum and hookworm prevalences were 53.0% and 86.9%, respectively (n = 1011). After 12 months, following two rounds of albendazole treatment, prevalences decreased significantly to 5.4% for O. bifurcum and 36.8% for hookworm (n = 535). Twenty-four months after the baseline survey and following a total of four rounds of treatment, prevalences were further reduced to 0.8% and 23.4% for O. bifurcum and hookworm, respectively (n = 478). Overall, there was a significant decrease in the larval counts, measured as geometric mean larval count per 4 g of stool of O. bifurcum from 3.0 to 0.1 and of hookworm from 47.2 to 1.8. The fourth mass treatment was carried out in April 2003 by the Lymphatic Filariasis Elimination Programme. Overall, compliance to treatment varied from 70% to 80%. In the control area, Oesophagostomum prevalence increased from 18.5% to 37.0% and the intensity from 0.4 to 1.4. For hookworm, both prevalence (86.1–91.3%) and intensity (54.8–74.3) increased but not to a significant level. The prospects of eliminating human Oesophagostomiasis from the intervention area, while simultaneously achieving an important reduction of hookworm prevalences by albendazole mass treatment, are discussed. Oesophagostomum bifurcum est un parasite commun de l'homme causant des maladies dans les regions du nord du Ghana et du Togo. L'impact du traitement de masse a l'albendazole sur les infections aO. bifurcum et a l'ankylostome a ete analyse et les resultats compares a ceux des region temoin n'ayant pas recu de traitement. A la ligne de base, les prevalences de O. bifurcum et ankylostome etaient respectivement de 53,0% et 86,9% (n = 1011). Apres 12 mois et deux series de traitement a l'albendazole, les prevalences ont decru significativement, atteignant 5,4% pour O. bifurcum et 36,8% pour l'ankylostome (n = 535). Vingt quatre mois apres la ligne de base et un total de 4 series de traitement, les prevalences etaient encore plus reduites, tombant a 0,8% et 23,4% pour O. bifurcum et pour l'ankylostome respectivement (n = 478). En tout, une diminution significative du nombre de larves a ete observee, mesuree comme une moyenne geometrique de nombre de larves par 4 gr de selles, allant de 3,0 a 0,1 pour O. bifurcum et de 47,2 a 1,8 pour l'ankylostome. Le 4eme traitement en masse a ete administre en avril 2003 par le Programme d'Elimination de la Filariose Lymphatique. En general, la compliance au traitement variait de 70%a 80%. Dans la region temoin, la prevalence d’Oesophagostomum a augmente de 18,5%a 37,0% et l'intensite de 0,4 a 1,4. Pour l'ankylostome, la prevalence a augmentee (de 86,1%a 91,3%) ainsi que l'intensite (de 54,8 a 74,3) mais pas de facon significative. Les perspectives d’elimination de l’œsophagostomiase humaine dans les regions d'intervention, procurant a la fois une reduction importante de la prevalence de l'ankylostome par le traitement en masse par l'albendazole sont discutees. Oesophagostomum bifurcum es un parasito comun del hombre que causa enfermedad en lugares del norte de Ghana y norte de Togo. Se ha analizado el impacto del tratamiento masivo repetitivo con albendazol sobre la infeccion por O. bifurcum y uncinaria, comparandose los resultados con aquellos en areas control en donde no se dio tratamiento. Las prevalencias de O. bifurcum y uncinaria antes del tratamiento eran respectivamente 53.0% y 86.9% (n = 1011). Despues de 12 meses, y tras dos series de albendazol, la prevalencia decrecio significativamente al 5.4% para O. bifurcum y 36.8% para la uncinaria (n = 535). Veinticuatro meses despues de la encuesta basal y tras un total de cuatro series de tratamiento, las prevalencias se habian reducido aun mas a 0.8% y 23.4% para O. bifurcum y uncinaria respectivamente (n = 478). En general hubo una disminucion significativa en los conteos de larvas, medidos como la media geometrica de larvas por 4 g de heces, siendo para O. bifurcum de 3.0 a 0.1 y para la uncinaria de 47.2 a 1.8. El cuarto tratamiento masivo se llevo a cabo en Abril del 2003 por el Programa de Eliminacion de la Filariasis Linfatica. En general, el cumplimiento frente al tratamiento fluctuo entre 70% y 80%. En el area control, la prevalencia de Oesophagostomum aumento del 18.5% al 37.0% y la intensidad del 0.4 al 1.4. Para uncinaria, aumentaron tanto la prevalencia (86.1% a 91.3%) como la intensidad (54.8 a 74.3) pero no a un nivel significativo. Se discute la perspectiva de, mediante el tratamiento masivo con albendazol, eliminar la esofagostomiasis humana del area de intervencion, alcanzando al mismo tiempo una reduccion importante en la prevalencia uncinaria.

  • annual mass treatment with albendazole might eliminate human Oesophagostomiasis from the endemic focus in northern ghana
    Tropical Medicine & International Health, 2006
    Co-Authors: Juventus B Ziem, Pascal Magnussen, Annette Olsen, J Horton, N Spannbrucker, L Yelifari, Nana K Biritwum, A M Polderman
    Abstract:

