Epidemiology of feline bartonellosis and molecular characteristics of Bartonella henselae in Bangladesh

Abstract

Bartonellosis, a neglected vector-borne zoonotic disease transmitted from animals to humans, continues to threaten human and animal health significantly. This study aims to determine the epidemiology of feline bartonellosis and the molecular characteristics of Bartonella spp. in cats. From June 2018 to June 2020, 304 oral swabs were randomly collected from Bangladesh's Dhaka, Mymensingh, and Rajshahi districts. A pre-tested questionnaire was administered to collect data. Oral swabs were subjected to PCR targeting htrA gene to confirm Bartonella spp., which was subsequently validated through sequencing. Risk factors were identified using multivariable logistic regression analysis. The overall prevalence of feline bartonellosis was found to be 15.1 %. The following factors were significantly (p < 0.05) associated with Bartonella infection in risk factor analysis: cats aged ≥ 1 year (OR: 3.23, 95 % CI: 1.38-24.40), local breed cats (OR: 3.37, 95 % CI: 1.05-10.81), cats carrying fleas (OR: 2.33, 95 % CI: 1.93-13.45), antifleacidal drugs inconsistently administered cats (OR: 6.74, 95 % CI: 3.17-14.31), outdoor access cats (OR: 2.54, 95 % CI: 1.16-5.57). Notably, zoonotic B. henselae was confirmed through sequencing, establishing it as the causal agent of cat scratch disease. Phylogenetic analysis showed homology with B. henselae sequences from Brazil, Saint Kitts, and Nevis. We recommend consistent and appropriate flea control measures to curb its spread among Bangladeshi cats. Moreover, limiting outdoor exposure or implementing preventive measures for outdoor cats could reduce the disease burden. The associated human health risk can be decreased by effectively controlling this disease within the cat population.

Keywords: Bartonellosis; Cat scratch disease; Epidemiology; htrA genes.

Fig. 1

The map of Bangladesh shows the sampling areas for the bartonellosis study in cats.

Fig. 2

This figure represents the PCR amplification of DNA of Bartonella spp. Lane M- 100 bp DNA ladder Lane 1–11: Complies with the samples of Bartonella spp showing approximately 414 bp. NC-Negative control, PC: Positive control (Houston-1; ATCC 49882).

Fig. 3

The Neighbor-Joining tree based on a 414 bp segment of the htrA gene of Bartonella spp. The optimal tree is shown with the percentage of replicate trees from the bootstrap test (1000 replicates), indicating how often the associated taxa clustered together. The tree is drawn to scale, with branch lengths reflecting the evolutionary distances used to establish the phylogenetic relationships. These distances are calculated using the Jukes-Cantor method and are measured units of base substitutions per site. A gamma distribution (shape parameter = 5) accounted for rate variation among sites. This analysis involved 12 nucleotide sequences, considering all codon positions (1st, 2nd, and 3rd). Gaps and missing data were excluded (complete deletion option), resulting in a final dataset of 388 positions. These evolutionary analyses were conducted using MEGA11 software.