Surveillance of Leishmania spp., Assessment in Sand Flies and Rodents, and Intervention Measures Using Drones During an Outbreak of Cutaneous Leishmaniasis in Southern Israel.

BACKGROUND

Leishmania major and Leishmania infantum infection were evaluated in sand flies and rodents during a cutaneous leishmaniasis (CL) outbreak in two military camps in southern Israel (2022-2023). The efficacy of a novel intervention combining drone-based pesticide application and rodent bait stations was assessed.

METHODS

Sand flies and rodents were sampled and tested for Leishmania by PCR and DNA sequencing. In April 2023, precision spreading of pesticides via drones and bait stations targeting Meriones tristrami and Mus musculus domesticus was done in camp 2, while camp 1 served as control. Leishmania infection rates in vectors and reservoirs were compared before and after intervention, alongside CL incidence in soldiers.

RESULTS

A total of 7,204 female Phlebotomus papatasi were analyzed. The minimal infection rate of L. major in camp 2 declined from 1.23 in 2022 to 0.03 post-iinterventionin 2023 (p = 0.034). In camp 1, no significant change occurred (0.50 in 2022 vs. 0.22 in 2023, p = 0.622). Among 63 rodents, 8 (12.7%) were infected: five with L. infantum (2/11 M. musculus domesticus [18.2%] and 3/52 M. tristrami [6%]) and three M. tristrami (6%) with L. major. Overall rodent infection declined significantly from 24.1% in 2022 to 2.9% in 2023 (p = 0.032), with camp 2 showing the most pronounced reduction (31.6% vs. 3.3%, p = 0.02). Human CL incidence also dropped significantly: in camp 1, from 17.1 to 2.6/1000, and in camp 2, from 33.3 to 4.9/1000 (p < 0.001).

CONCLUSIONS

Significant reductions in Leishmania infection were observed in vectors, reservoirs, and humans following the intervention. Although CL dynamics are influenced by multiple factors, these findings support the potential of drone-based and host-targeted approaches for integrated leishmaniasis control. Further studies are required to validate and optimize such technologies.