Molecular detection of Bartonella coopersplainsensis and B. henselae in rats from New Zealand

AIM: To identify Bartonella spp. in rats from New Zealand using molecular methods. METHODS: DNA was extracted from the spleens of 143 black rats (Rattus rattus) captured in the Tongariro National Park, New Zealand. PCR was performed using Bartonella genus-specific primers amplifying segments of the 16S-23S rRNA internal transcribed spacer and citrate synthase (gltA) and beta subunit of the RNA polymerase (rpoB) genes. PCR products were sequenced and compared online with sequences stored in the database of the National Center for Biotechnology Information of the United States of America. RESULTS: DNA sequences matching Bartonella coopersplainsensis and B. henselae were detected in samples from 22/143 (15.4%) and 3/143 (2.1%) rats, respectively. Co-occurrence of B. coopersplainsensis and B. henselae sequences was observed in the sample from one rat. CONCLUSIONS AND CLINICAL RELEVANCE: Gram-negative fastidious bacteria belonging to the genus Bartonella are associated with a range of human diseases. Rodents play an important role as reservoirs of a broad range of Bartonella species. To our knowledge, this is the first report of a molecular detection of Bartonella spp. DNA in rodents from New Zealand, and the first identification of B. henselae DNA in rats, worldwide. Whereas the public health significance of B. coopersplainsensis remains undefined, B. henselae is the agent of cat scratch disease, and the presence of this bacterium in rats may have public health implications. Our results are preliminary and additional analyses of larger samples, preferably by bacterial culture, would provide more information on the prevalence and diversity of Bartonella spp., in particular B. henselae, in rats.