1. a Natural Resources Institute , University of Greenwich at Medway , Central Avenue, Chatham Maritime , Kent , ME4 4TB , UK
2. b Scharpenbergsweg 8, 21149 , Hamburg , Germany
3. c African Programme for Onchocerciasis Control (WHO-APOC) , 01 BP 549 , Ouagadougou 01 , Burkina Faso
4. d Departament de Microbiologia i Parasitologia Sanitaries , Universitat de Barcelona , C/Casanova 146, 08036 , Barcelona
5. e Agencia Española de Cooperación Internacional , Madrid , Spain
6. f Onchocerciasis Control Programme , Ministry of Health & Social Welfare (Ministerio de Sanidad y Bienestar Social) , Malabo , Equatorial Guinea
7. g Noguchi Memorial Institute for Medical Research , University of Ghana , PO Box LG581 Legon, Accra , Ghana