Babesia spp. and Anaplasma phagocytophilum in questing ticks, ticks parasitizing rodents and the parasitized rodents – Analyzing the host-pathogen-vector interface in a metropolitan area

Particle and Fibre Toxicology

Martin Pfeffer¹  Monia Mahling³  Kurt Pfister²  Dietmar Hamel²  Dietlinde Woll¹  Cornelia Silaghi² 

[1] Institute of Animal Hygiene and Veterinary Public Health, University Leipzig, Leipzig, Germany;Comparative Tropical Medicine and Parasitology, Ludwig-Maximilians-Universität München, Munich, Germany;Statistical Consulting Unit, Department of Statistics, Ludwig-Maximilians-Universität München, Munich, Germany

关键词: Vector-host relation;    Host survey;    Recreational area;    Yellow-necked mouse;    Bank vole;    Dermacentor reticulatus;    Ixodes ricinus;    Anaplasma phagocytophilum;    Babesia spp;   

Others  :  1230116
DOI  :  10.1186/1756-3305-5-191

 received in 2012-04-05, accepted in 2012-08-07,  发布年份 2012

【 摘 要 】

Background

The aims of this study were to evaluate the host-tick-pathogen interface of Babesia spp. and Anaplasma phagocytophilum in restored areas in both questing and host-attached Ixodes ricinus and Dermacentor reticulatus and their small mammalian hosts.

Methods

Questing ticks were collected from 5 sites within the city of Leipzig, Germany, in 2009. Small mammals were trapped at 3 of the 5 sites during 2010 and 2011. DNA extracts of questing and host-attached I. ricinus and D. reticulatus and of several tissue types of small mammals (the majority bank voles and yellow-necked mice), were investigated by PCR followed by sequencing for the occurrence of DNA of Babesia spp. and by real-time PCR for A. phagocytophilum. A selected number of samples positive for A. phagocytophilum were further investigated for variants of the partial 16S rRNA gene. Co-infection with Rickettsia spp. in the questing ticks was additionally investigated.

Results

4.1% of questing I. ricinus ticks, but no D. reticulatus, were positive for Babesia sp. and 8.7% of I. ricinus for A. phagocytophilum. Sequencing revealed B. microti, B. capreoli and Babesia spp. EU1 in Leipzig and sequence analysis of the partial 16S RNA gene of A. phagocytophilum revealed variants either rarely reported in human cases or associated with cervid hosts. The statistical analysis revealed significantly less ticks infected with A. phagocytophilum in a city park in Leipzig as compared to the other sampling sites. A. phagocytophilum-DNA was detected in 2 bank voles, DNA of B. microti in 1 striped field-mouse and of Babesia sp. EU1 in the skin tissue of a mole. Co-infections were detected.

Conclusion

Our results show the involvement of small mammals in the natural endemic cycles of tick-borne pathogens. A more thorough understanding of the interactions of ticks, pathogens and hosts is the essential basis for effective preventive control measures.

【 授权许可】

   
2012 Silaghi et al.; licensee BioMed Central Ltd.

【 图 表 】

Figure 1 .

Figure 1 .

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