Prevalence of borreliae in ixodid ticks from a floodplain forest ecosystem.
Host-seeking ixodid ticks were sampled in a floodplain forest ecosystem along the lower reaches of the Thaya (Dyje) river in South Moravia (Czech Republic) and Lower Austria during the period 1989-2002. The ticks were examined by dark-field microscopy for borreliae (Borrelia burgdorferi sensu lato, the agent of Lyme borreliosis), and attempts were made to culture the spirochetes in BSK-H medium from preparations containing their high numbers. Isolated borreliae were identified by PCR-RFLP analysis using probes directed against ribosomal spacer genes. A total of 797 nymphal and 719 adult (391 female, 328 male) Ixodes ricinus were examined: 16.2% of nymphs, 28.6% of females and 29.0% of males were positive. Dermacentor reticulatus (70 females, 30 males) and Haemaphysalis concinna (12 nymphs, 8 females, 2 males) were negative for spirochetes. The overall prevalence rate of borreliae in I. ricinus from the floodplain forest is slightly higher than the mean European data (i.e., 14% for nymphs, 21% for adults). The difference in infection rate between nymphal and adult ticks was significant, including the proportion of heavily infected (with > 100 borreliae) nymphs (2.1%) vs. adults (7.6%). Prevalence of borreliae in I. ricinus showed a significant decrease during autumn in this ecosystem. Three strains of spirochetes, all of the Borrelia afzelii genomic group, were isolated from female I. ricinus. Moreover, Trypanosoma/Crithidia sp. protozoa and Dipetalonema rugosicauda nematodes were detected in 0.4% and 1.0%, respectively, of all I. ricinus.
Hubálek
Zdenek
Z
Medical Zoology Laboratory, Institute of Vertebrate Biology, Academy of Sciences, Valtice, Czech Republic. zhubalek@brno.cas.cz
Stünzner
Doris
D
Halouzka
Jirí
J
Sixl
Wolfdieter
W
Wendelin
Ilse
I
Juricová
Zina
Z
Sanogo
Yibairi Osée
YO
D000818:Animals; D001317:Austria; D001898:Borrelia / Q000235:genetics / Q000302:isolation & purification*; D025065:Borrelia burgdorferi / Q000235:genetics / Q000302:isolation & purification*; D018153:Czech Republic; D017753:Ecosystem; D005260:Female; D005798:Genes, Bacterial; D018884:Ixodes / Q000382:microbiology* / Q000502:physiology; D008193:Lyme Disease / Q000635:transmission*; D008297:Male; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D014197:Trees