The spotted fever group of Rickettsiae is a heterogeneous group of Rickettsiae transmitted by ticks, causing similar diseases in humans (spotted fever). Until recently, it was supposed that a single pathogenic tick-borne SFG Rickettsia circulated in each different geographic area and that R. conorii subsp. conorii was the SFG Rickettsiae circulating in Italy, but in the last decade, thanks to molecular diagnostic, several different Rickettsia species, previously not considered pathogenic for decades, have been isolated from ticks and definitively associated to human disease, also in Italy. The present survey was carried out with the aim of investigating the presence of different SFG Rickettsia species in a geographic area where no information was available. Ticks collected from animals submitted to necropsy, removed from humans in local hospitals and collected from the environment were identified and tested by PCR for Rickettsia spp. based on the gltA gene, and positive PCR products were sequenced. A total of 3286 ticks were collected. Fifteen tick species were recognized, the most represented (79.52%) species in the collection was Ixodes ricinus, followed by Rhipicephalus sanguineus (9.13%). The overall prevalence of Rickettsia infection was 7.58%. Eight species of Rickettsia were identified, the most frequent was R. monacensis (56%), followed by R. helvetica (25.50%). Noteworthy, is the detection in the present study of Rrhipicephali, detected only twice in Italy. These are the first data available on SFG Rickettsiae circulation in the study area and they can be considered as starting point to assess the possible risk for humans.

Rapid urbanisation and environmental changes are reshaping mosquito population dynamics and the transmission of vector-borne pathogens. Culex pipiens and Aedes albopictus have successfully adapted to anthropogenic environments, becoming key vectors of emerging and re-emerging arboviruses and filarial parasites. This study conducted a comparative entomological and pathogen surveillance between 2022 and 2023 in central Italy and Crete to assess species composition, population dynamics, and circulation of arboviruses and filarial nematodes across different ecological contexts.In Italy, a total of 22,757 mosquitoes were collected, with Cx. pipiens (~86%) and Ae. albopictus (~12%) being the predominant species. Significant temporal variations in mosquito diversity and frequency were observed. In 2022, molecular screening detected Usutu Virus (USUV) in Cx. pipiens in Central Italy, with the first report of co-circulation of USUV and Setaria nematodes. In 2023, co-circulation of West Nile Virus (WNV lineage 2) and USUV was identified in Cx. pipiens from the Marche region.In Crete, 791 mosquitoes were collected, with Culex species dominating the assemblages. The highest mosquito biodiversity was recorded in peri-urban areas, exhibiting temporal variation. Molecular screening detected Dirofilaria repens in Ae. albopictus. No evidence of WNV or USUV circulation was found.We provide a novel regional-scale approach by comparing two ecologically distinct Mediterranean regions. The findings underscore how environmental and ecological factors shape vector-pathogen interactions, and in particular biodiversity distribution, highlighting the need for targeted, region-specific mosquito surveillance and control strategies.