Q112445587
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Cíl práce: Cílem tříletého sledování (2011–2013) výskytu klíštěte obecného Ixodes ricinus bylo ověřit v oblastech se zvýšenou incidencí klíšťové encefalitidy (zjištěnou v předchozí dekádě 2001–2010) jednak stavy místních populací tohoto přenašeče, jednak jeho infikovanost virem klíšťové encefalitidy. Takto komplexně zaměřený a dlouhodobý výzkum založený na předchozích epidemiologických zjištěních nebyl dosud v Evropě realizován. Materiál a metodika:Ve vybraných lokalitách krajů Ústeckého, Olomouckého, Jihočeského a kraje Vysočina byly stanoveny fixní plochy (každá 600 m2) v optimálních místních habitatech I. ricinus, na nichž byl prováděn každoroční kontrolní sběr v jaroletní a podzimní sezoně aktivity klíšťat. Celkem bylo shromážděno a laboratorně vyšetřeno 18.721 klíšťat I. ricinus (z toho 1448 samic, 1425 samců a 15.848 nymf). Výsledky a závěry: Výsledky ukazují, že pozorované regionální rozdíly v infikovanosti I. ricinus jsou založeny na stavu místní populace těchto klíšťat ovlivněné charakterem celé lokální biocenózy. Dynamika jejích sezonních změn, podmíněná především klimatickými faktory, určuje meziroční rozdíly infikovanosti I. ricinus, a tak i změny epidemiologické situace nákaz klíšťaty přenášených. Číselný poměr aktivních dospělců a nymf klíšťat vykazuje v různých oblastech značnou variabilitu a mohl by být v budoucnu použit jako jeden z indikátorů charakterizujících místní populace I. ricinus, úroveň zoonotické cirkulace viru klíšťové encefalitidy, a tak i zdravotní riziko dané oblasti. Dále bylo zjištěno, že populace klíšťat dotčená lokálně jednorázově působícími extrémními meteorologickými jevy, se rychle meziročně obnovuje. Ačkoliv je stále pozorováno pronikání I. ricinus a jimi přenášených patogenů do vyšších nadmořských poloh, vysoké riziko lidských nákaz virem klíšťové encefalitidy je ve sledovaných regionech dosud do úrovně 600 m n. m.
Study objective: The aim of the three-year study (2011–2013) was to monitor population density of Ixodes ricinus ticks and its infection rate with the tick-borne encephalitis virus in areas with a high incidence of tick-borne encephalitis as reported in the previous decade 2001–2010. Such a comprehensive and long-term study based on existing epidemiological findings has not previously been conducted in Europe. Material and methods: In the areas of the Ústí nad Labem Region, Olomouc Region, South Bohemian Region, and Highlands Region, 600 m2 plots were selected in the local optimal I. ricinus habitats where tick flagging was performed every year in the spring-summer and autumn seasons of the questing activity. In total, 18,721 I. ricinus ticks (1448 females, 1425 males, and 15,848 nymphs) were collected and investigated. Results and conclusion: The results have shown that the differences in the infection rate of I. ricinus observed between regions are driven by variation in the density of the local I. ricinus populations which is influenced by the characteristics of the whole local biocenosis. The overall prevalence estimate of TBE virus in Ixodes ricinus ticks at the altitudes below 600 m a.s.l. was 0.096 % (95% CI 0.055–0.156) for nymphs, and 0.477 % (95% CI 0.272–0.773) for adults. The dynamics of the seasonal variation in I. ricinus populations, depending primarily on the climatic factors, are behind the interyear differences in the infection rate of ticks and, consequently, in the epidemiological situation of tick-borne encephalitis. The nymph to adult ratio was 5.5 on average but showed great interregional variability (from 10.3 in the Ústí nad Labem Region to 1.8 in the Highlands Region). It might be used in the future as one of the indicators of the composition of the local I. ricinus population and of the level of the circulation of tick-borne pathogens in zoonotic sphere and also for use in the health risk assessment in a given area. Despite the permanent expansion of ticks and tick-borne pathogens in higher altitudes the high risk limit for human infection with tick-borne encephalitis is 600 m a.s.l. in the Czech Republic.
