Abstract
There is limited information regarding the role of wild mammals in the transmission dynamics of Leishmania infantum. A potential human leishmaniasis hot spot was detected in southern Spain that could not be explained solely by canine leishmaniasis prevalence. The aim of this work was to analyse the involvement of wild rabbits as the main factor affecting this Mediterranean hot spot. A survey of wild rabbits, dogs and sand flies was conducted in the human cases environment. A nearby region without clinical leishmaniasis cases was used as reference control. 51 wild rabbits shot by hunters were analysed by molecular techniques. 1100 sand flies were captured and morphologically identified. Blood collected from patients’ relatives/ neighbours (n = 9) and dogs (n = 66) was used for molecular analysis and serology. In Mediterranean leishmaniasis hot spots such as Montefrío municipality (average incidence of 16.8 human cases per 100,000 inhabitants/year), wild rabbits (n = 40) support high L. infantum infection rates (100%) and heavy parasite burdens (average value: 503 parasites/mg) in apparently normal ear skin directly accessible to sand flies, enabling the existence of heavily parasitized Phlebotomus perniciosus females (12.5% prevalence). The prevalence of infection and median parasite load were very low among rabbits captured in Huéscar (n = 11), a human clinical leishmaniasis-free area for the last 18 years. P. perniciosus was the most abundant Phlebotomus species in all the domestic/peridomestic microhabitats sampled, both indoors and outdoors. Accordingly, leishmaniasis is clustering in space and time at this local scale represented by Montefrío due to the proximity of two competent host reservoirs (dogs and heavily parasitized wild rabbits) associated with overlapping sylvatic and domestic transmission cycles through the main vector, P. perniciosus. We highlight the usefulness of determining the prevalence of infection and parasite burden in wild rabbits as a control leishmaniasis measure with the advantage that the use of the ear offers.
Highlights
Leishmaniasis remains one of the world’s most devastating neglected tropical diseases
The domestic dog is the main reservoir of Leishmania infantum Nic olle, 1908, the causative agent of canine leishmaniasis (CanL) and a variety of human leishmaniasis (HumL) clinical manifestations in the Mediterranean basin
The average annual hospitalization rate in Spain for leishmaniasis ranged from 0.4 between 1999 and 2003 (Valcarcel et al, 2008), to 0.56 between 1997 and 2011 (Herrador et al, 2015). This increasing trend was re flected in a study over a 14-year period in southern Spain, where the annual incidence of autochthonous leishmaniasis increased from 0.12 per 100.000 inhabitants in 2003 to 3.93 in 2016 following a linear model (Martín-Sanchez et al, 2020)
Summary
Leishmaniasis remains one of the world’s most devastating neglected tropical diseases. The average annual hospitalization rate in Spain for leishmaniasis ranged from 0.4 between 1999 and 2003 (Valcarcel et al, 2008), to 0.56 between 1997 and 2011 (Herrador et al, 2015). This increasing trend was re flected in a study over a 14-year period in southern Spain, where the annual incidence of autochthonous leishmaniasis increased from 0.12 per 100.000 inhabitants in 2003 to 3.93 in 2016 following a linear model (Martín-Sanchez et al, 2020). Underreporting and underdiag nosis have been found, in cutaneous leishmaniasis (Mer ino-Espinosa et al, 2018)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.