Bartonellosis: A one health perspective

Abstract

Recently, Bartonella, a genus comprised of fastidious, Gram-negative, intracellular bacteria, has rapidly expanded from approximately 4-5 species in the 1990s to 30-40 named or proposed species that are currently described in the literature. While Bartonellae are highly adapted to a number of mammalian reservoir hosts, substantial genetic diversity allows for the transmission of Bartonella to humans (i.e. a zoonosis) and other non-reservoir hosts. Improvements in the diagnostic sensitivity of laboratory tests have allowed researchers to identify a spectrum of Bartonella species in novel host species, including domestic animals and wildlife. Because Bartonella can infect a spectrum of accidental hosts, it is imperative that researchers determine the consequences of Bartonella spp. infection on new host populations and the impact of this genus during environmental changes, particularly natural disasters. Rapid, accurate diagnostic tests now afford researchers and clinicians the ability to conduct more reliable epidemiologic and treatment related studies that will better characterize the outcomes of Bartonella spp. infection in animals and human patients. Prevalence studies have shown that Bartonella spp. DNA can be found in numerous arthropods, though additional research is required to identify epidemiologically important competent vectors of Bartonella spp. transmission. Future Bartonella spp. research initiatives should strive to not only identify the bacterium in arthropod and host populations, but also to combine those data with epidemiologically relevant case data and ecological risk assessment. Combined efforts from professionals in animal and human medicine, vector ecology, pathogen evolution, microbial ecology, and sociology are necessary in order to create the veterinary and medical infrastructure, training, prevention, and surveillance required to thoroughly understand Bartonella spp. ecology, dynamics and control. Bartonellosis may prove to be one of the most important One Health emerging zoonotic diseases of the next decade.