    Summary As a follow-up to the study by Ziem et al., in this issue, efforts to control human Oesophagostomiasis and hookworm infections in northern Ghana were pursued, and the results evaluated in collaboration with the Lymphatic Filariasis Elimination Programme. This phase of evaluation of the impact of mass treatment was no longer limited to a small-scale research setting: it was done both in the context of an operationally viable national control programme and as a continuation of the Oesophagostomum Intervention Research Project (OIRP). The methods of evaluation included classical stool examination with Kato thick smears, stool culture and ultrasound examination of the colon wall. The results showed that yearly population-based albendazole–ivermectin treatment in 11 villages scattered over north-eastern Ghana, with a treatment coverage of 70–75%, resulted in a reduction of Oesophagostomum prevalence from about 20% pre-intervention to less than 1% after 2 years of mass treatment. Simultaneously, hookworm prevalence went down from 70% to approximately 15%. The data, however, cannot be readily compared with those of Ziem et al. because of the relatively crude diagnostic (single stool cultures) screening system that had to be used for the evaluation of the large-scale control programme. In the research area of the OIRP, interruption of mass treatment resulted in a rising hookworm prevalence. The Oesophagostomum prevalence, on the other hand, continued to go down. Transmission of human Oesophagostomiasis appears interruptible and small numbers of persistent cases of Oesophagostomum infection were shown insufficient to serve as a nucleus of renewed spread of the infection. The data suggest that both the infection with and the pathology due to human Oesophagostomiasis can be eliminated and that elimination is likely to be achieved through operationally feasible albendazole–ivermectin treatment as used by the Global Alliance for the Elimination of Lymphatic Filariasis. Cette etude fait suite a celle de Ziem et al. sur les efforts de controle des infections de l'oesophagostomiase et de l'ankylostome dans le nord du Ghana. Les resultats ont ete analyses en collaboration avec le Programme d'Elimination de la Filariose Lymphatique. La phase d’evaluation de l'impact du traitement de masse n'a plus ete limitee a une faible etendue d’etude mais, elle a ete realisee a la fois dans le contexte d'un programme de controle national operationnellement viable et en tant que continuation du Projet de Recherche d'Intervention sur l’Oesophagostomum. Les methodes d’evaluation comprenaient l'examen de selles par les frottis de Kato, la coproculture et l'examen ultrason de la paroi du colon. Les resultats demontrent que le traitement annuel de la population a l'albendazole–ivermectine dans 11 villages repartis dans le nord-est du Ghana, avec une couverture de 70%a 75% a resulte en une diminution de la prevalence de l’Oesophagostomum allant de 20% avant intervention a moins de 1% apres deux annees de traitement en masse. Simultanement, la prevalence de l'ankylostome est passee de 70%a environ 15%. Ces resultats ne peuvent cependant pas etre compares tels quels a ceux de Ziem et al.a cause du systeme de criblage diagnostic brut (examen d'une coproculture unique) que nous avons du appliquer pour une evaluation etendue du programme de controle. Dans la region etudiee du Projet de Recherche d'Intervention sur l’Oesophagostomum, l'interruption du traitement de masse a resulte en l'augmentation de la prevalence de l'ankylostome. La prevalence de l’Oesophagostomum a cependant continuea baisser. La transmission de l'oesophagostomiase apparait interruptible et de petits nombres de cas persistants d'infection Oesophagostomum sont insuffisants pour servir de foyers de depart a une nouvelle propagation de l'infection. Les donnees suggerent qu’a la fois l'infection et la pathologie de l'oesophagostomiase humaine peuvent etre eliminees et que cette elimination peut etre atteinte via un traitement operationnellement realisable a l'albendazole–ivermectine tel que celui utilise par l'Alliance Globale pour l'Elimination de la Filariose Lymphatique. Se han continuado los esfuerzos para controlar la esofagostomiasis humana y la infeccion por uncinaria en el norte de Ghana, como seguimiento al estudio de Ziem et al. publicado en este numero. Los resultados se han evaluado en colaboracion con el Programa de Eliminacion de la Filariasis Linfatica. Esta fase de evaluacion del impacto del tratamiento masivo no se realizo a pequena escala, limitandose al entorno de un centro de investigacion: se realizo dentro del contexto de un programa nacional de control operativamente viable y como una continuacion del Proyecto de Investigacion Interventiva Oesophagostomum [Oesophagostomum Intervention Research Project (OIRP)]. Los metodos de evaluacion incluian el clasico examen de heces mediante la tecnica de Kato, cultivo de heces y examen con ultrasonido de la pared del colon. El tratamiento anual con albendazol–ivermectina de 11 poblaciones dispersas en el noroeste de Ghana y con una cobertura del 70–75%, resulto en una reduccion de la prevalencia de Oesophagostomum de aproximadamente el 20% antes de la intervencion a menos del 1% despues de dos anos de tratamiento masivo. Simultaneamente, la prevalencia de uncinaria disminuyo del 70% a aproximadamente 15%. Sin embargo, los datos no pueden compararse con aquellos de Ziem et al. debido a que el sistema de tamizaje que se debio utilizar para la evaluacion a gran escala de un programa de control era un tanto grosero: un unico cultivo de heces. En el area de estudio de la OIRP, la interrupcion del tratamiento masivo resulto en un aumento de la prevalencia de uncinaria. Por otro lado, la prevalencia de Oesophagostomum continuo disminuyendo. Pareceria que la transmision de la esofagostomiasis humana puede interrumpirse, al demostrarse que los pequenos numeros de casos persistentes de infeccion por Oesophagostomum eran insuficientes para servir como un nucleo que reactivase la dispersion de la infeccion. Los datos sugieren que tanto la infeccion como la patologia debida a la esofagostomiasis humana pueden eliminarse y que la eliminacion puede conseguirse a traves de un tratamiento operativamente factible con albendazol–ivermectina, tal y como se utiliza en la Alianza Global para la Eliminacion de la Filariasis Linfatica.

  • insights into the epidemiology and genetic make up of oesophagostomum bifurcum from human and non human primates using molecular tools
    Parasitology, 2005
    Co-Authors: Robin B Gasser, Johanna M De Gruijter, A M Polderman
    Abstract:

    The nodule worm Oesophagostomum bifurcum (Nematoda: Strongylida) is a parasite of major human health importance predominantly in northern Togo and Ghana. Currently, it is estimated that 0·25 million people are infected with this nematode, and at least 1 million people are at risk of infection. Infection with this parasite causes significant disease as a consequence of encysted larvae in the wall of the large intestine. In spite of the health problems caused by O. bifurcum , there have been significant gaps in the knowledge of the biology, transmission and population genetics of the parasite. This review provides an account of some recent insights into the epidemiology and genetics of the parasite from human and non-human primate hosts in specific regions of Africa using molecular tools. Recent research findings are discussed mainly in relation to non-human primates being reservoirs of infection, and the consequences for the prevention and control of Oesophagostomiasis in humans are briefly discussed.

Pascal Magnussen - One of the best experts on this subject based on the ideXlab platform.

  • the rise and fall of human Oesophagostomiasis
    Advances in Parasitology, 2010
    Co-Authors: A M Polderman, Robin B Gasser, Juventus B Ziem, Pascal Magnussen, Annette Olsen, Mark L Eberhard, S Baeta, L Van Lieshout, N Spannbrucker, J Horton
    Abstract:

    Abstract Until recently, the infections of humans with representatives of the genus Oesophagostomum were thought to be rare and of zoonotic origin. In the 1980s, it was recognised that intense transmission associated with the disease was taking place in northern Togo and Ghana. Pathology can be severe and two clinical presentations, called ‘Dapaong Tumour’ and ‘multinodular disease’, have been described. Lesions can now be efficiently and specifically visualised by ultrasound. The prevalence of infection appeared to be high in many villages, although its distribution was limited and focal. Parasitological diagnosis has been based on the demonstration of third-stage larvae in stool cultures and more recently on PCR. Molecular and epidemiological evidence supports the proposal that Oesophagostomum bifurcum infections of humans in Ghana and Togo represent a distinct genotype from that of non-human primates in the area. Mass treatment, using repeated doses of albendazole rapidly resulted in the effective elimination of human Oesophagostomiasis in the affected areas. This review takes a historic perspective on Oesophagostomiasis of humans. This chapter discusses how the unexpected success of mass treatment together with aberrant pathogenesis, the severity of pathology in humans and the limited geographic distribution of the parasite all reflect a poor adaptation of the parasite to the human host.

