Retrospective Analysis of Leishmaniasis in Sicily (Italy) from 2013 to 2021: One-Health Impact and Future Control Strategies

Abstract

Leishmaniasis is an important vector-borne disease that represents a serious public health problem, including in Sicily (Italy), which is considered an endemic area. We collected canine, feline and human data from 2013 to 2021 in Sicily, while entomological surveys were conducted only in 2013 and 2021. Overall, 23,794/74,349 (34.4%) of dogs and 274/4774 (11.8%) of cats were positive in one or more diagnostic tests. A total of 467 cases of human Leishmaniasis were reported, with 71% showing cutaneous and 29% visceral involvement. The provinces with the largest number of patients were Agrigento (45.4%) and Palermo (37%). In 2013, Phlebotomus perfiliewi was the dominant sandfly species in Sicily (68.7%), followed by Phlebotomus perniciosus (17.2%) and Sergentomya minuta (14%). In 2021, Phlebotomusperfiliewi was confirmed as the most common species (61.6%), followed by Phlebotomusperniciosus (33.1%) and Sergentomyaminuta (4.7%). Of particular interest was the identification of Phlebotomus papatasi (0.41%) in Agrigento. Our retrospective study can inform health authorities for the development of appropriate screening, treatment and control strategies to reduce Leishmania incidence rate. This study examined the present state of Leishmaniasis control, surveillance, and prevention in Sicily, but also highlighted deficiencies that could be addressed through the application of One-Health principles.

Keywords: Leishmaniasis; Leishmaniasis epidemiology; One-Health; canine Leishmaniasis; diagnosis; feline Leishmaniasis; human Leishmaniasis; sandflies.

Figure 1

Annual trend and prevalence of CanL and FeL in Sicily, from 2013 to 2021. (a) Histogram showing the percentage of positive dogs between 2013 and 2021. (b) Histogram showing the percentage of positive cats between 2013 and 2021.

Figure 2

Mean prevalence of CanL by Sicilian province. The spatial distribution of mean prevalence (%) from 2013 to 2021. The map generated with geographic information system (GIS) technology (MapInfo^® professional 17.0) software.

Figure 3

Human Leishmaniasis in Sicily. (a) Number of patients and incidence rates of cutaneous and visceral Leishmaniasis in Sicily, from 2013 to 2021. The histogram shows the incidence rates of CL and VL cases (per 100,000 pop) between 2013 and 2021 (Source: ISTAT). (b) Proportion of cutaneous and visceral Leishmaniasis by sex from 2013 to 2021, p-value < 0.0001. (c) Proportion of CL by age group from 2013 to 2021. (d) Proportion of VL cases by age group, p-value < 0.0001.

Figure 4

Number of VL and CL patients in provinces of Sicily. This image presents the spatial distribution of human case counts from 2013 to 2021. Map generated with Excel Power Map.

Figure 5

Proportion of sandfly species by Sicilian provinces. (a) Phlebotomus species collected during 2013 year; and (b) Phlebotomus species collected during 2021 year.