Renata Welc-Falęciak

Babesia canis and other tick-borne infections in dogs in Central Poland.

Vector-borne infections constitute increasing health problem in dogs worldwide, including sled dogs, dramatically decreasing the fitness of working dogs and even leading to death. In the period 2006-2008 eighty-two blood samples were collected from eight sled dog kennels in Central Poland. The prevalence of four vector-borne infections (Babesia canis, Bartonella sp., Anaplasma/Ehrlichia and Borrelia burgdorferi) was estimated in 82 sled dogs using PCR and nested PCR for diagnosis and the same methods were used to identify the vector-borne pathogens in 26 dogs presenting at veterinary clinics with symptoms of vector-borne diseases. None of four studied vector-borne pathogens was detected in samples originating from veterinary clinics. Among the remaining 82 dogs B. canis infections were confirmed in three dogs undergoing treatment for babesiosis. The DNA of tick-borne pathogens was also found among 22 (27.8%) of the 79 apparently healthy dogs, including 20 cases of B. canis infection (25.3%), one case of B. burgdorferi s.l. infection and one case of Anaplasma phagocytophilum infection. No evidence of Bartonella spp. and Ehrlichia canis infections were found in this set of samples. Sequencing of a Babesia fragment of 18S rDNA amplified from acute (n=5) and asymptomatic (n=5) cases revealed that all isolates were identical to the Babesia canis canis sequence, originally isolated from Dermacentor reticulatus ticks in Poland. A range of factors was shown to affect the distribution of babesiosis in sled dogs. The data are also discussed in respect to the health risk factors generated by asymptomatic B. canis infections and the efficiency of chemoprophylaxis measures taken by sled dog owners.

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.

Bartonella spp. Infection in Rodents from Different Habitats in the Mazury Lake District, Northeast Poland

Four rodent species (Clethrionomys glareolus, Apodemus flavicollis, Microtus arvalis, M. oeconomus) were captured in the period 2004-2006 in the Mazury Lake District, Northeast Poland, to determine the prevalence and genetic diversity of Bartonella species. The presence of bartonellae was assessed using polymerase chain reaction (PCR) with primers CS140f and BhCS1137n, amplifying a fragment of the gltA gene. Bartonella DNA was detected in 313 (30.6%) of 1024 rodents sampled: in 181 C. glareolus, 68 A. flavicollis, 50 M. arvalis, and 14 M. oeconomus, representing prevalence of 31.0%, 42.2%, 32.9%, and 11.1%, respectively. Comparison of the Bartonella gltA gene sequences from 38 isolates revealed six phylogenetic subgroups, out of 15 unique gltA sequences, and therein from one to five genotypic variants with homology of 88.6-99.1%. Six of 13 (46.2%) isolates from C. glareolus were identical to B. grahamii, species associated with human illness. These results have important public health implication, notably in relation to the risk of infection in humans following exposure to rodent bartonellae.

Asymptomatic “Candidatus Neoehrlichia mikurensis” Infections in Immunocompetent Humans

ABSTRACT In Europe, human infections with “Candidatus Neoehrlichia mikurensis” have mainly been restricted to immunocompromised patients. We report here the first cases of asymptomatic “Ca. Neoehrlichia mikurensis” infection in immunocompetent humans (5/316 [1.6%] were infected). Due to the potential threats of infections with “Ca. Neoehrlichia mikurensis” in healthy persons to the safety of the blood supply, further study of this phenomenon is required.

Co-infection and genetic diversity of tick-borne pathogens in roe deer from Poland.

Wild species are essential hosts for maintaining Ixodes ticks and the tick-borne diseases. The aim of our study was to estimate the prevalence, the rate of co-infection with Babesia, Bartonella, and Anaplasma phagocytophilum, and the molecular diversity of tick-borne pathogens in roe deer in Poland. Almost half of the tested samples provided evidence of infection with at least 1 species. A. phagocytophilum (37.3%) was the most common and Bartonella (13.4%) the rarest infection. A total of 18.3% of all positive samples from roe deer were infected with at least 2 pathogens, and one-third of those were co-infected with A. phagocytophilum, Bartonella, and Babesia species. On the basis of multilocus molecular studies we conclude that: (1) Two different genetic variants of A. phagocytophilum, zoonotic and nonzoonotic, are widely distributed in Polish roe deer population; (2) the roe deer is the host for zoonotic Babesia (Bab. venatorum, Bab. divergens), closely related or identical with strains/species found in humans; (3) our Bab. capreoli and Bab. divergens isolates differed from reported genotypes at 2 conserved base positions, i.e., positions 631 and 663; and (4) this is the first description of Bart. schoenbuchensis infections in roe deer in Poland. We present 1 of the first complex epidemiological studies on the prevalence of Babesia, Bartonella, and A. phagocytophilum in naturally infected populations of roe deer. These game animals clearly have an important role as reservoir hosts of tick-borne pathogens, but the pathogenicity and zoonotic potential of the parasite genotypes hosted by roe deer requires further detailed investigation.