  • impact of repeated mass treatment on human oesophagostomum and hookworm infections in northern ghana
    Tropical Medicine & International Health, 2006
    Co-Authors: Juventus B Ziem, Pascal Magnussen, Annette Olsen, J Horton, Von L L Asigri, A M Polderman
    Abstract:

    Summary Oesophagostomum bifurcum is a common parasite of humans causing disease in parts of northern Ghana and northern Togo. The impact of repeated mass treatment with albendazole on infection with O. bifurcum and hookworm is analysed and the results compared with those in a control area where no treatment was given. At baseline, O. bifurcum and hookworm prevalences were 53.0% and 86.9%, respectively (n = 1011). After 12 months, following two rounds of albendazole treatment, prevalences decreased significantly to 5.4% for O. bifurcum and 36.8% for hookworm (n = 535). Twenty-four months after the baseline survey and following a total of four rounds of treatment, prevalences were further reduced to 0.8% and 23.4% for O. bifurcum and hookworm, respectively (n = 478). Overall, there was a significant decrease in the larval counts, measured as geometric mean larval count per 4 g of stool of O. bifurcum from 3.0 to 0.1 and of hookworm from 47.2 to 1.8. The fourth mass treatment was carried out in April 2003 by the Lymphatic Filariasis Elimination Programme. Overall, compliance to treatment varied from 70% to 80%. In the control area, Oesophagostomum prevalence increased from 18.5% to 37.0% and the intensity from 0.4 to 1.4. For hookworm, both prevalence (86.1–91.3%) and intensity (54.8–74.3) increased but not to a significant level. The prospects of eliminating human Oesophagostomiasis from the intervention area, while simultaneously achieving an important reduction of hookworm prevalences by albendazole mass treatment, are discussed. Oesophagostomum bifurcum est un parasite commun de l'homme causant des maladies dans les regions du nord du Ghana et du Togo. L'impact du traitement de masse a l'albendazole sur les infections aO. bifurcum et a l'ankylostome a ete analyse et les resultats compares a ceux des region temoin n'ayant pas recu de traitement. A la ligne de base, les prevalences de O. bifurcum et ankylostome etaient respectivement de 53,0% et 86,9% (n = 1011). Apres 12 mois et deux series de traitement a l'albendazole, les prevalences ont decru significativement, atteignant 5,4% pour O. bifurcum et 36,8% pour l'ankylostome (n = 535). Vingt quatre mois apres la ligne de base et un total de 4 series de traitement, les prevalences etaient encore plus reduites, tombant a 0,8% et 23,4% pour O. bifurcum et pour l'ankylostome respectivement (n = 478). En tout, une diminution significative du nombre de larves a ete observee, mesuree comme une moyenne geometrique de nombre de larves par 4 gr de selles, allant de 3,0 a 0,1 pour O. bifurcum et de 47,2 a 1,8 pour l'ankylostome. Le 4eme traitement en masse a ete administre en avril 2003 par le Programme d'Elimination de la Filariose Lymphatique. En general, la compliance au traitement variait de 70%a 80%. Dans la region temoin, la prevalence d’Oesophagostomum a augmente de 18,5%a 37,0% et l'intensite de 0,4 a 1,4. Pour l'ankylostome, la prevalence a augmentee (de 86,1%a 91,3%) ainsi que l'intensite (de 54,8 a 74,3) mais pas de facon significative. Les perspectives d’elimination de l’œsophagostomiase humaine dans les regions d'intervention, procurant a la fois une reduction importante de la prevalence de l'ankylostome par le traitement en masse par l'albendazole sont discutees. Oesophagostomum bifurcum es un parasito comun del hombre que causa enfermedad en lugares del norte de Ghana y norte de Togo. Se ha analizado el impacto del tratamiento masivo repetitivo con albendazol sobre la infeccion por O. bifurcum y uncinaria, comparandose los resultados con aquellos en areas control en donde no se dio tratamiento. Las prevalencias de O. bifurcum y uncinaria antes del tratamiento eran respectivamente 53.0% y 86.9% (n = 1011). Despues de 12 meses, y tras dos series de albendazol, la prevalencia decrecio significativamente al 5.4% para O. bifurcum y 36.8% para la uncinaria (n = 535). Veinticuatro meses despues de la encuesta basal y tras un total de cuatro series de tratamiento, las prevalencias se habian reducido aun mas a 0.8% y 23.4% para O. bifurcum y uncinaria respectivamente (n = 478). En general hubo una disminucion significativa en los conteos de larvas, medidos como la media geometrica de larvas por 4 g de heces, siendo para O. bifurcum de 3.0 a 0.1 y para la uncinaria de 47.2 a 1.8. El cuarto tratamiento masivo se llevo a cabo en Abril del 2003 por el Programa de Eliminacion de la Filariasis Linfatica. En general, el cumplimiento frente al tratamiento fluctuo entre 70% y 80%. En el area control, la prevalencia de Oesophagostomum aumento del 18.5% al 37.0% y la intensidad del 0.4 al 1.4. Para uncinaria, aumentaron tanto la prevalencia (86.1% a 91.3%) como la intensidad (54.8 a 74.3) pero no a un nivel significativo. Se discute la perspectiva de, mediante el tratamiento masivo con albendazol, eliminar la esofagostomiasis humana del area de intervencion, alcanzando al mismo tiempo una reduccion importante en la prevalencia uncinaria.

  • annual mass treatment with albendazole might eliminate human Oesophagostomiasis from the endemic focus in northern ghana
    Tropical Medicine & International Health, 2006
    Co-Authors: Juventus B Ziem, Pascal Magnussen, Annette Olsen, J Horton, N Spannbrucker, L Yelifari, Nana K Biritwum, A M Polderman
    Abstract:

