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Leishmaniasis is caused by protozoans of the Leishmania genus, which includes more than 20 species capable of infecting humans worldwide. In the Americas, the most widespread specie is L. braziliensis, present in 18 countries including Bolivia. The taxonomic position of the L. braziliensis complex has been a subject of controversy, complicated further by the recent identification of a particular subpopulation named L. braziliensis atypical or outlier. The aim of this study was to carry out a systematic analysis of the L. braziliensis complex in Bolivia and to describe the associated clinical characteristics. Forty-one strains were analyzed by sequencing an amplified 1245 bp fragment of the hsp70 gene, which allowed its identification as: 24 (59%) L. braziliensis, 16 (39%) L. braziliensis outlier, and one (2%) L. peruviana. In a dendrogram constructed, L. braziliensis and L. peruviana are grouped in the same cluster, whilst L. braziliensis outlier appears in a separate branch. Sequence alignment allowed the identification of five non-polymorphic nucleotide positions (288, 297, 642, 993, and 1213) that discriminate L. braziliensis and L. peruviana from L. braziliensis outlier. Moreover, nucleotide positions 51 and 561 enable L. peruviana to be discriminated from the other two taxa. A greater diversity was observed in L. braziliensis outlier than in L. braziliensis-L. peruviana. The 41 strains came from 32 patients with tegumentary leishmaniasis, among which 22 patients (69%) presented cutaneous lesions (11 caused by L. braziliensis and 11 by L. braziliensis outlier) and 10 patients (31%) mucocutaneous lesions (eight caused by L. braziliensis, one by L. braziliensis outlier, and one by L. peruviana). Nine patients (28%) simultaneously provided two isolates, each from a separate lesion, and in each case the same genotype was identified in both. Treatment failure was observed in six patients infected with L. braziliensis and one patient with L. peruviana.

[eng] Leishmaniasis is a group of diseases caused by an obligate protozoan Leishmania and transmitted by sand flies. As a neglected tropical disease (NTD), leishmaniasis disproportionately affects the poorest populations and those living in rural, remote areas or conflict zones with limited or no access to health care. Manifesting in cutaneous, mucocutaneous or visceral symptoms, the diseases’ complexity and diversity across regions contribute to the challenges in the control efforts. Visceral leishmaniasis (VL) is fatal without treatment, and the indelible scars left by cutaneous leishmaniasis (CL) may have important psycho-social impact. Eastern Africa region currently bears most of the world’s VL burden. However, underestimation of true disease burden is likely, as the paucity of data from unstable contexts may contribute to inaccurate disease estimates. Both VL and CL are known to have limited geographic distribution but may show high variability inter- and intra-countries. Population movement due to conflict or drought, combined with weak or poorly functioning health system have led to epidemics and spread in new areas. Without vaccine or effective vector control, the pillar of control strategy in Africa remains diagnosis and treatment. Access to adequate, quality diagnostic and treatment services in Africa is challenging. The rk39 rapid test is less accurate and treatment options are limited. A 17-day combination of antimonial and paromomycin is the first line treatment for VL in the region, requiring prolonged hospitalisation and increased economic burden for the patients and their households. Despite the progress in tackling NTDs, access to care for leishmaniasis is often taken for granted. Especially in Africa, access remains problematic and the current body of literature shows critical evidence gaps. Low coverage of the health services, accessibility and availability of quality care, limited diagnostic and therapeutic options along with inefficient procurement and supply remain significant challenges in the region. Delay in seeking treatment not only increase morbidity and mortality but also sustain transmission. The hypothesis informing the project is that access to care for leishmaniasis in Africa is still inadequate. The general objectives of this thesis are to improve our understanding on access to care in Africa, by documenting availability, affordability and accessibility of care, explore novel ways of enhancing such care, and provide insights into specific elements of access to formulate coherent policy recommendations for leishmaniasis in eastern Africa. Three specific objectives were formulated: the first is to update the disease burden, second to examine access issues ‘upstream' i.e. the R&D process and third, assess access issues ‘downstream’., [spa] La leishmaniasis es un grupo de enfermedades causadas por un protozoo (Leishmania) y transmitidas por flebótomos. Como enfermedad tropical desatendida (NTD, por sus siglas en inglés), la leishmaniasis afecta de manera desproporcionada a las poblaciones más pobres y a las personas que viven en zonas rurales, remotas o en zonas de conflicto con acceso limitado o nulo a la atención médica. Las distintas formas clínicas (cutánea, visceral), la complejidad y la distribución de la leishmaniasis en distintas regiones son algunos de los desafíos para controlar la enfermedad. La leishmaniasis visceral (LV) es mortal si el paciente no recibe tratamiento a tiempo, y las cicatrices dejadas por la leishmaniasis cutánea (LC) pueden tener un importante impacto psicosocial. Actualmente la mayor carga de LV se concentra en la región de África oriental aunque las cifras disponibles son probablemente una subestimación del número real de casos debido a la falta de datos fiables. Se sabe que tanto la LV como la LC tienen una distribución geográfica limitada, pero pueden mostrar una alta variabilidad tanto entre países como entre zonas en un mismo país. Los movimientos poblacionales debidos a conflictos o sequías, combinado con un sistema de salud débil o con un funcionamiento deficiente, provocan la expansión de la enfermedad a nuevas áreas y la aparición de epidemias. Al no existir una vacuna ni un control efectivo de vectores, el control de la leishmaniasis en África se sigue basando en el diagnóstico y el tratamiento de los casos. La hipótesis inicial de este proyecto es que es que el acceso al cuidado de la leishmaniasis en África sigue siendo inadecuado. Los objetivos generales de esta tesis son mejorar el conocimiento sobre el acceso a la atención de los casos de leihmaniasis en África, documentando la disponibilidad, la asequibilidad y la accesibilidad de los servicios sanitarios, explorar nuevas formas de mejorar dicha atención y formular recomendaciones de políticas de acceso al cuidado de la leishmaniasis en África oriental. Los tres objetivos específicos son: actualizar los datos sobre carga de enfermedad así como estudiar los problemas de acceso tanto a nivel de I+D como sobre el terreno.