Prevalence and molecular characterization of Rickettsia spp. in questing ticks from north-western Spain
Tick-borne rickettsioses, most of them belonging to the spotted fever group (SFG), have been recognized as important emerging vector-borne zoonotic diseases. In order to determine the presence of Rickettsia spp. in questing ticks from north-western Spain, 1056 Ixodes ricinus, 19 Dermacentor marginatus, 17 Dermacentor reticulatus and one Ixodes acuminatus were processed. Rickettsia DNA was detected by PCR targeting rOmpA and rOmpB genes. A total of 219 (20.7%) I. ricinus, 19 (100%) D. marginatus and four D. reticulatus (23.5%) were positive. The prevalence was significantly higher in I. ricinus from coastal areas and in winter. Five species were identified: Rickettsia felis, Rickettsia monacensis, Rickettsia raoultii, Rickettsia slovaca and “Candidatus Rickettsia rioja”. Our results reveal a significant presence of some pathogenic Rickettsia species in questing tick populations from this area which involves a noticeable risk of rickettsiosis. As R. raoultii, R. slovaca and “Ca. R. rioja” DNA were identified in I. ricinus, considered an unusual vector for these Rickettsia species, further studies are needed to unravel the role of that tick species in the maintenance and transmission of these three Rickettsia species in north-western Spain.
KeywordsRickettsia Dermacentor Ixodes Tick-borne diseases Spain Zoonoses
This research was supported by the Programme for Consolidating and Structuring Competitive Research Groups (GRC2015/003; Xunta de Galicia, Spain) and by a predoctoral grant (European Social Fund, Secretaría Xeral de Universidades, Xunta de Galicia, Spain).
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
- Burri C, Dupasquier C, Bastic V, Gern L (2011) Pathogens of Emerging Tick-Borne Diseases, Anaplasma phagocytophilum, Rickettsia spp., and Babesia spp., in Ixodes ticks collected from rodents at four sites in Switzerland (Canton of Bern). Vector Borne Zoonotic Dis 11:939–944CrossRefPubMedGoogle Scholar
- Ibarra V, Portillo A, Santibáñez S, Blanco JR, Pérez-Martinez L, Márquez J et al (2005) DEBONEL/TIBOLA—is Rickettsia slovaca the only etiological agent? Rickettsioses: from genome to proteome, pathobiology, and Rickettsiae as an international threat. Ann N Y Acad Sci 1063:346–348CrossRefPubMedGoogle Scholar
- Milhano N, Lopes de Carvalho I, Alves AS, Arroube S, Soares J, Rodriguez P, Carolino M, Núncio MS, Piesman J, de Sousa R (2010) Coinfections of Rickettsia slovaca and Rickettsia helvetica with Borrelia lusitaniae in ticks collected in a Safari Park. Portugal. Ticks Tick-borne Dis 1(4):172–177CrossRefPubMedGoogle Scholar
- Palomar AM, Portillo A, Mazuelas D, Roncero L, Arizaga J, Crespo A et al (2016) Molecular analysis of Crimean-Congo hemorrhagic fever virus and Rickettsia in Hyalomma marginatum ticks removed from patients (Spain) and birds (Spain and Morocco), 2009–2015. Ticks Tick Borne Dis 7:983–987CrossRefPubMedGoogle Scholar
- Pérez-Eid C (2007) Les tiques. Identification, biologie, importance médicale et vétérinaire. Lavoisier TEC & DOC, ParisGoogle Scholar
- Petney TN, Pfäfffie MP, Skuballa JD (2012) An annotated checklist of the ticks (Acari: Ixodida) of Germany. Syst Appl Acarol 17:115–170Google Scholar
- R Core Team (2018) R: A Language and Environment for Statistical Computing. https://www.R-project.org/
- Rizzoli A, Silaghi C, Obiegala A, Rudolf I, Hubálek Z, Földvári G et al (2014) Ixodes ricinus and its transmitted pathogens in urban and peri-urban areas in Europe: new hazards and relevance for public health. Front Public Health 1:251Google Scholar
- Santibáñez S, Portillo A, Palomar AM, Santibáñez P, Oteo JA (2017) Rickettsia spp. detected in Dermacentor marginatus from DEBONEL/TIBOLA/SENLAT patients. ESCCAR-ASR Joint meeting. International congress on Rickettsiae and other intracellular bacteria. Marseille, France. P1-20Google Scholar