    Summary As a follow-up to the study by Ziem et al., in this issue, efforts to control human Oesophagostomiasis and hookworm infections in northern Ghana were pursued, and the results evaluated in collaboration with the Lymphatic Filariasis Elimination Programme. This phase of evaluation of the impact of mass treatment was no longer limited to a small-scale research setting: it was done both in the context of an operationally viable national control programme and as a continuation of the Oesophagostomum Intervention Research Project (OIRP). The methods of evaluation included classical stool examination with Kato thick smears, stool culture and ultrasound examination of the colon wall. The results showed that yearly population-based albendazole–ivermectin treatment in 11 villages scattered over north-eastern Ghana, with a treatment coverage of 70–75%, resulted in a reduction of Oesophagostomum prevalence from about 20% pre-intervention to less than 1% after 2 years of mass treatment. Simultaneously, hookworm prevalence went down from 70% to approximately 15%. The data, however, cannot be readily compared with those of Ziem et al. because of the relatively crude diagnostic (single stool cultures) screening system that had to be used for the evaluation of the large-scale control programme. In the research area of the OIRP, interruption of mass treatment resulted in a rising hookworm prevalence. The Oesophagostomum prevalence, on the other hand, continued to go down. Transmission of human Oesophagostomiasis appears interruptible and small numbers of persistent cases of Oesophagostomum infection were shown insufficient to serve as a nucleus of renewed spread of the infection. The data suggest that both the infection with and the pathology due to human Oesophagostomiasis can be eliminated and that elimination is likely to be achieved through operationally feasible albendazole–ivermectin treatment as used by the Global Alliance for the Elimination of Lymphatic Filariasis. Cette etude fait suite a celle de Ziem et al. sur les efforts de controle des infections de l'oesophagostomiase et de l'ankylostome dans le nord du Ghana. Les resultats ont ete analyses en collaboration avec le Programme d'Elimination de la Filariose Lymphatique. La phase d’evaluation de l'impact du traitement de masse n'a plus ete limitee a une faible etendue d’etude mais, elle a ete realisee a la fois dans le contexte d'un programme de controle national operationnellement viable et en tant que continuation du Projet de Recherche d'Intervention sur l’Oesophagostomum. Les methodes d’evaluation comprenaient l'examen de selles par les frottis de Kato, la coproculture et l'examen ultrason de la paroi du colon. Les resultats demontrent que le traitement annuel de la population a l'albendazole–ivermectine dans 11 villages repartis dans le nord-est du Ghana, avec une couverture de 70%a 75% a resulte en une diminution de la prevalence de l’Oesophagostomum allant de 20% avant intervention a moins de 1% apres deux annees de traitement en masse. Simultanement, la prevalence de l'ankylostome est passee de 70%a environ 15%. Ces resultats ne peuvent cependant pas etre compares tels quels a ceux de Ziem et al.a cause du systeme de criblage diagnostic brut (examen d'une coproculture unique) que nous avons du appliquer pour une evaluation etendue du programme de controle. Dans la region etudiee du Projet de Recherche d'Intervention sur l’Oesophagostomum, l'interruption du traitement de masse a resulte en l'augmentation de la prevalence de l'ankylostome. La prevalence de l’Oesophagostomum a cependant continuea baisser. La transmission de l'oesophagostomiase apparait interruptible et de petits nombres de cas persistants d'infection Oesophagostomum sont insuffisants pour servir de foyers de depart a une nouvelle propagation de l'infection. Les donnees suggerent qu’a la fois l'infection et la pathologie de l'oesophagostomiase humaine peuvent etre eliminees et que cette elimination peut etre atteinte via un traitement operationnellement realisable a l'albendazole–ivermectine tel que celui utilise par l'Alliance Globale pour l'Elimination de la Filariose Lymphatique. Se han continuado los esfuerzos para controlar la esofagostomiasis humana y la infeccion por uncinaria en el norte de Ghana, como seguimiento al estudio de Ziem et al. publicado en este numero. Los resultados se han evaluado en colaboracion con el Programa de Eliminacion de la Filariasis Linfatica. Esta fase de evaluacion del impacto del tratamiento masivo no se realizo a pequena escala, limitandose al entorno de un centro de investigacion: se realizo dentro del contexto de un programa nacional de control operativamente viable y como una continuacion del Proyecto de Investigacion Interventiva Oesophagostomum [Oesophagostomum Intervention Research Project (OIRP)]. Los metodos de evaluacion incluian el clasico examen de heces mediante la tecnica de Kato, cultivo de heces y examen con ultrasonido de la pared del colon. El tratamiento anual con albendazol–ivermectina de 11 poblaciones dispersas en el noroeste de Ghana y con una cobertura del 70–75%, resulto en una reduccion de la prevalencia de Oesophagostomum de aproximadamente el 20% antes de la intervencion a menos del 1% despues de dos anos de tratamiento masivo. Simultaneamente, la prevalencia de uncinaria disminuyo del 70% a aproximadamente 15%. Sin embargo, los datos no pueden compararse con aquellos de Ziem et al. debido a que el sistema de tamizaje que se debio utilizar para la evaluacion a gran escala de un programa de control era un tanto grosero: un unico cultivo de heces. En el area de estudio de la OIRP, la interrupcion del tratamiento masivo resulto en un aumento de la prevalencia de uncinaria. Por otro lado, la prevalencia de Oesophagostomum continuo disminuyendo. Pareceria que la transmision de la esofagostomiasis humana puede interrumpirse, al demostrarse que los pequenos numeros de casos persistentes de infeccion por Oesophagostomum eran insuficientes para servir como un nucleo que reactivase la dispersion de la infeccion. Los datos sugieren que tanto la infeccion como la patologia debida a la esofagostomiasis humana pueden eliminarse y que la eliminacion puede conseguirse a traves de un tratamiento operativamente factible con albendazol–ivermectina, tal y como se utiliza en la Alianza Global para la Eliminacion de la Filariasis Linfatica.

  • ultrasonographic detection and assessment of preclinical oesophagostomum bifurcum induced colonic pathology
    Clinical Infectious Diseases, 2001
    Co-Authors: P A Storey, Pascal Magnussen, N Spannbrucker, L Yelifari, G Dery, E Doehring, A M Polderman
    Abstract:

    : In northern Ghana and Togo, Oesophagostomum bifurcum infects an estimated 250,000 people, as determined by cultures of stool samples. The juvenile stages of the helminth develop within colonic wall nodules, causing Dapaong tumor or multinodular disease, at the rate of 1 case per week at Nalerigu Hospital in Ghana. Our aim was to discover whether suspected colonic-wall pathology is ultrasonographically visible in asymptomatic individuals living in the area where O. bifurcum is endemic. A total of 464 persons from 3 villages, ranging from highly infected to noninfected, were examined with ultrasonography. Anechogenic colonic lesions with posterior wall enhancement were observed in 71 (54.2%) of 131 and 57 (24.5%) of 233 persons from the villages of endemicity, and no lesions were seen in persons from the village outside the area of endemicity. We describe the lesions noted in this study as nodules caused by O. bifurcum, on the basis of their association at a population level with prevalence of larvae in stools, their expected ultrasonographic appearance and distribution (on the basis of our surgical experience with Oesophagostomiasis), and the lack of a convincing differential diagnosis.

  • the effect of albendazole on oesophagostomum bifurcum infection and pathology in children from rural northern ghana
    Annals of Tropical Medicine and Parasitology, 2001
    Co-Authors: P A Storey, Pascal Magnussen, S Bugri, A M Polderman
    Abstract:

    Ultrasonography has already revealed that up to 50% of individuals in some villages in northern Ghana have colonic pathology induced by Oesophagostomum bifurcum. Approximately 2% of those affected progress to clinical Oesophagostomiasis if left untreated. In the present study, ultrasound-positive children living in a heavily infected community were each given 5 days of treatment with albendazole (10 mg/ kg.day), early in the dry season. Treatment reduced the prevalence, number, size and half-life of the ultrasound-visible nodules, stopped the excretion of O. bifurcum eggs, and reduced the development of clinical Oesophagostomiasis during the subsequent 8 months. However, the treatment had no impact on the new infections that occurred during the following rainy season, and no impact on nodule prevalence by the end of that rainy season. Surgical management may not be essential in non-acute cases of clinical Oesophagostomiasis, as albendazole may kill the nodule-dwelling worms.

