Grzegorz Karbowiak

Rickettsiaceae and Anaplasmataceae infections in Ixodes ricinus ticks from urban and natural forested areas of Poland

BackgroundIxodes ricinus is a major vector for a range of microbial pathogens and the most prevalent and widely distributed tick species on the European continent, occurring in both natural and urban habitats. Nevertheless, little is known about the relative density of ticks in these two ecologically distinct habitats and the diversity of tick-borne pathogens that they carry.MethodsWe compared densities of questing I. ricinus nymphs and adults in urban and natural habitats in Central and Northeastern Poland, assessed the prevalence and rate of co-infection with A. phagocytophilum, Rickettsia, Ehrlichia and ‘Ca. Neoehrlichia spp.’ in ticks, and compared the diversity of tick-borne pathogens using molecular assays (PCR).ResultsOf the 1325 adults and nymphs, 6.2% were infected with at least one pathogen, with 4.4%, 1.7% and less than 0.5% being positive for the DNA of Rickettsia spp., A. phagocytophilum, Ehrlichia spp. and Ca. N. mikurensis, respectively. Although tick abundance was higher in natural habitats, the prevalence of the majority of pathogens was higher in urban forested areas.ConclusionWe conclude that: (i) zoonotic genetic variants of A. phagocytophilum are widely distributed in the Polish tick population, (ii) although the diversity of tick borne pathogens was higher in natural habitats, zoonotic species/strains were detected only in urban forests, (iii) and we provide the first description of Ca. N. mikurensis infections in ticks in Poland.

Apicomplexan parasites of red foxes (Vulpes vulpes) in northeastern Poland

Molecular detection of apicomplexan parasites in splenic samples of red foxes collected from northeastern Poland was conducted by PCR amplification of a fragment of the 18S rRNA spanning the V4 gene region of Apicomplexa. Positive PCR products were further analysed by restriction fragment length polymorphism (RFLP) and sequencing to identify species. One hundred and eleven red foxes (Vulpes vulpes) were acquired from 15 localities in the Mazovian Province and 27 foxes were acquired from the Mazurian Lakeland. Apicomplexan 18S rDNA was detected in 15.9% of 138 fox spleens examined. Three apicomplexan species were identified: Hepatozoon canis was detected in 11.6% of the spleen samples, Toxoplasma gondii was detected in 3.6% of the spleen samples and a Babesia sp. was sequenced from 1 sample (0.7%). This data represent the first record of H. canis, T. gondii and a B. sp. from naturally infected red foxes in Poland. Infected foxes may act as sylvatic reservoirs of these apicomplexan parasites as well as serving as a source of infection for arthropod definitive hosts and vectors.

Natural infections of small mammals with blood parasites on the borderland of boreal and temperate forest zones

Blood parasites of small mammals living in Białowieża Forest (eastern Poland) were investigated between 1996 and 2002. The following haemoparasite species were found:Trypanosoma (Herpetosoma) evotomys in bank voleClethrionomys glareolus; T. (H.) microti in root voleMicrotus oeconomus; Babesia microti in root vole;Hepatozoon erhardovae in bank vole andHepatozoon sp. in root vole. Some non-identifiedBartonella species were found in bank vole, root vole, field voleMicrotus agrestis, yellow-necked mouseApodemus flavicollis, common shrewSorex araneus, Eurasian water shrewNeomys fodiens, and Mediterranean water shrewN. anomalus. The prevalence and diversity of blood parasites were lower in shrews than small rodents. Totally, 52.0% of bank voles, 50.0% of root voles, 32.5% of common shrews, and 41.2% of Eurasian water shrews were infected with any of the blood parasites. Mixed infections were seldom observed in bank vole (17.3% of investigated individuals) and root vole (14.7%). No animals were infected with three or four parasites simultaneously. Infection of Białowieża small mammals with haemoparasites seemed to be similar to those described in other temperate forest regions rather than boreal ones. Infection rates of rodent species seem to be higher in their typical habitats: for bank vole it was the highest in mixed forest, whereas for root vole in sedge swamp. The results suggest that Arvicolidae play a greater role than Muridae or Soricidae in maintenance ofBabesia andHepatozoon foci in natural environments of central Europe.

