Nejvíce citovaný článek - PubMed ID 9521004
Prevalence rates of Borrelia burgdorferi sensu lato in host-seeking Ixodes ricinus ticks in Europe
Lyme borreliosis is the most common zoonotic disease transmitted by ticks in Europe and North America. Despite having multiple tick vectors, the causative agent, Borrelia burgdorferisensu lato, is vectored mainly by Ixodes ricinus in Europe. In the present study, we aimed to review and summarize the existing data published from 2010 to 2016 concerning the prevalence of B. burgdorferi sensu lato spirochetes in questing I. ricinus ticks. The primary focus was to evaluate the infection rate of these bacteria in ticks, accounting for tick stage, adult tick gender, region, and detection method, as well as to investigate any changes in prevalence over time. The data obtained were compared to the findings of a previous metastudy. The literature search identified data from 23 countries, with 115,028 ticks, in total, inspected for infection with B. burgdorferi sensu lato We showed that the infection rate was significantly higher in adults than in nymphs and in females than in males. We found significant differences between European regions, with the highest infection rates in Central Europe. The most common genospecies were B. afzelii and B. garinii, despite a negative correlation of their prevalence rates. No statistically significant differences were found among the prevalence rates determined by conventional PCR, nested PCR, and real-time PCR.IMPORTANCEBorrelia burgdorferisensu lato is a pathogenic bacterium whose clinical manifestations are associated with Lyme borreliosis. This vector-borne disease is a major public health concern in Europe and North America and may lead to severe arthritic, cardiovascular, and neurological complications if left untreated. Although pathogen prevalence is considered an important predictor of infection risk, solitary isolated data have only limited value. Here we provide summarized information about the prevalence of B. burgdorferi sensu lato spirochetes among host-seeking Ixodes ricinus ticks, the principal tick vector of borreliae in Europe. We compare the new results with previously published data in order to evaluate any changing trends in tick infection.
- Klíčová slova
- Borrelia burgdorferi sensu lato, Ixodes ricinus, Lyme borreliosis, Lyme disease, genospecies, meta-analysis, tick,
- MeSH
- arachnida jako vektory mikrobiologie MeSH
- Borrelia burgdorferi klasifikace genetika izolace a purifikace MeSH
- klíště mikrobiologie MeSH
- lidé MeSH
- lymeská nemoc mikrobiologie přenos MeSH
- nymfa mikrobiologie MeSH
- prevalence MeSH
- zoonózy mikrobiologie přenos MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- metaanalýza MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Evropa MeSH
Tick-borne diseases represent major public and animal health issues worldwide. Ixodes ricinus, primarily associated with deciduous and mixed forests, is the principal vector of causative agents of viral, bacterial, and protozoan zoonotic diseases in Europe. Recently, abundant tick populations have been observed in European urban green areas, which are of public health relevance due to the exposure of humans and domesticated animals to potentially infected ticks. In urban habitats, small and medium-sized mammals, birds, companion animals (dogs and cats), and larger mammals (roe deer and wild boar) play a role in maintenance of tick populations and as reservoirs of tick-borne pathogens. Presence of ticks infected with tick-borne encephalitis virus and high prevalence of ticks infected with Borrelia burgdorferi s.l., causing Lyme borreliosis, have been reported from urbanized areas in Europe. Emerging pathogens, including bacteria of the order Rickettsiales (Anaplasma phagocytophilum, "Candidatus Neoehrlichia mikurensis," Rickettsia helvetica, and R. monacensis), Borrelia miyamotoi, and protozoans (Babesia divergens, B. venatorum, and B. microti) have also been detected in urban tick populations. Understanding the ecology of ticks and their associations with hosts in a European urbanized environment is crucial to quantify parameters necessary for risk pre-assessment and identification of public health strategies for control and prevention of tick-borne diseases.
