Patogenicidad y virulencia de Crithidia mellificae y Lotmaria passim y nueva descripción del morfotipo haptomona en Apis mellifera iberiensis

Abstract

Trypanosomatids are a large group of parasitic protozoa of greathuman and veterinary importance. Two groups, Leishmania and Trypanosoma, are the causative agents of very serious diseases in humans and other animal species, such as leishmaniosis, Chagas disease and sleeping sickness. They are therefore widely studied organisms. However, most of the species of the family Trypanosomatidae have been described colonising the digestive tract of insects, and although most of them are considered to be non-pathogenic for these hosts, trypanosomatids infecting bees and bumblebees seem to be an exception. In this thesis, basic aspects of pathogenicity and virulence of these organisms have been studied to understand their true impact on bee health,both at the colony and individual levels. For the first time, the prevalence of these organisms in bee colonies in Castilla-La Mancha has been determined for two time periods (2013-2014, and 2019, 2020 and 2021), in what is the most extensive study in Spain to date. For this purpose, a new RT-qPCR technique has been developed, allowing not only the efficient identification of three species of trypanosomatids in honeybee colonies but also the quantification of the parasite load, even at low levels of parasitism, constituting an efficient and reliable tool for the analysis of field samples. Using molecular identification techniques, trypanosomatids have been detected in colonies in all provinces of the region, with L. passim being the most prevalent species, C. mellificae being detected on some occasions and C. bombi on none...