Until recently, the infections of humans with representatives of the genus Oesophagostomum were thought to be rare and of zoonotic origin. In the 19805, it was recognised that intense transmission... Show moreUntil recently, the infections of humans with representatives of the genus Oesophagostomum were thought to be rare and of zoonotic origin. In the 19805, 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. Show less
A field study was performed to examine suffering and treatment seeking from the perspective of children aged 816 years living in war-affected northern Uganda. Various techniques for collecting... Show moreA field study was performed to examine suffering and treatment seeking from the perspective of children aged 816 years living in war-affected northern Uganda. Various techniques for collecting qualitative and quantitative data were used, including a semi-structured questionnaire about illness experiences and medicine use over a 1-month recall period. The 165 children who were interviewed were attending primary schools for displaced children and/or commuters' night shelters. The children frequently attributed their common febrile ailments to malaria and used a variety of pharmaceuticals and herbal remedies, as self-medication, for their self-diagnosed malarial episodes. Misdiagnosis of febrile illnesses by the children (as well as by the local healthcare providers) and frequent misuse of medicines in the treatment of these illnesses appeared to be very common. Improvement of the health conditions of these children requires a change of focus. Firstly, children above the age of 5 years who are not under adult care and who are often no longer welcome in the local hospital's paediatric ward need to be accepted at the outpatient clinics currently intended for adults. Secondly, the local diagnostic system needs to be improved, not only so that malaria can be reliably diagnosed but also so that alternative diagnoses can be confirmed or rejected, otherwise the current over-consumption of antimalarial drugs may simply be replaced with an over-consumption of antibiotics. Show less
Verweij, J.J.; Canales, M.; Polman, K.; Ziem, J.; Brienen, E.A.T.; Polderman, A.M.; Lieshout, L. van 2010
Intestinal schistosomiasis is a disease caused by the tre-Schistosoma mansoni (Sambon, 1907). Man is the principal final host of this parasitic worm and the intermediate host is a fresh water snail... Show moreIntestinal schistosomiasis is a disease caused by the tre-Schistosoma mansoni (Sambon, 1907). Man is the principal final host of this parasitic worm and the intermediate host is a fresh water snail. The adult worms, which are some 8-15 mm long, inhabit the portal venous system. There, the females produce large amounts of eggs, many of which are excreted with the faeces. The remaining eggs get stuck in the tissues where they die. As a result of the dead eggs bilharzial granulomas are formed which are the main cause of pathologie changes in the host. The excreted eggs hatch on immersion in water and the escaping miracidia can freely live in the water for several hours. If they succeed in penetrating an intermediate host snail (in Ethiopia; Biomphalaria pfeifferi) a mother sporocyst, several daughter sporocysts, and eventually, after some 4-5 weeks, many cercariae are produced, The phase of asexual multiplication in the snail host results in the production of large numbers of exclusively either male or female cercariae. Only snails that have been penetrated successfully by several miracidia may shed cercariae of both sexes. The free living cercariae have a short life span: most of them die within 24 hours. Man may become infected when his skin is exposed to water containing cercariae. When the cercariae penetrate man's skin they are transformed into schistosomules and in some 40-60 days these schistosomules develop into adult worms that migrate to the portal and mesenteric veins. Then eggs are produced again. Show less