- Klíčová slova
- Europe, Ixodes ricinus, tick-borne pathogens, ticks, urban habitats,
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
BACKGROUND: During the last decades, population densities of Ixodes ricinus and prevalences of Borrelia burgdorferi s.l. have increased in different regions in Europe. In the present study, we determined tick abundance and the prevalence of different Borrelia genospecies in ticks from three sites in the Siebengebirge, Germany, which were already examined in the years 1987, 1989, 2001 and 2003. Data from all investigations were compared. METHODS: In 2007 and 2008, host-seeking I. ricinus were collected by monthly blanket dragging at three distinct vegetation sites in the Siebengebirge, a nature reserve and a well visited local recreation area near Bonn, Germany. In both years, 702 ticks were tested for B. burgdorferi s.l. DNA by nested PCR, and 249 tick samples positive for Borrelia were further genotyped by reverse line blotting. RESULTS: A total of 1046 and 1591 I. ricinus were collected in 2007 and 2008, respectively. In comparison to previous studies at these sites, the densities at all sites increased from 1987/89 and/or from 2003 until 2008. Tick densities and Borrelia prevalences in 2007 and 2008, respectively, were not correlated for all sites and both years. Overall, Borrelia prevalence of all ticks decreased significantly from 2007 (19.5%) to 2008 (16.5%), thus reaching the same level as in 2001 two times higher than in 1987/89 (7.6%). Since 2001, single infections with a Borrelia genospecies predominated in all collections, but the number of multiple infections increased, and in 2007, for the first time, triple Borrelia infections occurred. Prevalences of Borrelia genospecies differed considerably between the three sites, but B. garinii or B. afzelii were always the most dominant genospecies. B. lusitaniae was detected for the first time in the Siebengebirge, also in co-infections with B. garinii or B. valaisiana. CONCLUSIONS: Over the last two centuries tick densities have changed in the Siebengebirge at sites that remained unchanged by human activity since they belong to a nature reserve. Abiotic and biotic conditions most likely favored the host-seeking activity of I. ricinus and the increase of multiple Borrelia infections in ticks. These changes have led to a potential higher risk of humans and animals to be infected with Lyme borreliosis.
- MeSH
- Borrelia burgdorferi komplex klasifikace genetika izolace a purifikace MeSH
- časové faktory MeSH
- DNA bakterií genetika MeSH
- hustota populace MeSH
- klíště růst a vývoj mikrobiologie MeSH
- polymerázová řetězová reakce MeSH
- prevalence MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Německo MeSH
- Názvy látek
- DNA bakterií MeSH
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.
- MeSH
- bakteriální geny MeSH
- Borrelia burgdorferi genetika izolace a purifikace MeSH
- Borrelia genetika izolace a purifikace MeSH
- ekosystém MeSH
- klíště mikrobiologie fyziologie MeSH
- lymeská nemoc přenos MeSH
- polymerázová řetězová reakce MeSH
- polymorfismus délky restrikčních fragmentů MeSH
- stromy MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- srovnávací studie MeSH
- Geografické názvy
- Česká republika MeSH
- Rakousko MeSH
In Europe the Borrelia burgdorferi sensu lato complex is represented by five distinct genospecies: Borrelia burgdorferi sensu stricto, Borrelia afzelii, Borrelia garinii, Borrelia valaisiana, and Borrelia lusitaniae. These taxonomic entities are known to differ in their specific associations with vertebrate hosts and to provoke distinct clinical manifestations in human patients. However, exceptions to these rules have often been observed, indicating that strains belonging to a single genospecies may be more heterogeneous than expected. It is, therefore, important to develop alternative identification tools which are able to distinguish Borrelia strains not only at the specific level but also at the intraspecific level. DNA from a sample of 370 Ixodes ricinus ticks collected in the Czech Republic was analyzed by PCR for the presence of a approximately 230-bp fragment of the rrfA-rrlB intergenic spacer of Borrelia spp. A total of 20.5% of the ticks were found to be positive. The infecting genospecies were identified by analyzing the amplified products by the restriction fragment length polymorphism (RFLP) method with restriction enzyme MseI and by single-strand conformation polymorphism (SSCP) analysis. The two methods were compared, and PCR-SSCP analysis appeared to be a valuable tool for rapid identification of spirochetes at the intraspecific level, particularly when large samples are examined. Furthermore, by using PCR-SSCP analysis we identified a previously unknown Borrelia genotype, genotype I-77, which would have gone unnoticed if RFLP analysis alone had been used.
- MeSH
- Borrelia burgdorferi komplex klasifikace genetika MeSH
- DNA bakterií genetika izolace a purifikace MeSH
- fylogeneze MeSH
- genetická variace * MeSH
- genotyp MeSH
- klíště mikrobiologie MeSH
- lidé MeSH
- mezerníky ribozomální DNA genetika MeSH
- molekulární sekvence - údaje MeSH
- polymerázová řetězová reakce metody MeSH
- polymorfismus délky restrikčních fragmentů MeSH
- polymorfismus konformace jednovláknové DNA * MeSH
- sekvenční analýza DNA MeSH
- techniky typizace bakterií MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- hodnotící studie MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Česká republika MeSH
- Názvy látek
- DNA bakterií MeSH
- mezerníky ribozomální DNA MeSH