Coxiellaceae in Ticks from Human, Domestic and Wild Hosts from Sardinia, Italy: High Diversity of Coxiella-like Endosymbionts

Abstract

Purpose Coxiella burnetii is known for its potential as veterinary and human bacterial pathogen. The bacteria have been described in ticks, but their role in transmission of Q fever in humans is considered low. Coxiella endosymbionts closely related to C. burnetii have been also isolated from an extensive range of tick species and evidence is growing that these endosymbionts could be linked to human bacteremia. The aim of this study was to get new information on the presence of Coxiella species in ticks infesting wild and domestic hosts in Sardinia, Italy. Methods Here, 138 ticks collected from the study area were analyzed for the presence of C. burnetii and Coxiella-like bacteria by polymerase chain reaction (PCR), sequencing and philogenetic analyses using a set of primers targeting the 16S rRNA gene. Results DNA of Coxiella species was detected in 69% of the total ticks examined. Based on phylogenetic analysis, the 16S rRNA Coxiella genotypes identified in this study grouped in strongly supported monophyletic clades with identified reference sequences of CLEs detected from Rhipicephalus, Dermacentor, Haemaphysalis and Ornithodoros species and with Coxiella burnetii strains isolated worldwide. Conclusion This study reports the molecular detection of a high diversity of Coxiella-like bacteria in Sardinian ticks and confirms also the presence of C. burnetii in tick species previously identified in the island. The role that Coxiella-like endosymbionts play in Sardinian ticks and in their vertebrate hosts needs to be explored further.

Profiles of Microbial Community and Antibiotic Resistome in Wild Tick Species

“…2B ). The two genera are potential human pathogens, and they have been demonstrated worldwide in ticks; however, all of them contained several nonpathogenic strains as well ( 21 , 22 ). They also play roles in B vitamins biosynthesis and the transmission of tick-borne pathogens ( 14 ).…”

Serological Evidence of Q Fever among Dairy Cattle and Buffalo Populations in the Campania Region, Italy

“…Serological evidence in humans, domestic ruminants, exposed workers (veterinarians, farmers, and slaughterhouse workers), pets, wildlife, and zoo animals has been described in Italy, as well as molecular evidence in humans, several mammals, birds, ticks (some of which can transmit the infection to humans), in the environment (urban river water), milk, and milk products [35][36][37][38][39][40][41][42]. Given the relevant presence of Q fever in the Italian eco-systems, disease control strategies would be critical to prevent or better manage potential outbreaks.…”

First serological record of Coxiella burnetii infection in the equine population of Slovakia

“…Coxiella burnetii has been considered to be the only species of the Coxiella genus. However, there is evidence that Coxiella-like (CL) organisms have a high homology with the pathogenic C. burnetii, based on the 16S rRNA sequence phylogenetic analyses (Gottlieb et al 2015;Trinachartvanit et al 2018), and they are widespread in ticks (Rahal et al 2020;Chisu et al 2021). In Slovakia, nonpathogenic CL microorganisms have been registered in ticks (Špitalská et al 2018).…”