Borrelia miyamotoi: A human tick-borne relapsing fever spirochete in Europe and its potential impact on public health

Borrelia miyamotoi is a tick-borne bacterium which has only recently been identified in Europe as a human pathogen causing relapsing fever and little is known about its local impact on human health. There are three types of B. miyamotoi: Asian (Siberian), European, and American. B. miyamotoi is transmitted by the same Ixodes ricinus-persulcatus species complex, which also transmits B. burgdorferi s.l., the Lyme borreliosis group. Both Borrelia groups are mostly maintained in natural rodent populations. The aim of this review is to summarize the available literature on B. miyamotoi, with the focus of attention falling on Europe, as well as to describe its presence in ticks, reservoir hosts, and humans and discuss its potential impact on public health.

First report of two asymptomatic cases of human infection with Babesia microti (Franca, 1910) in Poland

Human infection by Babesia microti has been recognized as an emerging zoonosis with important public health implications worldwide. In Europe the reported cases of human babesiosis have been attributed mostly to B. divergens infection, with only sporadic cases of the disease caused by B. microti or B. venatorum. This study, based on molecular methods (PCR, R-T PCR, DNA sequencing and phylogenetic analysis), reveals for the first time in Poland, asymptomatic infection with . microti in immunocompetent healthy individuals working in forest ecosystems. Of the 58 professional foresters examined, two (3.4%) were identified as B. microti-positive by specific PCR. The results of this study also provide strong evidence that in eastern Poland, where tick-borne diseases (TBDs) are endemic, there is a potential risk of acquiring human babesiosis due to zoonotic B. microti parasites commonly found in rodents and I. ricinus ticks. The potential public health importance of this finding is discussed.

The first evidence for vertical transmission of Babesia canis in a litter of Central Asian Shepherd dogs

INTRODUCTION AND OBJECTIVE Tick-borne infections constitute an increasing health problem in dogs and may lead to death, especially in young or elderly individuals. Canine babesiosis constitutes a serious health problem in dogs worldwide. The aim of the study was to verify the probability of vertical transmission of Babesia canis between the bitch and the pups. MATERIALS AND METHODS In Autumn 2011, cases of babesiosis were diagnosed in a litter of 6-week-old puppies of a Central Asian Shepherd dog. Immediately following the first case of infection, blood samples were collected from all the pups in the litter (n=10) and from the female. Detection of Babesia infection was performed by molecular and microscopical techniques. RESULTS The presence of B. canis DNA was detected using PCR in three pups, presenting at the time or 24-48 hours later with babesiosis symptoms, and in their asymptomatic mother. The isolates derived from the pups and the female - 520 bp 18S rRNA gene fragment - were compared and analyzed. All isolates from the pups and their mother were identical and showed 100% homology with B. canis group B (EU622793), supporting the same source of infection. Additionally, the USG of the peritoneal cavity was performed in the female, presenting evidence for splenomegaly. CONCLUSIONS On the basis of (1) the same timing of three pup cases; (2) the identical B. canis sequences derived from all positive dogs; (3) evident splenomegaly in the asymptomatic female, this provides the first evidence of the vertical transmission of this piroplasm in dogs.

Genotyping of Cryptosporidium isolates from human clinical cases in Poland

Cryptosporidium spp. infection is usually self-limited in immunocompetent hosts but can be severe and life threatening in children and in immunocompromised individuals including those with primary or acquired immunodeficiencies. One hundred and three faecal samples were collected from 35 hospitalised patients with different symptoms and tested for the presence of the parasite. Cryptosporidium oocysts were found in four of 35 patients (11.4%) using Ziehl–Neelsen staining of faecal smears and immunofluorescence assay, whereas 12 (34.3%) samples tested positive by nested polymerase chain reaction assay. Cryptosporidium DNA was detected in one bile sample but not in a liver tissue biopsy sample collected from a patient who suffered from sclerosing cholangitis. Sequence analysis of oocyst wall protein and beta-tubulin gene fragments revealed three different parasite species (Cryptosporidium hominis, Cryptosporidium meleagridis and Cryptosporidium parvum) in children with primary immunodeficiencies, whereas only C. parvum was found in immunocompetent individuals and in those with secondary immunodeficiencies. This study has revealed a high prevalence of Cryptosporidium infection in hospitalised patients in Poland and confirmed that molecular techniques enable a more sensitive detection of the parasite.

The first cases of Bartonella bovis infection in cattle from Central Europe

Bartonella bovis was recently identified as a cause of bovine endocarditis, although Bartonella infections in natural hosts are usually asymptomatic. The disease is often misdiagnosed and is only discovered during the slaughtering process. In Europe B. bovis infections in cattle were reported only in France and Italy, nothing is known about the occurrence of B. bovis in cattle for the northern and eastern parts of Europe. The aim of our study was to search for Bartonella DNA in cattle in Central Europe (Poland) using three different loci (rpoB, ITS 16-23S rRNA, gltA). Our study resulted in the first detection of the asymptomatic B. bovis infection in 6.8% (12/177) of cattle in Central Europe. The potential role of B. bovis as a zoonotic agent for domestic animals and human diseases creates the need for further studies of these bacteria in natural and accidental hosts.