These changes are an opportunity to redistribute roles within the health district in a more transparent and efficient fashion. ?? abstract in French | Spanish ?? text in English ?? pdf in English ?? 2015 World Health OrganizationAvenue Appia 20, 1211 Geneva 27, Switzerland, Fax.: +41 22 791 4894, Geneva, Genebra, CH, 1211, 41 22 791 4894bulletin@who.int