The parasitic fauna of the European bison (Bison bonasus) (Linnaeus, 1758) and their impact on the conservation. Part 1 The summarising list of parasites noted

During the current century, 88 species of parasites have been recorded in Bison bonasus. These are 22 species of protozoa (Trypanosoma wrublewskii, T. theileri, Giardia sp., Sarcocystis cruzi, S. hirsuta, S. hominis, S. fusiformis, Neospora caninum, Toxoplasma gondii, Cryptosporidium sp., Eimeria cylindrica, E. subspherica, E. bovis, E. zuernii, E. canadensis, E. ellipsoidalis, E. alabamensis, E. bukidnonensis, E. auburnensis, E. pellita, E. brasiliensis, Babesia divergens), 4 trematodes species (Dicrocoelium dendriticum, Fasciola hepatica, Parafasciolopsis fasciolaemorpha, Paramphistomum cervi), 4 cestodes species (Taenia hydatigena larvae, Moniezia benedeni, M. expansa, Moniezia sp.), 43 nematodes species (Bunostomum trigonocephalum, B. phlebotomum, Chabertia ovina, Oesophagostomum radiatum, O. venulosum, Dictyocaulus filaria, D.viviparus, Nematodirella alcidis, Nematodirus europaeus, N. helvetianus, N. roscidus, N. filicollis, N. spathiger, Cooperia oncophora, C. pectinata, C. punctata, C. surnabada, Haemonchus contortus, Mazamastrongylus dagestanicus, Ostertagia lyrata, O. ostertagi, O. antipini, O. leptospicularis, O. kolchida, O. circumcincta, O. trifurcata, Spiculopteragia boehmi, S. mathevossiani, S. asymmetrica, Trichostrongylus axei, T. askivali, T. capricola, T. vitrinus, Ashworthius sidemi, Onchocerca lienalis, O. gutturosa, Setaria labiatopapillosa, Gongylonema pulchrum, Thelazia gulosa, T. skrjabini, T. rhodesi, Aonchotheca bilobata, Trichuris ovis), 7 mites (Demodex bisonianus, D. bovis, Demodex sp., Chorioptes bovis, Psoroptes equi, P. ovis, Sarcoptes scabiei), 4 Ixodidae ticks (Ixodes ricinus, I. persulcatus, I. hexagonus, Dermacentor reticulatus), 1 Mallophaga species (Bisonicola sedecimdecembrii), 1 Anoplura (Haematopinus eurysternus), and 2 Hippoboscidae flies (Lipoptena cervi, Melophagus ovinus). There are few monoxenous parasites, many typical for cattle and many newly acquired from Cervidae.

The parasitic fauna of the European bison (Bison bonasus) (Linnaeus, 1758) and their impact on the conservation. Part 2 The structure and changes over time

During the last century the recorded parasite fauna of Bison bonasus includes 88 species. These are 22 species of protozoa, 4 trematode species, 4 cestode species, 43 nematode species, 7 mites, 4 Ixodidae ticks, 1 Mallophaga species, 1 Anoplura, and 2 Hippoboscidae flies. There are few monoxenous parasites, the majority of parasites are typical for other Bovidae and Cervidae species and many are newly acquired from Cervidae. This is an evident increased trend in the parasite species richness, in both the prevalence and intensity of infections, which is associated with the bison population size, host status (captive breeding or free-ranging) and the possibility of contact with other ruminant species. In light of the changes to parasite species richness during the last decades, special emphasis shall be given to new parasite species reported in European bison, their pathogenicity and potential implications for conservation.

New records of spotted fever group rickettsiae in Baltic region

Tick-borne rickettsiae are considered to be emerging, but there is still a lack of data on the occurrence and prevalence of the spotted fever group rickettsiae across Europe, especially in the Baltic countries. The aim of the present study was to investigate the presence of Rickettsia spp. in Dermacentor reticulatus and Ixodes ricinus ticks, as well as to determine their prevalence in various regions of Lithuania and Latvia. The prevalence of Rickettsia spp. in geographically distinct populations of D. reticulatus on transect Baltic-Adriatic regions was compared. The molecular analyses of 1859 D. reticulatus and 361 I. ricinus from 48 localities in Lithuania and Latvia revealed the presence of Rickettsia raoultii in D. reticulatus and Rickettsia helvetica in I. ricinus. The prevalence of pathogens in D. reticulatus (4.9%) and I. ricinus (17%) ranged in different locations from 0% to 36.9% and 0%-31.3%, respectively. Higher overall infection rates were detected in D. reticulatus collected in Poland (15.8%) and Slovakia (11.4%), with the prevalence range in different locations from 0% to 59.6%. Our study is the first demonstration of the presence of R. raoultii in D. reticulatus ticks in the Baltic countries and R. helvetica in questing I. ricinus ticks in Lithuania.

