Experimental and Natural Infections of Tick-Borne Encephalitis Virus in Dogs.

Dogs are frequently infected with the tick-borne encephalitis virus (TBEV). However, to date, only a few clinically manifest cases of tick-borne encephalitis (TBE) have been reported in dogs. In this study, three-month-old beagle dogs were infected with TBEV through a subcutaneous injection. Body temperature, clinical signs, blood haematology, blood biochemistry, and immune responses were monitored for up to 28 days postinfection (p.i.). No changes in body temperature or clinical signs were observed in the infected dogs. Most haematology and blood biochemistry parameters were unchanged after the infection, except for a slight reduction in blood lymphocyte counts, but they were within the physiological range. Low-titre viraemia was detected in 2/4 infected dogs between days 1 and 3 p.i. All infected dogs developed a robust immune response, in terms of neutralising antibodies. Thus, TBEV infections lead to effective seroconversion in dogs. Next, to assess TBEV exposure in dogs in the TBEV-endemic region of the Czech Republic, we conducted a serosurvey. Virus neutralisation tests revealed TBEV-specific antibodies in 17 of 130 (13.07%) healthy dogs, which confirmed a high, but clinically inappreciable TBEV exposure rate in the endemic area. The seropositivity rate was similar (12.7%; 41 positives out of 323) in a subgroup of dogs with various clinical disorders, and it was 13.4% (23 out of 171) in a subgroup of dogs with signs of acute neurological disease. Two dogs with fatal acute meningoencephalitis showed positive results for TBEV-specific IgM and IgG antibodies. These data extended our understanding of the clinical presentation of TBEV infections.

Seroprevalence of Antibodies against Borrelia burgdorferi s. l. and Leptospira interrogans s. l. in Cats in district of Brno and its environs, the Czech Republic.

OBJECTIVES: The aim of this study is to evaluate the seroprevalence of antibodies of Borrelia burgdorferi sensu lato (Bbsl) and Leptospira interrogans sensu lato (Lisl) and their possible concurrence in domestic cats living in variable conditions in South Moravia in the district of Brno and its environs. Additional objectives were to discover possible differences in seroprevalence between groups of cats living in different living conditions, and to determine the spectrum of Leptospira serogroups in cats in the same places. MATERIAL AND METHODS: A total of 360 blood sera from domestic cats of 3 different sets were collected during the period 2013-2015. All samples were examined using ELISA for the detection of IgM and IgG antibodies against Bbsl, and the microscopic agglutination test (MAT) for the detection of antibodies against 8 serogroups of Lisl. RESULTS: The ELISA method determined 15.8%, 4.8% and 10.3% IgM anti-Borrelia antibodies in the patient group, shelter cats and street cats, respectively. IgG anti-Borrelia antibodies were found in 6.2%, 9.5%, 5.2%, respectively. Antibodies specific for 5 Leptospira serogroups were detected by the use of MAT in 8.8%, 9.5% and 10.3% of cats from the investigated groups. The total positivity of all examined cats for anti-Borrelia antibodies was 18.0% and for anti-Leptospira - 9.2%. CONCLUSIONS: Cats can be infected with both Bbsl and Lisl. The obtained results are exclusive to the city of Brno and its environs, and are comparable to the limited previous studies. There is a need for further studies of clinical signs of both infections and the possible transmission of Leptospira by ticks.

Tick-borne encephalitis in dogs: application of "nested real-time RT-PCR" for intravital virus detection.

Tick-borne encephalitis (TBE) virus is a tick-transmitted virus causing disorders of the nervous system in humans, monkeys, dogs and horses (rarely). At present the detection of TBE infection in dogs is performed by confirmation of seroconversion in paired samples of serum in clinical practice. The intention of the study was the assessment of the possible application of nested real-time RT-PCR for detection of TBE virus in canine blood. The study was carried out in 2011-2012 using samples originating in the Czech Republic, South Moravian region (region with endemic occurrence of TBE). The dogs were randomly selected from the patients visiting the clinic during this time period. Of the total amount of 159 canine blood samples, 20 samples were tested with a PCR-positive result (12.6%). Out of these 20 animals, the neurological clinical symptoms typical of TBE were detected in seven dogs. PCR-positive results were found between March and November. Three dogs were tested with a competitive ELISA-positive result and a "nested real-time RT-PCR"-positive result concurrently. In the group of 159 dogs the value of seroprevalence was found to be 11.3%.

