Neglected tick-borne pathogens in the Czech Republic, 2011-2014.

In this study, we screened a total of 2473 questing (years 2011-2014) and 199 engorged (years 2013 and 2014) Ixodes ricinus ticks for the presence of Rickettsia spp., "Candidatus Neoehrlichia mikurensis", Anaplasma phagocytophilum, and Babesia spp. Host-seeking ticks were collected at three study sites corresponding to natural woodland, urban park and pastureland ecosystem, and analyzed using molecular techniques. All pathogens tested were present at all study sites. The prevalence rates for Rickettsia spp., 'Candidatus Neoehrlichia mikurensis', Anaplasma phagocytophilum, and Babesia spp. ranged from 2.6% to 9.2%, 0.8% to 11.6%, 0% to 12.1%, and 0% to 5.2%, respectively. Engorged I. ricinus ticks collected from sheep on pastureland in the years 2013 and 2014 yielded prevalence rates 7.4% and 6.3%, respectively, for Rickettsia spp., 38.5% and 14.1% for 'Candidatus N. mikurensis', 18.5% and 12.5% for A. phagocytophilum, and 4.4% and 0.0% for Babesia spp. Monitoring of neglected tick-borne pathogens within the scope of epidemiological surveillance is an important tool for prevention and control of human tick-borne infections.

The common coot as sentinel species for the presence of West Nile and Usutu flaviviruses in Central Europe.

We examined 146 common coots (Fulica atra) on fishponds in central Moravia, Czech Republic, for antibodies to West Nile (WNV) and Usutu (USUV) flaviviruses. Eighteen birds reacted in the plaque-reduction neutralization test against WNV; these WNV seropositive samples were then titrated in parallel against USUV and tick-borne encephalitis virus (TBEV) to exclude flavivirus cross-reactivity. Two birds (1.4% overall) had the highest titers against WNV while 9 birds (6.2% overall) were seropositive for USUV, and in 7 birds the infecting flavivirus could not be differentiated with certainty. Our results indicate that both WNV and USUV infections occur in common coots; these birds might serve as a 'sentinel' species indicating the presence of these viruses at fishpond and wetland habitats in Central Europe.

Zoonotic Dirofilaria repens (Nematoda: Filarioidea) in Aedes vexans mosquitoes, Czech Republic.

The surveillance of vectors for arthropod-borne pathogens is nowadays an important tool in surveillance programmes throughout Europe. Whereas many studies have been performed to screen arthropods for viruses or bacterial pathogens, only limited information is available concerning the geographical distribution and vector range of pathogenic filariae in Central Europe. To consider the prevalence of filarial parasites in mosquito vectors, we performed a molecular survey of mosquitoes for filarial DNA. Mosquito collection was conducted at six study sites in the South Moravian region (Czech Republic) close to the borders with Slovakia and Austria from 2009 to 2011. Molecular screening of mosquitoes was conducted using conventional PCR with primers designed to amplify the mitochondrial cytochromoxidase subunit I gene as well as the partial 5.8S ribosomal RNA gene. A total of 13,222 mosquitoes belonging to six species were captured and distributed into 237 pools with different numbers of individuals. Overall, four pools were positive for Dirofilaria repens (a minimum infection rate 0.03%) at two study sites (both natural and urban). Another filarial parasite detected during a study into Aedes vexans mosquitoes revealed the closest homology to Setaria spp. We detected specific D. repens DNA in Ae. vexans mosquitoes for the first time in the Czech Republic and confirmed the circulation of Dirofilaria spp. in a natural focus of infection providing an epidemiological link between autochthonous canine cases and mosquito vectors in the area studied.

Human pathogenic borreliae in Ixodes ricinus ticks in natural and urban ecosystem (Czech Republic).

A total of 1279 field-collected Ixodes ricinus ticks were screened for Borrelia burgdorferi sensu lato (s.l.) in a natural and an urban ecosystem of Ostrava city (Czech Republic) by using molecular methods. Minimal prevalence rate for Borrelia burgdorferi s.l. in ticks for the urban park Belský les was found to be 13.8% (17.6% in males, 17.8% in females and 11.7% in nymphs), similarly for the natural site Proskovice was minimal prevalence 15% (12.5% in males, 20% in females and 14.9% in nymphs). Six proven human pathogenic genomic species have been recorded in the study: B. afzelii, B. garinii, B. burgdorferi s.s., B. valaisiana, B. lusitaniae, and B. spielmanii. Emerging B. spielmanii was detected for the first time in Ixodes ricinus ticks in the region. Our results highlight the need for surveillance of zoonotic tick-borne pathogens even in urban areas.