Seasonal trends of sand fly abundance and Leishmania infection: The case of Bologna province, Italy (2016–2023)
Juthathip Khongpetch,
Giovenale Moirano,
Annalisa Grisendi,
Mara Scremin,
Giovanna Mattei,
Arianna Puggioli,
Paola Angelini,
Giulio Matteo,
Michele Dottori,
Milena Maule,
Mattia Calzolari
Affiliations
Juthathip Khongpetch
Cancer Epidemiology Unit, Medical Science Department, University of Turin and CPO Piemonte, Via Santena 7, 10126 Turin, Italy; University School for Advanced Studies IUSS Pavia, Palazzo del Broletto, Piazza della Vittoria, 27100 Pavia, PV, Italy; Corresponding author at: Cancer Epidemiology Unit, Medical Science Department, University of Turin and CPO Piemonte, Via Santena 7, 10126 Turin, Italy.
Giovenale Moirano
Cancer Epidemiology Unit, Medical Science Department, University of Turin and CPO Piemonte, Via Santena 7, 10126 Turin, Italy
Annalisa Grisendi
Laboratorio Entomologia Sanitaria, Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia-Romagna ''B. Ubertini'', Via Pitagora 2, 42124 Reggio Emilia, Italy
Mara Scremin
Laboratorio Entomologia Sanitaria, Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia-Romagna ''B. Ubertini'', Via Pitagora 2, 42124 Reggio Emilia, Italy
Giovanna Mattei
Regional Health Authority, Emilia-Romagna Region, 40127 Bologna, Italy.
Arianna Puggioli
Centro Agricoltura Ambiente “G. Nicoli”, Via Sant'Agata 835, 40100 Crevalcore, Italy.
Paola Angelini
Regional Health Authority, Emilia-Romagna Region, 40127 Bologna, Italy.
Giulio Matteo
Regional Health Authority, Emilia-Romagna Region, 40127 Bologna, Italy.
Michele Dottori
Laboratorio Entomologia Sanitaria, Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia-Romagna ''B. Ubertini'', Via Pitagora 2, 42124 Reggio Emilia, Italy
Milena Maule
Cancer Epidemiology Unit, Medical Science Department, University of Turin and CPO Piemonte, Via Santena 7, 10126 Turin, Italy
Mattia Calzolari
Laboratorio Entomologia Sanitaria, Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia-Romagna ''B. Ubertini'', Via Pitagora 2, 42124 Reggio Emilia, Italy
Leishmaniasis is a vector-borne disease, caused by Leishmania parasites, transmitted by phlebotomine sand flies. Recently, shifts in its geographic distribution have been observed across Europe, including Italy, with climate changes believed to influence sand fly proliferation, altering disease transmission. Using meteorological, entomological, and visceral leishmaniasis (VL) data (2016–2023) from the province of Bologna, Italy, this study aimed at examining the relationships between meteorological factors and sand fly abundance, Leishmania infection in sand flies, and human VL cases. Entomological data showed the peak of sand fly abundance in July–August, followed by a peak of the infection rate one month later. Sand fly abundance resulted negatively correlated with spring cumulative precipitation (r = −0.93, 95 % CI: −1.00, −0.62) and mean relative humidity (r = −0.81, 95 % CI: −1.00, −0.29) while a positive correlation was observed between yearly sand fly abundance and number of VL cases in the following year (r = 0.82, 95 % CI: 0.34, 1.00). A negative correlation was also found between cumulative precipitation from March to June and number of VL cases in the following year (r = −0.71, 95 % CI: −1.00, −0.07). These findings suggest that reduced precipitation may contribute to increased sand fly abundance within the same season and potentially lead to higher number of notified human VL cases in the following year. Our study highlights the importance of meteorological factors as potential predictors of leishmaniasis. Considering these findings, we propose that public health measures, such as information campaigns and the use of repellents, could be strengthened during drier years, provided that our results can be replicated in other regions with different environmental contexts to ensure broader applicability.
