Acta Tropica 115 (2010) 84–89 Contents lists available at ScienceDirect Acta Tropica journal homepage: www.elsevier.com/locate/actatropica Risk factors for Schistosoma haematobium infection and morbidity in two villages with different transmission patterns in Niger Amadou Garba a , Sébastien Pion b , Amandine Cournil b , Jacqueline Milet c , Dominique Schneider a,c , Gérard Campagne a , Jean-Philippe Chippaux a,c , Denis Boulanger a,b,* a Centre de Recherche Médicale et Sanitaire (CERMES, formerly Centre de Recherche sur les Méningites et les Schistosomoses), BP 10887, Niamey, Niger b Unité Mixte de Recherche 145, Institut de Recherche pour le Développement (IRD) and Université de Montpellier 1, Centre IRD de Montpellier, 911 avenue Agropolis, BP 64501, 34394 Montpellier Cedex 5, France c Institut de Recherche pour le Développement, Unité de Recherche 010, Faculté de Pharmacie, 4, Avenue de l’Observatoire, 75270 Paris, France article info Article history: Available online 18 February 2010 Keywords: Schistosoma haematobium Epidemiology Parasitology Morbidity Niger Transmission pattern abstract A better control of major neglected tropical diseases such as schistosomiasis is urgently needed to reduce their impact on public health in developing countries. To optimize the efficiency of intervention cam- paigns, we assessed the influence of individual human factors on the level of Schistosoma haematobium infection and morbidity in a typical Sahelian country (Niger). Random samples of 246 and 257 individuals were selected from general census in two villages with distinct patterns of schistosome transmission. One village (Lossa) is located in an area of perennial transmission whereas transmission is seasonal in the other village (Tara). Despite comparable levels of both egg excretion and lower tract pathology in the two villages, the inhabitants of Lossa had a higher risk (OR: 2.1, 95% CI: 1.1–3.9) of developing upper tract lesions compared to those living in Tara. In both villages, bladder lesions were more serious in males than in females. Children between 7 and 15 years old were the most at risk to experience heavy infections (OR: 3.4, 95% CI: 2.1–5.7), bladder (OR: 4.5, 95% CI: 2.6–7.8) and upper tract (OR: 10.4, 95% CI: 2.4–45.0) lesions, independently of gender and village. These results confirm that targeted intervention campaigns should include foci regardless of their schistosome transmission pattern and focus on the school-aged population. © 2010 Elsevier B.V. All rights reserved. 1. Introduction The control of neglected tropical diseases (NTDs) has become an internationally supported objective to sustainably reduce poverty (Ault, 2008). Integrated mass chemotherapy is currently being implemented in several parts of Africa as a common strategy against the most prevalent NTDs (Hotez et al., 2009). Although large-scale drug distributions have met with undoubtful success, the long-term cost-efficacy ratio of an approach based on cura- tive repeated treatments alone needs to be estimated (Garba et al., 2006). Therapeutic vaccination, delivered during ongoing infections, would be an alternative/complementary tool which could delay the need for periodic rounds of drug administration (Bergquist et al., 2008). * Corresponding author at: Unité Mixte de Recherche 145, Institut de Recherche pour le Développement (IRD) and Université de Montpellier 1, Centre IRD de Mont- pellier, 911, avenue Agropolis BP 64501, 34394 Montpellier Cedex 5, France. Tel.: +33 0 4 67 41 61 62; fax: +33 0 4 67 41 63 30. E-mail address: denis.boulanger@ird.fr (D. Boulanger). Sahelian countries have been long-lasting endemic areas for schistosomosis haematobia, a trematode infection which results in severe pathology affecting the uro-genital tract. Control of schis- tosomiasis relies on mass drug administration of praziquantel, the best drug against Schistosoma species. However given the limited effect of the drug on the infective and pre-adult stages of Schistosoma haematobium, reinfection occurs and treatments have to be repeated every year. Combining such treatment with a preventive vaccine would allow the drug to provide short-term reduction of the established pathology and the vaccine to confer long-term protective immunity against reinfections. The recombi- nant schistosome-derived enzymatic protein rSh28GST is, to date, the most advanced vaccine candidate (McManus and Loukas, 2008) and its synergy with praziquantel is under clinical investigation (Capron et al., 2005). Besides this, because mass campaigns remain difficult to imple- ment in developing countries (Tallo et al., 2008), the possibility of selectively targeting groups in the population who would benefit the most from the intervention should be considered. In schistoso- miasis, the burden of disease can be extrapolated from prevalence and intensity of infection data (van der Werf et al., 2003) but a more direct evaluation of the morbidity through the use of ultra- 0001-706X/$ – see front matter © 2010 Elsevier B.V. All rights reserved. doi:10.1016/j.actatropica.2010.02.007