Molecular screening of cat and dog ectoparasites for the presence of Bartonella spp. in Attica, Greece

Molecular prevalence and genetic diversity of Bartonella spp. in stray cats of İzmir, Turkey

Background

Bartonella spp. are vector-borne pathogens that cause zoonotic infections in humans. One of the most well-known of these is cat-scratch disease caused by Bartonella henselae and Bartonella clarridgeiae, with cats being the major reservoir for these two bacteria. Izmir, Turkey is home to many stray cats, but their potential role as a reservoir for the transmission of Bartonella to humans has not been investigated yet. Therefore, the aim of this study was to investigate the prevalence of Bartonella species and their genetic diversity in stray cats living in Izmir.

Methods

Molecular prevalence of Bartonella spp. in stray cats (n = 1012) was investigated using a PCR method targeting the 16S-23S internal transcribed spacer gene (ITS), species identification was performed by sequencing and genetic diversity was evaluated by haplotype analysis.

Results

Analysis of the DNA extracted from 1012 blood samples collected from stray cats revealed that 122 samples were Bartonella-positive, which is a molecular prevalence of 12.05% (122/1012; 95% confidence interval [CI] 10.1–14.2%). Among the Bartonella-positive specimens, 100 (100/122; 81.96%) were successfully sequenced, and B. henselae (45/100; 45%), B. clarridgeiae (29/100; 29%) and Bartonella koehlerae (26/100; 26%) were identified by BLAST and phylogenetic analyses. High genetic diversity was detected in B. clarridgeiae with 19 haplotypes, followed by B. henselae (14 haplotypes) and B. koehlerae (8 haplotypes).

Conclusions

This comprehensive study analyzing a large number of samples collected from stray cats showed that Bartonella species are an important source of infection to humans living in Izmir. In addition, high genetic diversity was detected within each Bartonella species.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13071-022-05431-3.

Prevalence and Risk Factors for Bartonella spp. and Haemoplasma Infections in Cats from Greece

Simple Summary

Bartonellosis and haemoplasmosis are diseases with global impact on the health of domestic cats and of zoonotic importance. This is the first study investigating the risk factors for Bartonella spp. and haemoplasma species infections in cats from Greece. In addition, this study determined the serologic and molecular prevalence of Bartonella spp. and haemoplasma species infections in different populations of cats living in different regions of Greece. A total of 452 cats were enrolled into the study. Blood was collected from each cat for the serological detection of Bartonella henselae antibodies and the molecular detection of Bartonella spp. and haemoplasma species infections. Overall, the seroprevalence of B. henselae was 35.4%, while the molecular prevalence of Bartonella spp. and haemoplasma species was 2.9% and 19%, respectively. The results of this study indicate that cats with partial or exclusive outdoor access and cats with flea infestation are at the greatest risk for B. henselae seropositivity. Furthermore, cats living in warmer regions such as Attica and Crete are at the greatest risk. Lack of ectoparasiticide use was identified as a risk factor for haemoplasma species infection. This suggests that the use of ectoparasiticides in cats may be an effective means of preventing haemoplasma species infection in cats.

Abstract

Bartonellosis and haemoplasmosis are vector-borne diseases with global impact on the health of domestic cats and of zoonotic importance. The aim of this study was to describe the epidemiological aspects of various populations of cats infected with Bartonella spp. or haemoplasma species. The populations evaluated included client-owned cats, stray cats and cats that live in breeding catteries in Greece. A total of 452 cats were prospectively enrolled into the study. A commercially available indirect immunofluorescence antibody testkit was used for the detection of Bartonella henselae IgG antibodies in serum. PCRs for the detection of Bartonella spp. and haemoplasma species DNA in the blood were also performed in a subgroup of 242 of the 452 cats. Risk factors for B. henselae seropositivity and infection with the haemoplasma species were determined using multivariable analysis. Overall, 160 (35.4%) of the 452 cats were seropositive for B. henselae. Seven (2.9%) and 46 (19%) of the 242 cats were PCR-positive for Bartonella spp. and haemoplasma species, respectively. The factors associated with B. henselae seropositivity, based on multivariate analysis, included older age, outdoor access, living region and flea infestation. Non-administration of ectoparasiticides was associated with haemoplasma species infection. This study shows a high prevalence of seropositivity for B. henselae and a relatively high prevalence of infection with haemoplasma species. Therefore, it is necessary to establish optimal strategies for the prevention of Bartonella spp. and haemoplasma species infections, considering the high-risk groups of cats identified in this study.

Molecular Survey of Bartonella Species in Stray Cats and Dogs, Humans, and Questing Ticks from Portugal

Bartonella spp. comprises emergent and re-emergent fastidious Gram-negative bacteria with worldwide distribution. Cats are the main reservoir hosts for Bartonella henselae and dogs represent opportunistic hosts for the bacteria. Even though ticks may also play a role in transmission, their competence as vectors for Bartonella spp. has not been totally understood. Considering only a few studies had a focus on screening Bartonella in animals, humans and ectoparasites in Portugal, this study aimed to address the molecular occurrence of Bartonella sp. in 123 stray cats, 25 stray dogs, 30 humans from Lisbon and 236 questing ticks within the country. Using a qPCR targeting the nuoG gene, it was possible to detect Bartonella sp. DNA on 20.32% of cat samples (25/123). From these positive samples, 13 sequences were characterized as B. henselae, 11 as B. clarridgeiae and 1 presented co-infection with both species. The absolute quantification of nuoGBartonella DNA in sampled cats ranged from 2.78 × 10 to 1.03 × 10⁵ copies/µL. The sampled dogs, humans and ticks were negative. These results showed that B. henselae and B. clarridgeiae are circulating in stray cats from Lisbon. Additional and more extended studies should be conducted to determine the impact of such infections on humans, particularly those in constant and direct contact with cats.