Epidemiological study of domestic and wild reservoirs of Leishmania infantum under a One Health approach

• Autores: Jesús Barbero Moyano
• Directores de la Tesis: Ignacio García Bocanegra (dir. tes.), Maria De Los Angeles Risalde Moya (dir. tes.), Moisés Gonzálvez Juan (dir. tes.)
• Lectura: En la Universidad de Córdoba (ESP) ( España ) en 2026
• Idioma: inglés
• Tribunal Calificador de la Tesis: Guadalupe Miró Corrales (presid.), Álvaro Martínez Moreno (secret.), Carla Maia (voc.)
• Programa de doctorado: Doctor en Programa Oficial de Posgrado en Biociencias y Ciencias Agroalimentarias
• Materias:
  • Ciencias agrarias
    • Ciencias veterinarias
  • Ciencias médicas
    • Epidemiología
• Enlaces
  • Tesis en acceso abierto en: Helvia
• Resumen

  • Leishmaniosis is a vector-borne zoonosis of global public health importance. In Europe, Leishmania infantum is the main species and its epidemiology is driven by a complex wildlife–domestic–human interface. Beyond dogs, the primary reservoirs, the role of other animals remains poorly understood. Therefore, the main objective of this doctoral thesis was to understand the role of different domestic and wild animal species in the epidemiology of L. infantum. Thus, Chapter 1 provided a holistic assessment of L. infantum epidemiology in Castro del Río (Andalusia, southern Spain). Widespread exposure was detected in wild lagomorphs (100%, 41/41; 95%CI: 94.1–100%), with high homology between sequences obtained from lagomorphs and sand flies. Entomological surveillance revealed a high frequency of DNA parasite detection, seasonal activity peaks, and opportunistic feeding behavior. Spatial clustering of L. infantum positivity near lagomorph hunting areas supported their role as reservoirs. Additionally, seropositivity in humans (6.2%; 9/145; 95%CI: 2.3–10.1) and exposure in domestic dogs (73.2%; 30/41; 95% CI: 59.6–86.7) were detected. These results underscore the importance of One Health–based surveillance in endemic areas. Chapter 2 evaluated L. infantum seroprevalence in equine species across western Europe. Overall seroprevalence was 9.8% (133/1,364; 95%CI: 8.2–11.3). Donkeys (27.9%) and mules/hinnies (21.8%) showed significantly higher seropositivity than horses (4.0%). These findings demonstrate the potential role of equids as domestic reservoirs of L. infantum. Chapter 3.1 evaluated L. infantum exposure in captive non-human primates in Spain. Anti-Leishmania antibodies were detected in 4.0% of animals (10/252; 95%CI: 1.6–6.4), while parasite kDNA was identified in hair samples from 62.8% (49/78; 95%CI: 52.1–73.6). Age and body size were identified as risk factors. In line, Chapter 3.2 evaluated L. infantum seroprevalence and associated risk factors in different zoo-kept species in Spain. Anti-L. infantum antibodies were detected in 5.1% of animals (22/429; 95%CI: 3.0–7.2). Both Chapter 3.1 and 3.2 demonstrated a widespread circulation of L. infantum in zoo-kept animals from Spain, emphasizing concerns for animal health, conservation, and public health. Chapter 4.1 evaluated L. infantum exposure in wild rabbits (Oryctolagus cuniculus) and Iberian hares (Lepus granatensis) in southern Spain. Overall exposure was 56.4% (356/631; 95%CI: 52.3–60.3). Phylogenetic analysis revealed high homology between the L. infantum sequences obtained and strains previously isolated from humans in Spain. The multivariable analysis identified meso-Mediterranean climate and the presence of goats as risk factors. Complementing the above, Chapter 4.2 evaluated the dynamics of L. infantum seropositivity in wild rabbits from Andalusia and the potential spatial and temporal risk factors associated during five consecutive periods. Homogeneous seroprevalence was detected in wild rabbit populations during the study period. Two significant spatial clusters of L. infantum seropositivity were identified. Both Chapter 4.1 and Chapter 4.2 reinforce the role of wild lagomorphs as natural L. infantum reservoirs in southern Spain. Chapter 4.3 evaluated L. infantum circulation in Iberian lynxes (Lynx pardinus) in the Iberian Peninsula. Overall exposure was 10.2% (80/783; 95%CI: 8.1–12.3). High homology with human and lagomorph strains was observed. Habitat and age were identified as risk factors. Our results suggest the potential role of Iberian lynxes as L. infantum spillover hosts. Chapter 4.4 investigated L. infantum, Bartonella spp. and Hepatozoon spp. circulation in anthropized rodents in Spain. Leishmania infantum and Bartonella spp. were detected in 4.9% (95%CI: 2.6–7.2) and 3.2% (95%CI: 1.3–5.0) of rodents, respectively, with zoonotic Bartonella strains identified, whereas Hepatozoon spp. was not detected. These findings indicate that rodents may contribute to the maintenance and transmission of some vector-borne pathogens in Spanish anthropized areas. This doctoral thesis provides comprehensive evidence on the role of multiple domestic and wild species in the L. infantum epidemiology, highlighting the importance of adopting a One Health approach against leishmaniosis.