RT Journal Article T1 Twenty-year evolution of Leishmania infantum infection in dogs in Valdeorras (Galicia, Northwestern Spain): implication of climatic factors and preventive measures A1 Olmeda García, Patricia A1 Díaz-Regañón Fernández, David Rafael A1 Villaescusa Fernández, Alejandra A1 Amusátegui Amusátegui, Inmaculada A1 García, Adolfo A1 Herrero, Francisco A1 Tesouro, Miguel A. A1 Rodríguez Franco, Fernando A1 García-Sancho Téllez, Mercedes Guadalupe A1 Martín Fraile, Daniel A1 Sainz Rodríguez, Ángel AB Background: Abiotic factors play a significant role in the evolution of Leishmania infantum infection due to its vectorial nature. This study aims to assess the evolution in the detection of new L. infantum infection cases in Valdeorras (Ourense, Northwestern Spain) over a 20-year period and how different climatic variables and preventive measures may have affected it.Methods: Indirect immunofluorescence antibody tests (IFAT) were performed on serum samples collected from dogs attending the ‘Servicios Veterinarios de Sil’ veterinary clinic (Valdeorras, Northwestern Spain) between May 2003 and April 2023 to detect L. infantum exposure. The percentage of new cases of L. infantum infection was calculated from May of one year to April of the following year. Climatic conditions in the region, global sales of ectoparasiticides and the number of vaccines against L. infantum delivered in the veterinary clinic from 2003 to 2022 were recorded. Statistical analyses were conducted to determine the associations between these factors and the percentage of new cases of L. infantum infection.Results: A total of 2909 dogs were assessed, and 3785 IFAT tests were performed between May 2003 and April 2023. The mean percentage of new seropositive cases over the 20-year period studied was 21.65 ± 10.8%, with a decline from the beginning to the end of the period studied. The percentage was significantly higher between May 2003 and April 2008 compared with the other periods (May 2008 to April 2013, May 2013 to April 2018 and May 2018 to April 2023). There was a positive correlation between the percentage of new cases of L. infantum infection and the maximum relative humidity in winter. Conversely, there was a negative correlation between the percentage of new cases and sales of ectoparasiticides and vaccination against L. infantum.Conclusions: This study is one of the longest evaluations of the evolution of L. infantum infection in a fixed location and its association with external factors including climatic conditions and preventive measures. The results confirm that Valdeorras is a high-risk area for L. infantum infection. The use of ectoparasiticides and vaccines against L. infantum has been shown to play a significant role in preventing L. infantum infection, highlighting the crucial role of veterinarians in the fight against this disease. PB BMC YR 2024 FD 2024-07-01 LK https://hdl.handle.net/20.500.14352/106088 UL https://hdl.handle.net/20.500.14352/106088 LA eng NO Olmeda, P., Díaz-Regañón, D., Villaescusa, A. et al. Twenty-year evolution of Leishmania infantum infection in dogs in Valdeorras (Galicia, Northwestern Spain): implication of climatic factors and preventive measures. Parasites Vectors 17, 281 (2024). https://doi.org/10.1186/s13071-024-06357-8 NO Ministerio de Universidades (España) DS Docta Complutense RD 3 ago 2024