Coexistence of Borrelia burgdorferi s.l. genospecies within Ixodes ricinus ticks from central and eastern Poland

The purpose of the study was to assess the prevalence and coinfection rates of Borrelia burgdorferi sensu lato genotypes in Ixodes ricinus (L.) ticks sampled from diverse localities in central and eastern regions of Poland. In years 2009–2011, questing nymphs and adults of I. ricinus were collected using a flagging method at 18 localities representing distinct ecosystem types: urban green areas, suburban forests and rural woodlands. Molecular detection of B. burgdorferi s.l. genospecies was based on amplification of a fla gene using nested PCR technique, subsequent PCR-RFLP analysis and bidirectional sequencing. It was revealed that 45 samples (2.1%) harboured two different B. burgdorferi s.l. genospecies, whereas triple infections with various spirochetes was found in 11 (0.5%) individuals. Generally, the highest average coinfection rates were evidenced in arachnids gathered at rural woodlands, intermediate at suburban forests, while the lowest were recorded at urban green areas. Overall, single spirochete infections were noted in 16.3% (n = 352/2,153) ticks. Importantly, it is the first report evidencing the occurrence of Borrelia miyamotoi (0.3%, n = 7/2153) in I. ricinus populations within central Poland. Circumstantial variability of B. burgdorferi s.l. genospecies in the common tick individuals sampled at various habitat types in central and eastern Poland was displayed. The coexistence of two or three different spirochete genospecies in single adult ticks, as well as the presence of B. miyamotoi were demonstrated. Therefore, further studies uncovering the co-circulation of the tested bacteria and other human pathogens in I. ricinus ticks are required.

The transstadial persistence of tick-borne encephalitis virus in Dermacentor reticulatus ticks in natural conditions

There are a number of reports regarding natural infection of Dermacentor reticulatus ticks with TBE virus; however, the transmission mode of TBE virus in this tick population has not been investigated. This study was conducted in Białowieża Primeval Forest, east Poland. Forty fully engorged nymphs of D. reticulatus were sampled from root voles (Microtus oeconomus). Ticks were kept until molting. All ticks were screened for the presence of TBE virus by nested RT-PCR. Three adult ticks were positive for infection with TBE virus. The present study for the first time demonstrates the possibility of transstadial mode of TBEV transmission in D. reticulatus ticks.

Molecular surveillance of Theileria equi and Anaplasma phagocytophilum infections in horses from Ukraine, Poland and Slovakia

A survey was undertaken to assess the prevalence of Theileria equi and Anaplasma phagocytophilum in some regions of Ukraine, Poland and Slovakia. Using a specific PCR assays, blood samples from 215 horses were tested. The prevalence of T. equi and A. phagocytophilum infection was 13.95% and 1.4%, respectively. BLAST analysis showed the isolates closest to the T. equi 18S rRNA and A. phagocytophilum msp4 gene sequences in GenBank with a similarity of ≥99%. No significant association was found between the T. equi PCR positivity and the age or sex of the horses. There was a significant association between the origin of horses and T. equi-PCR positivity. No significant association was found between the A. phagocytophilum-PCR positivity and the age, sex or origin.

The role of particular tick developmental stages in the circulation of tick-borne pathogens affecting humans in Central Europe. 3. Rickettsiae.

UNLABELLED Ixodes ricinus, Dermacentor reticulatus and D. marginatus ticks are the most important vector for Rickettsia spp. in Central Europe. Ticks sustain rickettsial transmission cycles transovarially and transstadially, it makes enable the rickettsial circulation in the tick population in the absence of vertebrate competent reservoir. Rickettsia helvetica is transmitted by I. ricinus tick; the highest rates of infection are noted in adult females, lower in males and in nymphs. All tick developmental stages apart males are able to infect mammal hosts and humans. The potential animal reservoir could be wild boar, the role of deer is unclear; small rodents maintain the tick population. Rickettsia slovaca is transmitted by D. marginatus and D. reticulatus ticks. The available data suggest the role of wild boars and Apodemus mice as animal reservoir. The ticks able to infect human are adults D. marginatus. Rickettsia raoultii is transmitted by D. marginatus and D. reticulatus. The infections of mammals are not recorded. As in Rickettsia slovaca, human can be infected by adults D. marginatus. Rickettsia monacensis is transmitted in Central Europe by I. ricinus tick (apart males), although there is a documented infection of Dermacentor ticks. The differences in the infection rates of ticks larvae, nymphs and adults suggest the limited role of transovarial transmission, and the participation of mammals in the zoonotic cycle, being the source of infection for larvae and nymphs. KEY WORDS SFG, Rickettsia slovaca, Rickettsia helvetica, Rickettsia raoultii, Rickettsia monacensis, ticks.