Detection of Candidatus Bartonella odocoilei n. sp. in Lipoptena mazamae associated with white-tailed deer in Campeche, Mexico

Detection of Bartonella bovis DNA in blood samples from a veterinarian in Mexico

The genus Bartonella encompasses 38 validated species of Gram-negative, facultative intracellular bacteria that colonize the endothelial cells and erythrocytes of a wide spectrum of mammals. To date, 12 Bartonella species have been recorded infecting humans, causing diseases of long historical characterization, such as cat scratch fever and trench fever, and emerging bartonellosis that mainly affect animal health professionals. For this reason, this study aimed to report a documented case of Bartonella bovis infecting a veterinarian from Mexico by the amplification, sequencing and phylogenetic reconstruction of the citrate synthase (gltA) and the RNA polymerase beta-subunit (rpoB) genes, and to report the natural course of this infection. To our knowledge, this work is the first to report the transmission of B. bovis via needlestick transmission to animal health workers in Latin America.

The New Haplotypes of Bartonella spp. and Borrelia burgdorferi Sensu Lato Identified in Lipoptena spp. (Diptera: Hippoboscidae) Collected in the Areas of North-Eastern Poland

Deer keds are hematophagous ectoparasites (Diptera: Hippoboscidae) that mainly parasitize Cervidae. These flies are particularly important for animal health due to the occurrence of numerous pathogenic microorganisms. They may also attack humans and their bites may cause allergenic symptoms. The aim of the study was to identify the molecular characteristics of Borrelia burgdorferi sensu lato and Bartonella spp. pathogens detected in Lipoptena spp. sampled both from the hosts and from the environment. For identification of Bartonella spp and B. burgdorferi s. l., the primers specific to the rpoB and flaB gene fragments were used, respectively. The overall prevalence of B. burgdorferi s.l. DNA in Lipoptena cervi was 14.04%, including 14.8% infection in the tested group of winged specimens. The overall prevalence of Bartonella spp. was 57.02%. The presence of these bacteria was detected in 53.5% of specimens of L. cervi and 75.7% of L. fortisetosa. The phylogenetic analysis showed five new haplotypes of the rpoB gene of Bartonella sp. isolated from L. cervi/Lipoptena fortisetosa. We also identified one new haplotype of B. afzelii and three haplotypes of B. burgdorferi isolated from winged specimens of L. cervi. This is the first study to detect the genetic material of B. burgdorferi s.l. in L. cervi in Poland and the first report on the identification of these bacteria in host-seeking specimens in the environment.

Emerging rodent-associated Bartonella: a threat for human health?

Background

Species of the genus Bartonella are facultative intracellular alphaproteobacteria with zoonotic potential. Bartonella infections in humans range from mild with unspecific symptoms to life threatening, and can be transmitted via arthropod vectors or through direct contact with infected hosts, although the latter mode of transmission is rare. Among the small mammals that harbour Bartonella spp., rodents are the most speciose group and harbour the highest diversity of these parasites. Human–rodent interactions are not unlikely as many rodent species live in proximity to humans. However, a surprisingly low number of clinical cases of bartonellosis related to rodent-associated Bartonella spp. have thus far been recorded in humans.

Methods

The main purpose of this review is to determine explanatory factors for this unexpected finding, by taking a closer look at published clinical cases of bartonellosis connected with rodent-associated Bartonella species, some of which have been newly described in recent years. Thus, another focus of this review are these recently proposed species.

Conclusions

Worldwide, only 24 cases of bartonellosis caused by rodent-associated bartonellae have been reported in humans. Possible reasons for this low number of cases in comparison to the high prevalences of Bartonella in small mammal species are (i) a lack of awareness amongst physicians of Bartonella infections in humans in general, and especially those caused by rodent-associated bartonellae; and (ii) a frequent lack of the sophisticated equipment required for the confirmation of Bartonella infections in laboratories that undertake routine diagnostic testing. As regards recently described Bartonella spp., there are presently 14 rodent-associated Candidatus taxa. In contrast to species which have been taxonomically classified, there is no official process for the review of proposed Candidatus species and their names before they are published. This had led to the use of malformed names that are not based on the International Code of Nomenclature of Prokaryotes. Researchers are thus encouraged to propose Candidatus names to the International Committee on Systematics of Prokaryotes for approval before publishing them, and only to propose new species of Bartonella when the relevant datasets allow them to be clearly differentiated from known species and subspecies.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s13071-022-05162-5.