Bartonella are vector-borne parasitic bacteria that cause zoonotic infections in humans. One of the most common infections is cat-scratch disease caused by Bartonella henselae and Bartonella clarridgeiae. Cats are the major reservoir for these two species of bacteria, while cat fleas are vectors for the transmission of infection agents among cats. The aim of the present study was to investigate the presence of Bartonella infections in stray and pet cats and in cat fleas in Lithuania. Blood samples were taken from 163 cats presented in pet clinics and animal shelters. A total of 102 fleas representing two species, Ctenocephalides felis and Ctenocephalides canis, were collected from 12 owned cats that live both outdoors and indoors. Bartonella DNA in samples was detected using a nested PCR targeting the 16S–23S rRNA intergenic spacer (ITS) region. Bartonella DNA was detected in 4.9% (8/163) of the cats and 29.4% (30/102) of the fleas. Sequence analysis of the ITS region showed that the cats and fleas were infected with B. henselae, B. clarridgeiae and Bartonella sp., closely related to B. schoenbuchensis. This study is the first report on the prevalence and molecular characterization of Bartonella spp. in cats and cat fleas in Lithuania.

Mycoplasma spp. pathogens frequently cause chronic and acute diseases in cats. The aim of the present study was to investigate the presence and genetic diversity of Mycoplasma spp. in cats and their ectoparasites using PCR and sequence analysis of the 16S rRNA gene. Blood samples were collected from 541 domestic and stray cats in Lithuania. Ectoparasites (153 fleas and 321 ticks) were collected from owned domestic cats that live both outdoors and indoors. Mycoplasma spp. were detected in 7.2% of cat blood samples and 4.4% of Ctenocephalides felis fleas. The sequence analysis revealed the presence of Mycoplasma haemofelis in 1.1% of cats and ‘Candidatus Mycoplasma haematominutum’ in 4.8% of cats. Ct. felis fleas harboured M. haemofelis. To the best of the authors’ knowledge, this is the first report on the prevalence and molecular characterisation of Mycoplasma bacteria in cats in Lithuania and cat fleas in the Baltic States.

Canine babesiosis is an emerging and rapidly expanding tick-borne disease in central and northeast Europe. In the last two decades, the endemic area of Babesia canis has expanded from central Europe to the Baltic region. This study aimed to investigate the genetic diversity of B. canis strains isolated from naturally infected dogs in different regions of Lithuania using PCR-RFLP and sequence analyses based on a partial region of 18S rRNA and Bc28.1 genes. Blood samples from 149 dogs suspected of having babesiosis were collected in Lithuania during 2016–2017. Based on PCR-RFLP profiles and two nucleotide substitutions observed in 18S rRNA gene sequences, three B. canis genotypes were identified in Lithuania—18S rRNA-A, 18S rRNA-B and 18S rRNA-A/B—with the A/B genotype predominating (83.9%). Based on the obtained PCR-RFLP profiles of the Bc28.1 gene, four B. canis genotypes were identified: Bc28.1-B (53.8%), Bc28.1-34 (20.8%), Bc28.1-A (17.9%), and Bc28.1-34/A or B (7.5%). Sequence analysis of the partial Bc28.1 gene revealed eighteen polymorphic sites and thirteen sequence variants among the Lithuanian samples. The B. canis genotypes obtained were detected with varying prevalences in different regions of Lithuania.

Tick-borne diseases are an increasing public health concern in Europe, driven by climate change, landscape transformation, and expanding human activity. Urban green spaces provide suitable habitats for ticks and increase human exposure to tick-borne pathogens (TBPs), yet habitat-specific patterns in urban and suburban environments remain poorly characterized. This study examined tick distribution and TBPs prevalence across 11 urban and suburban sites in Kaunas County, Lithuania. A total of 1539 questing Ixodes ricinus ticks were collected and screened by real-time PCR for Borrelia spp., Anaplasma phagocytophilum, Neoehrlichia mikurensis, Rickettsia spp., and Babesia spp., with further species identification by sequencing. Borrelia spp. were most prevalent (24.43%), followed by Rickettsia spp. (7.60%), N. mikurensis (6.63%), A. phagocytophilum (3.64%), and Babesia spp. (2.53%). Tick density, pathogen prevalence, and species diversity varied among habitats, with higher values in forested and ecotonal areas, but notable infection rates were also observed in managed urban sites. Co-infections occurred in 18.8% of infected ticks. Our findings demonstrate that the circulation of TBPs in urban and suburban landscapes is shaped by local habitat features, host communities, and management intensity, highlighting the need for habitat-specific risk assessment in urban planning and public health.

Neoehrlichia mikurensis and Anaplasma phagocytophilum, both members of the Anaplasmataceae family, are pathogens that can cause diseases in animals and humans. Ixodid ticks are the primary vectors for both species. While urban green spaces offer various ecological and social benefits, there is increasing evidence suggesting potential public health risks, particularly increased exposure to vector-borne diseases. The aim of the present study was to assess the prevalence and co-occurrence of A. phagocytophilum and N. mikurensis in ticks from urban environments in Lithuania. A total of 3599 Ixodes ricinus and 29 Dermacentor reticulatus were collected from 31 urban and 21 peri-urban areas. Ticks were examined for pathogens using duplex real-time PCR. Anaplasma phagocytophilum was detected in 4.47% of tested ticks, while N. mikurensis in 6.17%. Co-infection was found in 0.42% of I. ricinus specimens. Phylogenetic analysis of the groEl gene revealed low genetic variability of N. mikurensis and the circulation of two ecotypes (I and II) of A. phagocytophilum. Additionally, Ehrlichia muris was identified in I. ricinus ticks. This study is the first report of N. mikurensis detection in ticks from Lithuania. Our findings highlight the potential risk posed by tick-borne pathogens in urban and peri-urban areas of the country.