- MeSH
- epidemiologické monitorování MeSH
- hodnocení rizik MeSH
- klíště * virologie MeSH
- klíšťová encefalitida epidemiologie MeSH
- lineární modely MeSH
- nadmořská výška * MeSH
- podnebí MeSH
- roční období MeSH
- viry klíšťové encefalitidy * izolace a purifikace MeSH
- životní prostředí MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- práce podpořená grantem MeSH
- Geografické názvy
- Česká republika MeSH
A study of the vertical distribution of the common tick Ixodes ricinus and tick-borne pathogens – tick-borne encephalitis virus (TBEV) and genospecies of Borrelia burgdorferi s.l. – was performed in the highest part of the Jeseníky mountain area (the Hrubý Jeseník Mts. with the highest summit Praděd, 1,491 m above see level). Altogether 1,253 specimens of all tick stages (607 larvae, 614 nymphs, 8 females and 24 males) were collected at the altitude 990–1,300 m above sea level on 12 collection sites by the flagging method. Altogether 1,207 ticks (8 females, 24 males, 568 nymphs and 607 larvae) were examined for the presence of tick-borne encephalitis virus and B. burgdorferi s.l. None of the samples contained TBEV, 35 samples (6% of adult ticks, 5% of nymphs, 0.7% of larvae) were positive for B. burgdorferi s.l. The most prevalent genospecies were B. afzelii (44%), B. garinii (28%), less frequent were B. burgdorferi sensu stricto (5%), B. valaisiana (3%). The rather large number of ticks (in absolute numbers as well as recounted to the index: average number of nymphs/worker/collection hour) and the presence of all developmental stages clearly demonstrate that there are viable local tick populations in all the sites, and that recorded ticks were not randomly individuals brought into higher altitudes by birds or game animals. The results are compared with the long-term (2002–2007) monitoring of the tick altitudinal distribution in the Krkonoše Mts. and the conditions, which allow ticks to establish local populations up to the timberline in both mountain areas, are discussed. Simultaneously, changes in climatic conditions (especially the air temperature) monitored at 3 meteorological stations in the area of the Jeseníky Mts. were compared with the records from another 8 stations in other mountain areas in the Czech Republic. A very similar statistically significant trend of increasing mean air temperatures during the last three decades is found at all analyzed stations. The trend is most pronounced in the spring and summer months with the highest activity of I. ricinus ticks.
- MeSH
- Borrelia burgdorferi izolace a purifikace MeSH
- financování organizované MeSH
- klíště mikrobiologie virologie MeSH
- nadmořská výška MeSH
- skleníkový efekt MeSH
- surveillance populace MeSH
- viry klíšťové encefalitidy izolace a purifikace MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Geografické názvy
- Česká republika MeSH
Along with the shift of the hard tick Ixodes ricinus to higher altitudes observed in the Czech Republic a corresponding shift of tick-borne infections to higher altitudes has been expected. Therefore, I. ricinus ticks, mainly nymphs, were investigated for the presence of tick-borne viruses, tick-borne encephalitis (TBE), Tribec and Eyach, and the spirochaete Borrelia burgdorferi sensu lato in the Sumava and Krkonose Mountains (Czech Republic). The TBE virus and different genospecies of B. burgdorferi s.l. were detected by RT-PCR and PCR, respectively. TBE virus was detected in ticks at 620 and 720 m above sea level (a.s.l.), B. burgdorferi s.l. was detected in ticks up to 1065 m a.s.l. Four genospecies of B. burgdorferi s.l. were identified, B. afzelii, B. garinii, B. burgdorferi sensu stricto, and B. valaisiana. Some nymphs carried multiple Borrelia infections. The conditions of tick-borne agents' distribution and potential epidemiological consequences are discussed.
- MeSH
- Borrelia burgdorferi komplex izolace a purifikace MeSH
- financování organizované MeSH
- hustota populace MeSH
- klíště mikrobiologie virologie MeSH
- lidé MeSH
- nadmořská výška MeSH
- viry klíšťové encefalitidy izolace a purifikace MeSH
- zeměpis MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Geografické názvy
- Česká republika MeSH
The aim of the study was to monitor present status of the Ixodes ricinus tick vertical distribution in the Krkonoše Mts. (Czech Republic) and evaluate its potential changes. Two methods were used: monitoring of tick presence on dogs in 2001–2002 and direct monitoring of host-seeking ticks by flaggingontwoverticaltransectsreachingfrom620to 1270 m above sea level (a. s. l.) and from 600 to 1020 m in 2002–2003. Moreover ticks were monitored by flaggingatanother13localitiessituatedin800–1299ma.s.l.in2003. Both monitoring methods revealed an obvious shift in altitudinal distribution limit of the tick I. ricinus in the Krkonoše Mts. They both showed that ticks recently penetrate even up to a timberline (approximately 1250 m a. s. l.). The number of recorded host-seeking ticks rapidly decreased with increasing altitude. Whereas the average number of recorded nymphs converted per 60 minutes of flaggingreached15.2–25.7nymphsin700–799ma.s.l.and3.3–23.3in800–899m,itwas4–9.6nymphsin900–999m,1.5–1.7 nymphs in 1000–1099 m and only 0.2 nymph in 1100–1299 m a. s. l. The observed shift of the tick altitudinal distribution limit at the same time results in extension of areas with potential risk of tick-borne diseases.
- MeSH
- klíště MeSH
- kontrola klíšťat MeSH
- monitorování životního prostředí MeSH
- nadmořská výška MeSH
- podnebí MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Geografické názvy
- Česká republika MeSH
- MeSH
- klíště parazitologie MeSH
- klíšťová encefalitida epidemiologie MeSH
- nadmořská výška MeSH
- Geografické názvy
- Česká republika MeSH