First isolation ofRickettsia helvetica fromIxodes ricinus ticks in France

Abstract

Two rickettsial isolates recovered from Ixodes ricinus ticks in Puy-de-Dôme (Central France) were characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, Western blot immunoassay, restriction fragment length polymorphism analysis, and sequencing of a portion of the citrate-synthase gene. By these methods, the isolates appeared to be identical to a member of the spotted fever group rickettsiae, Rickettsia helvetica. This first isolation of Rickettsia helvetica in France has epidemiologic importance; a serosurvey on Mediterranean spotted fever conducted previously in Puy-de-Dôme, where the infection is not endemic, demonstrated a high seroprevalence of nonspecific antibodies directed against spotted fever group rickettsiae lipopolysaccharides, and thus the possibility of infection due to a rickettsia different from Rickettsia conorii was suggested. The isolation of Rickettsia helvetica in anthropophilic ticks in the same area further supports this hypothesis.

Detection of Borrelia burgdorferi sensu lato and spotted fever group rickettsiae in hard ticks (Acari, Ixodidae) parasitizing bats in Poland

“…Their presence was confirmed by detection of the specific fragments of gltA and 16S rRNA gene, but no positive results were obtained when using primers targeting a fragment of the ompA gene. This suggested that detected rickettsiae belonged to the species R. helvetica as it is one of the few SFG rickettsiae in which ompA gene is not amplified (Roux et al 1996 ; Parola et al 1998 ). Further sequencing of gltA fragment enabled definitive identification.…”

Tick‐borne pathogens in ticks (Acari: Ixodidae) collected from various domestic and wild hosts in Corsica (France), a Mediterranean island environment

“…It was initially reported in 1979 in Switzerland from I. ricinus (Beati, Péter, Burgdorfer, Aeschlimann, & Raoult, 1993) and the species has now been identified in ticks from many countries worldwide. It is especially widespread in the Mediterranean area including in mainland France (Parola, Beati, Cambon, & Raoult, 1998), Italy (Beninati et al, 2002), Spain (Fernández-Soto, Pérez-Sánchez, Encinas-Grandes, & Sanz, 2004), Croatia (Dobec, Golubic, Punda-Polic, Kaeppeli, & Sievers, 2009), Algeria (Kernif et al, 2012) and Tunisia (Sfar et al, 2008). Human cases of rickettsiosis caused by R. helvetica have been reported in Italy and continental France (Portillo, Santibáñez, García-Álvarez, Palomar, & Oteo, 2015).…”

A prevalent alpha-proteobacterium Paracoccus sp. in a population of the Cayenne ticks (Amblyomma cajennense) from Rio de Janeiro, Brazil

“…In South America, Amblyomma cajennense is considered the most important tick species, representing the main vector of the Rhodobacteraceae Rickettsia rickettsii , the etiological agent of Rocky Mountain Spotted Fever (Sexton et al , 1993; Lemos 2000; Galvão et al , 2003; Guedes et al , 2005). A. cajennense may also harbor several other bacteria, such as Coxiella , Francisella and other Rickettsia species, which may represent new agents of human diseases or symbionts (Sexton et al , 1993; Parola et al , 1998; Machado-Ferreira et al , 2009, 2011). …”

“…Most were classified as tick symbionts, while others were considered EID agents (Parola et al , 1998; Fournier et al , 2000; Beninati et al , 2002; Nilsson et al , 2002). Many of the symbionts were further reclassified as pathogenic agents (Fournier et al , 2000; Nilsson et al , 2002).…”