Leishmania tarentolae and Leishmania infantum in geckos from Mallorca Island, Spain

Abstract

Leishmania tarentolae and Leishmania infantum are two sympatric parasites of significant ecological and epidemiological interest in the Mediterranean basin. This study investigated the prevalence of L. tarentolae and L. infantum in two gecko species (Tarentola mauritanica and Hemidactylus turcicus) present on Mallorca Island, Spain, using duplex quantitative PCR. A total of 59 geckos were sampled across the island, including 53 T. mauritanica and six H. turcicus. Tissue and blood samples were screened for both parasites, and generalized linear models were used to assess organ-specific infection patterns. The results revealed the prevalence of Leishmania infection in adult T. mauritanica, with 10/49 (20.41%) testing positive for L. tarentolae and with 1/49 (2.04%) for L. infantum. Coinfection with both parasites was detected in 3/49 geckos (6.12%). No positives were identified in H. turcicus, probably due to small sample size. Regarding positivity by tissues, coleomic organs were more likely to be positive for L. tarentolae in adult T. mauritanica than blood, with a slighter positivity in the liver, spleen and lung. Interestingly, L. infantum was detected more frequently coinfecting with L. tarentolae than as a single parasite. These prevalence rates and the existence of coinfections highlight potential ecological interactions between the two parasites and reptiles. This study provides valuable data on the potential role of geckos in endemic areas like Mallorca. Author SummaryLeishmaniosis is a zoonotic disease caused by parasites that can infect both animals and humans. In Europe, Leishmania infantum is the main species responsible for the disease, with dogs acting as its primary host. However, recent research suggests that other animals, including reptiles, might also play a role in their spread. In this study, centered in wild geckos from Mallorca Island (Spain), we investigated the prevalence of L. tarentolae and L. infantum in two gecko species (Tarentola mauritanica and Hemidactylus turcicus). Using quantitative PCR, it was found that 14/49 (28.57%) of adult Tarentola mauritanica were positive for Leishmania parasites, 13/49 (26.53%) for L. tarentolae and 74/49 (8.16%) for L. infantum. Additionally, coinfection of both parasites was detected in three geckos (3/49, 6.12%). The second gecko species studied, Hemidactylus turcicus, was not positive for Leishmania, possible due to a small sample size. These results reinforce previous studies suggesting that geckos may carry both parasites. Since L. tarentolae has also been detected in dogs, and both Leishmania species are sympatric, it raises questions about the role of reptiles in leishmaniosis cycle and transmission, as well as the reliability of current diagnostic tests in coinfections of closely related parasite species.