Tick Species Diversity and Molecular Identification of Spotted Fever Group Rickettsiae Collected from Migratory Birds Arriving from Africa

Abstract

The role of migratory birds in the spread of ticks and tick-borne pathogens along their routes from Africa to Europe is increasingly emerging. Wild birds can host several tick species, often infected by bacteria responsible for zoonoses. The aim of the study is to assess the possible introduction of exotic ticks carried by migratory birds into Italy from Africa and to detect the presence of Rickettsia species and Coxiella burnetii they may harbor. During a two-year survey, we collected ticks from migratory birds captured during their short stop-over on Ventotene Island. Specimens were first identified by morphology or sequencing molecular targets when needed, and then tested by real-time PCR for the presence of selected pathogens. A total of 91% of the collection consisted of sub-Saharan ticks, more than 50% of which were infected by Rickettsia species belonging to the spotted fever group, mainly represented by R. aeschlimannii. In contrast, the suspected C. burnetii detected in two soft ticks were confirmed as Coxiella-like endosymbionts and not the pathogen. Although there are still gaps in the knowledge of this dispersal process, our findings confirm the role of migratory birds in the spread of ticks and tick-borne pathogens, suggesting the need for a continuous surveillance to monitor the potential emergence of new diseases in Europe.

Rickettsial Infection in the COVID-19 Era: The Correlation between the Detection of Rickettsia aeschlimannii in Ticks and Storytelling Photography of a Presumable Human Rickettsiosis Case

“…The ticks of the H. marginatum complex are characterized by a high ecological plasticity and they can be found in very different environments, including arid or humid pastures, in low, medium and high mountains or in the Mediterranean maquis. In Italy, adult and immature specimens of H. m. marginatum were historically reported in continental and insular regions, including the Apulia region [17][18][19]. H. marginatum is an exophilic and ditropic tick with a cycle of two hosts where only the larvae and adults need to find a host.…”