Whole genome sequencing and phylogenetic analysis of feline anelloviruses.

Torque teno felis virus (FcTTV) was detected in the cat population in the Czech Republic. A total of 110 serum samples were tested by a nested PCR technique using specific primers, situated in the highly conserved untranslated region of the virus genome. The frequency of feline TT virus in the Czech Republic was found to be 33.63%. Sequencing of PCR product from several virus strains showed that all of them are closely related and belong to the same virus species. Whole genome sequencing of three strains was performed to compare overall genetic heterogeneity of feline TT viruses. One of these three strains showed more that 10% difference at the nucleotide level. Furthermore we didn't find any correlation between FcTTV infection and sex or health status of examined animals.

Emergence and genetic variability of Anaplasma species in small ruminants and ticks from Central Europe.

Anaplasmoses are common tick-borne zoonotic bacterial diseases of livestock and free-living ungulates from the genus Anaplasma that are recently emerging in Central Europe. The main aim of this study was to analyze the prevalence and genetic variability of Anaplasma phagocytophilum and Anaplasma ovis in small ruminants and questing ticks from six different sites in Slovakia and the Czech Republic using the PCR of the msp4 gene followed by the sequence analysis. At two farms from southeastern Slovakia, 66.1% small ruminants were infected with A. ovis in contrast to one positive animal from both sites in northern Slovakia. It was represented by two different genotypes. A. phagocytophilum was present in all tested flocks with the infection prevalence ranging from 0.9% to 5.7%. None of the tested questing ticks carried A. ovis. A. phagocytophilum was detected in 1.1% and 7.8% of questing Ixodes ricinus ticks collected around the farms located in southeastern and northern Slovakia, respectively. A. phagocytophilum revealed higher intraspecific diversity than A. ovis.

Detection of Anaplasma phagocytophilum and Borrelia burgdorferi sensu lato in dogs in the Czech Republic.

The aim of this study is to present molecular, serologic, and clinical findings for dogs that were naturally infected with Anaplasma phagocytophilum or Borrelia burgdorferi sensu lato (s. l.) in the Czech Republic. This data can provide information relevant to human infection. In total, blood samples from 296 dogs and 118 engorged ticks were examined. Samples were tested for A. phagocytophilum using polymerase chain reaction (PCR) amplification, nested PCR, and direct sequencing of the 16S rDNA, and for B. burgdorferi s. l. using PCR amplification of the 16S rDNA and restriction fragment length polymorphism analysis of the 5S-23S rDNA intergenic spacer. In addition, blood samples were screened for antibodies to these bacteria. Ten (3.4%) dogs were PCR-positive for A. phagocytophilum. Morulae of A. phagocytophilum in granulocytes were found in two of these dogs. Nine of the PCR-positive dogs had clinical signs related to anaplasmosis. Statistically significant differences in the PCR detection rates were found between breeds and between symptomatic and asymptomatic dogs. Infection with Borrelia garinii was detected by PCR in a dog with meningoencephalitis. DNA of A. phagocytophilum and B. burgdorferi s. l. (B. garinii or Borrelia afzelii) was detected in 8.5% and 6.8% of ticks, respectively. Immunoglobulin (Ig) G seropositivity to A. phagocytophilum was 26%. Significant differences were found with respect to breed and gender. IgM and IgG antibodies to B. burgdorferi s. l. were detected in 2.4% and 10.3% of dogs, respectively. Our findings suggest that the exposure to B. burgdorferi s. l. exists in dogs in the Czech Republic, and exposure to A. phagocytophilum is common.