Robin B Gasser - One of the best experts on this subject based on the ideXlab platform.

  • the rise and fall of human Oesophagostomiasis
    Advances in Parasitology, 2010
    Co-Authors: A M Polderman, Robin B Gasser, Juventus B Ziem, Pascal Magnussen, Annette Olsen, Mark L Eberhard, S Baeta, L Van Lieshout, N Spannbrucker, J Horton
    Abstract:

    Abstract Until recently, the infections of humans with representatives of the genus Oesophagostomum were thought to be rare and of zoonotic origin. In the 1980s, it was recognised that intense transmission associated with the disease was taking place in northern Togo and Ghana. Pathology can be severe and two clinical presentations, called ‘Dapaong Tumour’ and ‘multinodular disease’, have been described. Lesions can now be efficiently and specifically visualised by ultrasound. The prevalence of infection appeared to be high in many villages, although its distribution was limited and focal. Parasitological diagnosis has been based on the demonstration of third-stage larvae in stool cultures and more recently on PCR. Molecular and epidemiological evidence supports the proposal that Oesophagostomum bifurcum infections of humans in Ghana and Togo represent a distinct genotype from that of non-human primates in the area. Mass treatment, using repeated doses of albendazole rapidly resulted in the effective elimination of human Oesophagostomiasis in the affected areas. This review takes a historic perspective on Oesophagostomiasis of humans. This chapter discusses how the unexpected success of mass treatment together with aberrant pathogenesis, the severity of pathology in humans and the limited geographic distribution of the parasite all reflect a poor adaptation of the parasite to the human host.

  • insights into the epidemiology and genetic make up of oesophagostomum bifurcum from human and non human primates using molecular tools
    Parasitology, 2005
    Co-Authors: Robin B Gasser, Johanna M De Gruijter, A M Polderman
    Abstract:

    The nodule worm Oesophagostomum bifurcum (Nematoda: Strongylida) is a parasite of major human health importance predominantly in northern Togo and Ghana. Currently, it is estimated that 0·25 million people are infected with this nematode, and at least 1 million people are at risk of infection. Infection with this parasite causes significant disease as a consequence of encysted larvae in the wall of the large intestine. In spite of the health problems caused by O. bifurcum , there have been significant gaps in the knowledge of the biology, transmission and population genetics of the parasite. This review provides an account of some recent insights into the epidemiology and genetics of the parasite from human and non-human primate hosts in specific regions of Africa using molecular tools. Recent research findings are discussed mainly in relation to non-human primates being reservoirs of infection, and the consequences for the prevention and control of Oesophagostomiasis in humans are briefly discussed.

  • oesophagostomum bifurcum in non human primates is not a potential reservoir for human infection in ghana
    Tropical Medicine & International Health, 2005
    Co-Authors: Lisette Van Lieshout, Johanna M De Gruijter, Michael Adunsiah, Michael Haizel, Jaco J Verweij, Eric A T Brienen, Robin B Gasser, A M Polderman
    Abstract:

    Summary In northern Togo and Ghana, human infection with the parasitic nematode Oesophagostomum bifurcum is of major health importance. Elsewhere, Oesophagostomiasis is considered a zoonotic infection, non-human primates being the natural host. We examined 349 faecal samples of the olive baboon, mona monkey and black and white colobus monkey from two geographically distinct areas in Ghana, outside the region endemic for O. bifurcum in humans. Using both microscopy and species-specific PCR, we found a high prevalence of O. bifurcum (75–99%) in olive baboons and mona monkeys. The majority of the test-positive faecal samples contained large numbers of larvae after copro-culture (>100). No O. bifurcum was detected in the faeces of the black and white colobus monkeys. Observational studies on the behaviour of the non-human primates, focusing on defecation, food consumption and the sharing of habitat with the local human population, indicated favourable conditions for zoonotic transmission. Given that no human infection with O. bifurcum has been reported from either study area, the present findings support the hypothesis that O. bifurcum from humans in the north of Ghana, and O. bifurcum from olive baboons and/or mona monkeys are distinct.

  • pcr assay for the specific amplification of oesophagostomum bifurcum dna from human faeces
    International Journal for Parasitology, 2000
    Co-Authors: Jaco J Verweij, A M Polderman, Maarten C Wimmenhove, Robin B Gasser
    Abstract:

    Oesophagostomiasis in humans due to infection with Oesophagostomum bifurcum (nodule worm) is of major human health significance in northern Togo and Ghana where the human hookworm, Necator americanus, also exists at high prevalence. Accurate diagnosis of O. bifurcum infection in humans is central to studying the epidemiology and controlling the parasite. To overcome limitations of current copro-diagnostic methods, we have developed an alternative, molecular approach. Utilising genetic markers in the second internal transcribed spacer (ITS-2) of ribosomal DNA, we have established a two-step, semi-nested PCR method for the specific amplification of minute amounts (fg) of O. bifurcum DNA from human faecal samples. Using a panel of 155 well-defined faecal and DNA samples, the assay achieved a sensitivity of 94.6% and a specificity of 100%. This PCR assay will be useful for the diagnosis of O. bifurcum infection and as a molecular tool for elucidating the epidemiology of human Oesophagostomiasis.

  • characterization of oesophagostomum bifurcum and necator americanus by pcr rflp of rdna
    Journal of Parasitology, 1997
    Co-Authors: A Romstad, J R Monti, A M Polderman, Peter Nansen, Robin B Gasser, Neil B Chilton
    Abstract:

    Esophagostomiasis in humans due to infection with Oesophagostomum bifurcum (nodular worm) is of major human health significance in northern Togo and Ghana, where Necator americanus (human hookworm) also exists at high prevalence. Yet, very little is known about the transmission patterns of O. bifurcum, which is in part due to the difficulties in diagnosis and in differentiating some life-cycle stages of O. bifurcum from N. americanus using morphological features. As a first step toward developing a molecular-diagnostic assay, it was evaluated whether ribosomal (r)DNA could provide genetic markers for the identification of O. bifurcum and N. americanus to species. Internal transcribed spacer rDNA (plus flanking and intervening sequences) was analyzed by polymerase chain reaction-linked restriction fragment length polymorphism (PCR-RFLP) using several restriction endonucleases. The analysis showed that there was no detectable intraspecific difference in the size of the PCR products among multiple samples, that there was a consistent size difference in the products (of 110 bp or 350 bp, depending on region amplified) between the species, and that there was no significant variation in restriction patterns within each species. These results indicate that the rDNA spanning the internal transcribed spacers provides useful genetic markers for the identification of O. bifurcum and N. americanus to species, which has important implications for developing PCR-based tools to study the epidemiology and population biology of O. bifurcum.

