Rickettsia asembonensis in fleas from wild and domestic hosts in Italy

This study provides the first molecular evidence and surveillance data of <i>Rickettsia asembonensis</i> in Sardinia, Italy, detected in fleas (<i>Pulex irritans, Xenopsylla cheopis</i>, and <i>Archaeopsylla erinacei</i>) collected from domestic (goat, dog, cat, and pig) and wild (wild boar, fox, kestrel, crow, pigeon, peacock, buzzard, hen, barn owl, martin, hedgehog, owl, and flamingo) hosts in Sardinia between 2021 and 2024. Multilocus molecular analyses of <i>gltA, ompA, ompB, Sca4</i>, and <i>htrA</i> genes revealed sequences with 100% identity to <i>R. asembonensis</i> strains previously reported from Brazil, Peru, Argentina, Thailand, and Malaysia, while all lice examined tested negative. These findings broaden current understanding of <i>Rickettsia</i> diversity in the Mediterranean region and highlight the importance of integrated surveillance involving diverse ectoparasite species. Sustained molecular monitoring of fleas and their hosts will be vital to clarify the ecology, distribution, and potential zoonotic relevance of <i>R. asembonensis</i> and other emerging <i>Rickettsia</i> species in southern Europe.