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Anaplasma phagocytophilum and Babesia spp. are emerging tick-borne pathogens which can threaten human health. A duplex real-time PCR and qPCRs with primers and probes targeting 97 and 116 bp fragments of 16S rRNA and 18S rRNA genes, respectively, were used for qualitative and quantitative detection of both pathogens in Ixodes ricinus ticks. Altogether 1875 ticks (1084 adults and 791 nymphs) were collected from rural and urban habitats in northern Poland. Of them, at least 0.9 % were found to be infected with A. phagocytophilum while 2.5 % with Babesia spp. A comparison of the infection rates by the tick stage, the type of area, the collection site, habitats of different tick density and by the month of collection was done. The prevalence of pathogens was significantly lower in nymphs than in adult ticks ( p = 0.02) and in rural areas than in urban areas ( p = 0.007). Four different 16S rRNA gene variants of A. phagocytophilum were determine, however none of them showed 100 % identity with compared sequences isolated from human patients. The dominant Babesia species was B. venatorum. Results of qPCRs with circular and linearized forms of plasmids used as the standards showed significant difference in the pathogen loads ( p = 0.001). The copy numbers of A. phagocytophilum and Babesia spp. estimated from the linear plasmids were 28.7 and 5.1 times lower, respectively, when compared with their circular forms, and were accepted as more reliable. The average number of copies of 16S rRNA gene of A. phagocytophilum in the positive I. ricinus samples were 3.39 × 10 ± 6.09 × 10. The mean copy number of 18S rRNA gene of Babesia spp. was ~2.55 × 10 ± 1.04 × 10. We confirmed the presence of A. phagocytophilum and Babesia spp. in I. ricinus in both rural and urban environments. The determined low infection rates suggests, however, that the risk for local population and tourists to acquire infection is also low. Moreover, we confirmed recent findings that serious overestimation by circular plasmid DNA makes it less suitable as a standard and that the linear standards should be recommended for qPCR. [ABSTRACT FROM AUTHOR]

Abstract: Questing Ixodes ricinus ticks from different regions of Poland were investigated for the presence of spotted fever group (SFG) rickettsiae. A total of 1214 DNA samples of 2813 ticks, including 820 individual adult ticks and 394 pools containing 1993 nymphs, were tested by PCR for a fragment of the rickettsial gltA gene using the primers RpCs.877 and RpCs.1258. Overall, at least 5.5% ticks were found to be positive with the highest prevalence observed in females (10.6%). A sample of 14 positive PCR products was sequenced. Analyzed fragments of 270–370bp showed 100% similarities to corresponding sequences of Rickettsia helvetica deposited in the GenBank. Results of our investigation confirm the occurrence and wide distribution of R. helvetica in I. ricinus tick populations in Poland. This rickettsia should be added to the list of potentially dangerous pathogens transmitted by ticks in our country. [Copyright &y& Elsevier]

Abstract: Adult Ixodes ricinus ticks were collected from Pomerania province, northern Poland, to determine the presence of infection with agents of human granulocytic ehrlichiosis (HGE) and Lyme borreliosis by using the polymerase chain reaction (PCR). Of the 424 ticks 19.2% and 11.6% contained ehrlichiae and spirochetes, respectively. Frequency of single infection with the HGE agent was 63/424 while frequency of single infection with Borrelia burgdorferi sensu lato was 28/424. As many as 21/424 ticks (5%) contained both pathogens. This finding supports suggestions that both HGE agent and B. burgdorferi s. 1. perpetuate in the same foci and frequently co-infect the same tick vector thereby increasing the risk of humans acquiring mixed infection. [Copyright &y& Elsevier]