P A Storey - One of the best experts on this subject based on the ideXlab platform.

  • ultrasonographic detection and assessment of preclinical oesophagostomum bifurcum induced colonic pathology
    Clinical Infectious Diseases, 2001
    Co-Authors: P A Storey, Pascal Magnussen, N Spannbrucker, L Yelifari, G Dery, E Doehring, A M Polderman
    Abstract:

    : In northern Ghana and Togo, Oesophagostomum bifurcum infects an estimated 250,000 people, as determined by cultures of stool samples. The juvenile stages of the helminth develop within colonic wall nodules, causing Dapaong tumor or multinodular disease, at the rate of 1 case per week at Nalerigu Hospital in Ghana. Our aim was to discover whether suspected colonic-wall pathology is ultrasonographically visible in asymptomatic individuals living in the area where O. bifurcum is endemic. A total of 464 persons from 3 villages, ranging from highly infected to noninfected, were examined with ultrasonography. Anechogenic colonic lesions with posterior wall enhancement were observed in 71 (54.2%) of 131 and 57 (24.5%) of 233 persons from the villages of endemicity, and no lesions were seen in persons from the village outside the area of endemicity. We describe the lesions noted in this study as nodules caused by O. bifurcum, on the basis of their association at a population level with prevalence of larvae in stools, their expected ultrasonographic appearance and distribution (on the basis of our surgical experience with Oesophagostomiasis), and the lack of a convincing differential diagnosis.

  • human Oesophagostomiasis a histomorphometric study of 13 new cases in northern ghana
    Virchows Archiv, 2001
    Co-Authors: J J Bogers, A M Polderman, P A Storey, G Faile, E Hewitt, L Yelifari, E Van Marck
    Abstract:

    Oesophagostomiasis is an infrequently described and recognised parasitic infection in humans, caused by Oesophagostomum bifurcum. Although the disease is most often found in the northern part of Togo and the neighbouring part of Ghana, sporadic cases have been described in other parts of Africa and in Asia and South America: Uganda, Ivory Coast, Sudan, Kenya, Ethiopia, Indonesia, Malaysia and Brazil. Infection probably occurs by way of the ingestion of L3 larvae. These larvae penetrate the intestinal wall, especially that of the colon. Some of these larvae develop into young adult worms and return to the bowel lumen. Other larvae, however, develop into immature worms, which fail to settle in the lumen, forming abscesses in the bowel wall and causing pathology. In the literature 105 human cases have been described, many originating in the northern regions of Ghana and Togo. The present study was performed to evaluate 13 new cases originating in the northern part of Ghana (7 female and 6 male patients, aged between 2 and 60 years). Histopathologically, the patients could be divided into two groups: the first group showed multinodular disease, while patients in the second group presented with a single, nodular mass. In the first group, abscesses were seen throughout the colonic wall. The mean size of the cavities was 4.3±0.7 mm. There was no relation between the size and the localisation in the colonic wall. Abscesses were significantly larger in male patients than in female patients. There was no correlation with age. In the second group, histopathological examination showed a cyst of variable wall thickness with very limited inflammation. These cysts represented older lesions, often encapsulated in the mesentery. In conclusion, in this study we present 13 new cases of human Oesophagostomiasis. The abscess formation was found to be organ specific, independent of age, and gender-related, producing a more intense tissue reaction in male patients.

  • the effect of albendazole on oesophagostomum bifurcum infection and pathology in children from rural northern ghana
    Annals of Tropical Medicine and Parasitology, 2001
    Co-Authors: P A Storey, Pascal Magnussen, S Bugri, A M Polderman
    Abstract:

    Ultrasonography has already revealed that up to 50% of individuals in some villages in northern Ghana have colonic pathology induced by Oesophagostomum bifurcum. Approximately 2% of those affected progress to clinical Oesophagostomiasis if left untreated. In the present study, ultrasound-positive children living in a heavily infected community were each given 5 days of treatment with albendazole (10 mg/ kg.day), early in the dry season. Treatment reduced the prevalence, number, size and half-life of the ultrasound-visible nodules, stopped the excretion of O. bifurcum eggs, and reduced the development of clinical Oesophagostomiasis during the subsequent 8 months. However, the treatment had no impact on the new infections that occurred during the following rainy season, and no impact on nodule prevalence by the end of that rainy season. Surgical management may not be essential in non-acute cases of clinical Oesophagostomiasis, as albendazole may kill the nodule-dwelling worms.

  • ultrasound diagnosis of Oesophagostomiasis
    British Journal of Radiology, 2000
    Co-Authors: P A Storey, A M Polderman, Sylvester D Anemana, J A Van Oostayen, Pascal Magnussen
    Abstract:

    Human infection with Oesophagostomum bifurcum, a parasitic intestinal helminth, is endemic in parts of West Africa. Oesophagostomum bifurcum juveniles develop in the colonic wall, causing pus-filled granulomas. The pathology has two distinct forms. Multinodular Oesophagostomiasis comprises hundreds of small nodules within a thickened, oedematous wall of the large intestine. Uninodular Oesophagostomiasis, called the Dapaong tumour, presents as a painful 30-60 mm granulomatous mass in the abdominal wall or within the abdominal cavity. Diagnosis of Oesophagostomiasis on clinical grounds alone is difficult. We describe cases illustrating the ultrasound appearance of these two presentations. Multinodular disease shows nodular "target" and "pseudokidney" colonic lesions. The Dapaong tumour is an echo-free ovoid lumen enveloped within a well defined poorly reflective wall.

  • clinical epidemiology and classification of human Oesophagostomiasis
    Transactions of The Royal Society of Tropical Medicine and Hygiene, 2000
    Co-Authors: P A Storey, A M Polderman, G Faile, E Hewitt, L Yelifari, Pascal Magnussen
    Abstract:

    The intestinal helminth Oesophagostomum bifurcum is highly and focally endemic in northern Ghana and Togo, and its juveniles produce a nodular inflammatory response as they develop in the intestinal wall. This pathology can produce clinical symptoms. We report on 156 cases of Oesophagostomiasis presenting in 1996-98 to Nalerigu hospital in northern Ghana. The disease accounted for 0.2% of the out-patient department new presentations (about 1 patient per week), and 1% (16) of the major acute surgical cases. Children aged 5-9 years were most commonly affected. Multinodular disease (13% of the cases) results from hundreds of pea-sized nodules within the colon wall and other intra-abdominal structures, and presents with general abdominal pain, persistent diarrhoea and weight loss. Dapaong tumour (87%) presents as an abdominal inflammatory mass often associated with fever. The 3-6-cm tumour is painful, well-delineated, smooth, spherical, 'wooden', periumbilical, and adhered to the abdominal wall. Cases most commonly presented during the late rains and early dry season. Diagnosis by ultrasound has reduced the need for exploratory surgery, and the ability to sonographically evaluate conservative treatment with albendazole has curtailed management by colectomy or incision and drainage.

Juventus B Ziem - One of the best experts on this subject based on the ideXlab platform.

  • the rise and fall of human Oesophagostomiasis
    Advances in Parasitology, 2010
    Co-Authors: A M Polderman, Robin B Gasser, Juventus B Ziem, Pascal Magnussen, Annette Olsen, Mark L Eberhard, S Baeta, L Van Lieshout, N Spannbrucker, J Horton
    Abstract:

    Abstract Until recently, the infections of humans with representatives of the genus Oesophagostomum were thought to be rare and of zoonotic origin. In the 1980s, it was recognised that intense transmission associated with the disease was taking place in northern Togo and Ghana. Pathology can be severe and two clinical presentations, called ‘Dapaong Tumour’ and ‘multinodular disease’, have been described. Lesions can now be efficiently and specifically visualised by ultrasound. The prevalence of infection appeared to be high in many villages, although its distribution was limited and focal. Parasitological diagnosis has been based on the demonstration of third-stage larvae in stool cultures and more recently on PCR. Molecular and epidemiological evidence supports the proposal that Oesophagostomum bifurcum infections of humans in Ghana and Togo represent a distinct genotype from that of non-human primates in the area. Mass treatment, using repeated doses of albendazole rapidly resulted in the effective elimination of human Oesophagostomiasis in the affected areas. This review takes a historic perspective on Oesophagostomiasis of humans. This chapter discusses how the unexpected success of mass treatment together with aberrant pathogenesis, the severity of pathology in humans and the limited geographic distribution of the parasite all reflect a poor adaptation of the parasite to the human host.

  • impact of repeated mass treatment on human oesophagostomum and hookworm infections in northern ghana
    Tropical Medicine & International Health, 2006
    Co-Authors: Juventus B Ziem, Pascal Magnussen, Annette Olsen, J Horton, Von L L Asigri, A M Polderman
    Abstract:

    Summary Oesophagostomum bifurcum is a common parasite of humans causing disease in parts of northern Ghana and northern Togo. The impact of repeated mass treatment with albendazole on infection with O. bifurcum and hookworm is analysed and the results compared with those in a control area where no treatment was given. At baseline, O. bifurcum and hookworm prevalences were 53.0% and 86.9%, respectively (n = 1011). After 12 months, following two rounds of albendazole treatment, prevalences decreased significantly to 5.4% for O. bifurcum and 36.8% for hookworm (n = 535). Twenty-four months after the baseline survey and following a total of four rounds of treatment, prevalences were further reduced to 0.8% and 23.4% for O. bifurcum and hookworm, respectively (n = 478). Overall, there was a significant decrease in the larval counts, measured as geometric mean larval count per 4 g of stool of O. bifurcum from 3.0 to 0.1 and of hookworm from 47.2 to 1.8. The fourth mass treatment was carried out in April 2003 by the Lymphatic Filariasis Elimination Programme. Overall, compliance to treatment varied from 70% to 80%. In the control area, Oesophagostomum prevalence increased from 18.5% to 37.0% and the intensity from 0.4 to 1.4. For hookworm, both prevalence (86.1–91.3%) and intensity (54.8–74.3) increased but not to a significant level. The prospects of eliminating human Oesophagostomiasis from the intervention area, while simultaneously achieving an important reduction of hookworm prevalences by albendazole mass treatment, are discussed. Oesophagostomum bifurcum est un parasite commun de l'homme causant des maladies dans les regions du nord du Ghana et du Togo. L'impact du traitement de masse a l'albendazole sur les infections aO. bifurcum et a l'ankylostome a ete analyse et les resultats compares a ceux des region temoin n'ayant pas recu de traitement. A la ligne de base, les prevalences de O. bifurcum et ankylostome etaient respectivement de 53,0% et 86,9% (n = 1011). Apres 12 mois et deux series de traitement a l'albendazole, les prevalences ont decru significativement, atteignant 5,4% pour O. bifurcum et 36,8% pour l'ankylostome (n = 535). Vingt quatre mois apres la ligne de base et un total de 4 series de traitement, les prevalences etaient encore plus reduites, tombant a 0,8% et 23,4% pour O. bifurcum et pour l'ankylostome respectivement (n = 478). En tout, une diminution significative du nombre de larves a ete observee, mesuree comme une moyenne geometrique de nombre de larves par 4 gr de selles, allant de 3,0 a 0,1 pour O. bifurcum et de 47,2 a 1,8 pour l'ankylostome. Le 4eme traitement en masse a ete administre en avril 2003 par le Programme d'Elimination de la Filariose Lymphatique. En general, la compliance au traitement variait de 70%a 80%. Dans la region temoin, la prevalence d’Oesophagostomum a augmente de 18,5%a 37,0% et l'intensite de 0,4 a 1,4. Pour l'ankylostome, la prevalence a augmentee (de 86,1%a 91,3%) ainsi que l'intensite (de 54,8 a 74,3) mais pas de facon significative. Les perspectives d’elimination de l’œsophagostomiase humaine dans les regions d'intervention, procurant a la fois une reduction importante de la prevalence de l'ankylostome par le traitement en masse par l'albendazole sont discutees. Oesophagostomum bifurcum es un parasito comun del hombre que causa enfermedad en lugares del norte de Ghana y norte de Togo. Se ha analizado el impacto del tratamiento masivo repetitivo con albendazol sobre la infeccion por O. bifurcum y uncinaria, comparandose los resultados con aquellos en areas control en donde no se dio tratamiento. Las prevalencias de O. bifurcum y uncinaria antes del tratamiento eran respectivamente 53.0% y 86.9% (n = 1011). Despues de 12 meses, y tras dos series de albendazol, la prevalencia decrecio significativamente al 5.4% para O. bifurcum y 36.8% para la uncinaria (n = 535). Veinticuatro meses despues de la encuesta basal y tras un total de cuatro series de tratamiento, las prevalencias se habian reducido aun mas a 0.8% y 23.4% para O. bifurcum y uncinaria respectivamente (n = 478). En general hubo una disminucion significativa en los conteos de larvas, medidos como la media geometrica de larvas por 4 g de heces, siendo para O. bifurcum de 3.0 a 0.1 y para la uncinaria de 47.2 a 1.8. El cuarto tratamiento masivo se llevo a cabo en Abril del 2003 por el Programa de Eliminacion de la Filariasis Linfatica. En general, el cumplimiento frente al tratamiento fluctuo entre 70% y 80%. En el area control, la prevalencia de Oesophagostomum aumento del 18.5% al 37.0% y la intensidad del 0.4 al 1.4. Para uncinaria, aumentaron tanto la prevalencia (86.1% a 91.3%) como la intensidad (54.8 a 74.3) pero no a un nivel significativo. Se discute la perspectiva de, mediante el tratamiento masivo con albendazol, eliminar la esofagostomiasis humana del area de intervencion, alcanzando al mismo tiempo una reduccion importante en la prevalencia uncinaria.

  • annual mass treatment with albendazole might eliminate human Oesophagostomiasis from the endemic focus in northern ghana
    Tropical Medicine & International Health, 2006
    Co-Authors: Juventus B Ziem, Pascal Magnussen, Annette Olsen, J Horton, N Spannbrucker, L Yelifari, Nana K Biritwum, A M Polderman
    Abstract:

    Summary As a follow-up to the study by Ziem et al., in this issue, efforts to control human Oesophagostomiasis and hookworm infections in northern Ghana were pursued, and the results evaluated in collaboration with the Lymphatic Filariasis Elimination Programme. This phase of evaluation of the impact of mass treatment was no longer limited to a small-scale research setting: it was done both in the context of an operationally viable national control programme and as a continuation of the Oesophagostomum Intervention Research Project (OIRP). The methods of evaluation included classical stool examination with Kato thick smears, stool culture and ultrasound examination of the colon wall. The results showed that yearly population-based albendazole–ivermectin treatment in 11 villages scattered over north-eastern Ghana, with a treatment coverage of 70–75%, resulted in a reduction of Oesophagostomum prevalence from about 20% pre-intervention to less than 1% after 2 years of mass treatment. Simultaneously, hookworm prevalence went down from 70% to approximately 15%. The data, however, cannot be readily compared with those of Ziem et al. because of the relatively crude diagnostic (single stool cultures) screening system that had to be used for the evaluation of the large-scale control programme. In the research area of the OIRP, interruption of mass treatment resulted in a rising hookworm prevalence. The Oesophagostomum prevalence, on the other hand, continued to go down. Transmission of human Oesophagostomiasis appears interruptible and small numbers of persistent cases of Oesophagostomum infection were shown insufficient to serve as a nucleus of renewed spread of the infection. The data suggest that both the infection with and the pathology due to human Oesophagostomiasis can be eliminated and that elimination is likely to be achieved through operationally feasible albendazole–ivermectin treatment as used by the Global Alliance for the Elimination of Lymphatic Filariasis. Cette etude fait suite a celle de Ziem et al. sur les efforts de controle des infections de l'oesophagostomiase et de l'ankylostome dans le nord du Ghana. Les resultats ont ete analyses en collaboration avec le Programme d'Elimination de la Filariose Lymphatique. La phase d’evaluation de l'impact du traitement de masse n'a plus ete limitee a une faible etendue d’etude mais, elle a ete realisee a la fois dans le contexte d'un programme de controle national operationnellement viable et en tant que continuation du Projet de Recherche d'Intervention sur l’Oesophagostomum. Les methodes d’evaluation comprenaient l'examen de selles par les frottis de Kato, la coproculture et l'examen ultrason de la paroi du colon. Les resultats demontrent que le traitement annuel de la population a l'albendazole–ivermectine dans 11 villages repartis dans le nord-est du Ghana, avec une couverture de 70%a 75% a resulte en une diminution de la prevalence de l’Oesophagostomum allant de 20% avant intervention a moins de 1% apres deux annees de traitement en masse. Simultanement, la prevalence de l'ankylostome est passee de 70%a environ 15%. Ces resultats ne peuvent cependant pas etre compares tels quels a ceux de Ziem et al.a cause du systeme de criblage diagnostic brut (examen d'une coproculture unique) que nous avons du appliquer pour une evaluation etendue du programme de controle. Dans la region etudiee du Projet de Recherche d'Intervention sur l’Oesophagostomum, l'interruption du traitement de masse a resulte en l'augmentation de la prevalence de l'ankylostome. La prevalence de l’Oesophagostomum a cependant continuea baisser. La transmission de l'oesophagostomiase apparait interruptible et de petits nombres de cas persistants d'infection Oesophagostomum sont insuffisants pour servir de foyers de depart a une nouvelle propagation de l'infection. Les donnees suggerent qu’a la fois l'infection et la pathologie de l'oesophagostomiase humaine peuvent etre eliminees et que cette elimination peut etre atteinte via un traitement operationnellement realisable a l'albendazole–ivermectine tel que celui utilise par l'Alliance Globale pour l'Elimination de la Filariose Lymphatique. Se han continuado los esfuerzos para controlar la esofagostomiasis humana y la infeccion por uncinaria en el norte de Ghana, como seguimiento al estudio de Ziem et al. publicado en este numero. Los resultados se han evaluado en colaboracion con el Programa de Eliminacion de la Filariasis Linfatica. Esta fase de evaluacion del impacto del tratamiento masivo no se realizo a pequena escala, limitandose al entorno de un centro de investigacion: se realizo dentro del contexto de un programa nacional de control operativamente viable y como una continuacion del Proyecto de Investigacion Interventiva Oesophagostomum [Oesophagostomum Intervention Research Project (OIRP)]. Los metodos de evaluacion incluian el clasico examen de heces mediante la tecnica de Kato, cultivo de heces y examen con ultrasonido de la pared del colon. El tratamiento anual con albendazol–ivermectina de 11 poblaciones dispersas en el noroeste de Ghana y con una cobertura del 70–75%, resulto en una reduccion de la prevalencia de Oesophagostomum de aproximadamente el 20% antes de la intervencion a menos del 1% despues de dos anos de tratamiento masivo. Simultaneamente, la prevalencia de uncinaria disminuyo del 70% a aproximadamente 15%. Sin embargo, los datos no pueden compararse con aquellos de Ziem et al. debido a que el sistema de tamizaje que se debio utilizar para la evaluacion a gran escala de un programa de control era un tanto grosero: un unico cultivo de heces. En el area de estudio de la OIRP, la interrupcion del tratamiento masivo resulto en un aumento de la prevalencia de uncinaria. Por otro lado, la prevalencia de Oesophagostomum continuo disminuyendo. Pareceria que la transmision de la esofagostomiasis humana puede interrumpirse, al demostrarse que los pequenos numeros de casos persistentes de infeccion por Oesophagostomum eran insuficientes para servir como un nucleo que reactivase la dispersion de la infeccion. Los datos sugieren que tanto la infeccion como la patologia debida a la esofagostomiasis humana pueden eliminarse y que la eliminacion puede conseguirse a traves de un tratamiento operativamente factible con albendazol–ivermectina, tal y como se utiliza en la Alianza Global para la Eliminacion de la Filariasis Linfatica.

Related terms

Oesophagostomiasis - 15 days free trial to Access Experts & Abstracts