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Soft ticks in the genus Ornithodoros occur throughout the Mojave Desert in southern Nevada, southeastern California, and parts of southwestern Utah and northwestern Arizona, USA, and are frequently observed parasitizing Mojave desert tortoises (Gopherus agassizii). However, limited research exists examining the relationship between ticks and desert tortoises. Mojave desert tortoises are listed as threatened by the US Fish and Wildlife Service, and as such, their populations are monitored and individual tortoise health is routinely assessed. These health assessments document the presence and abundance of ticks present on tortoises, but detailed examination of the relationship between ticks and tortoise health has been lacking. This study analyzed the relationship between tick presence and desert tortoise health assessments as a function of season, location, age (adult vs. juvenile), foraging behavior, evidence of clinical signs of disease, body condition score, and sex. Our results indicate that more ticks were found on tortoises in the summer than in any other season. Ticks were observed more frequently on captive tortoises versus wild tortoises, and more ticks were likely to be present on adult tortoises than on juveniles. Ticks were also more likely to be observed on tortoises that lacked evidence of foraging and on tortoises with observed clinical signs of disease. These findings provide valuable insights into the biology of ticks in relation to tortoises that may be useful for management of both captive and free-living threatened tortoise populations where ticks are detected. Our study also may improve understanding of potential tick-borne disease dynamics in the Mojave desert tortoise habitat, including Borrelia sp. carried by Ornithodoros ticks, which cause tick- borne relapsing fever in people. [ABSTRACT FROM AUTHOR]

Borrelia miyamotoi is a spirochete that causes a relapsing febrile illness and is transmitted by hard Ixodes species ticks (1,2). B. miyamotoi is prevalent in western black-legged tick (I. pacificus) [...]

Anaplasma phagocytophilum is a tick-transmitted bacterial pathogen of humans and other animals, and is an obligate intracellular parasite. Throughout the course of infection, hosts acquire temporary resistance to granulocytic anaplasmosis as they develop immunity specific for the major antigen, major surface protein 2 (Msp2). However, the bacterium then utilizes a novel recombination mechanism shuffling functional pseudogenes sequentially into an expression cassette with conserved 5' and 3' ends, bypassing host immunity. Approximately 100 pseudogenes are present in the only fully sequenced human-origin HZ genome, representing the possibility for almost unlimited antigenic diversity. In the present study, we identified a select group of 20% of the A. phagocytophilum HZ msp2 pseudogenes that have matched preferentially to human, canine, and equine expression cassettes. Pseudogenes cluster predominantly in one spatial run limited to a single genomic island in less than 50% of the genome but phylogenetically related pseudogenes are neither necessarily located in close proximity on the genome nor share similar percent identity with expression cassettes. Pseudogenes near the expression cassette (and the origin) are more likely to be expressed than those farther away. Taken together, these findings suggest that there may be natural selection pressure to retain pseudogenes in one cluster near the putative origin of replication, even though global recombination shuffles pseudogenes around the genome, separating pseudogenes that share genetic origins as well as those with similar identities.

Bartonella rochalimae was first isolated from the blood of a human who traveled to Peru and was exposed to multiple insect bites. Foxes and dogs are likely natural reservoirs for this bacterium. We report the results of experimental inoculation of two dogs, five cats and six guinea pigs with the only human isolate of this new Bartonella species. Both dogs became bacteremic for 5-7 weeks, with a peak of 10(3)-10(4) colony forming units (CFU)/mL blood. Three cats had low bacteremia levels (< 200 CFU/mL) of 6-8 weeks' duration. One cat that remained seronegative had two bacterial colonies isolated at a single culture time point. A fifth cat never became bacteremic, but seroconverted. None of the guinea pigs became bacteremic, but five seroconverted. These results suggest that dogs could be a reservoir of this strain of B. rochalimae, in contrast to cats and guinea pigs.

Microbial biofilms can establish in numerous areas within the brewery and exposure to these communities of organisms can result in undesirable flavors. Beer transfer lines represent a particular risk for contamination as the lines provide an effective point of nucleation for biofilm colonization if they have been subject to degradation and are not well maintained. Despite the presence of surface imperfections associated with prolonged use, transfer tubing in place for several months within a canning operation was observed to be significantly less capable of hosting microbial growth than comparable tubing that had not been exposed to the product, suggesting that the industrial practice itself had imparted an antibiofilm character to the tubing not originally present in new lines. Using an in vitro assay designed to reconstitute microbial biofouling in this tubing, transfer lines artificially conditioned with beer served to effectively reduce biofouling by the hop acid resistant microorganism Lactobacillus brevis compared to untreated controls. The observed reduction in microbial growth was more pronounced in lines that had been conditioned with highly-hopped beer than moderately-hopped beer. Tubing conditioned with aqueous solutions of hop extracts or hop-associated terpenoid compounds also exhibited a relative resistance to microbial growth. Pre-treatment of tubing with solutions containing major (terpene hydrocarbons) and minor (oxygenated terpenes) hop- associated terpenes reduced L. brevis biofouling relative to untreated controls. Results indicate that conditioning of beer tubing with simple solutions of these compounds may provide a means of protecting against biofouling. [ABSTRACT FROM AUTHOR]

A total of 2,121 small mammals in California were assessed for Anaplasma phagocytophilum from 2006 through 2008. Odds ratios were >1 for 4 sciurids species and dusky-footed woodrats. High seroprevalence [...]

Wound healing attempts to maintain homeostasis in the wound while minimizing the risk of infection to the tissue by foreign agents, such as opportunistic bacterial pathogens. Biofilms established by these pathogens are a common cause of chronic infections that slow the healing process. Preparation of skin wound healing devices comprised of electrospun proteins associated with skin have been shown to accelerate the healing process relative to conventional wound dressings. In this work, we have developed electrospinning methods to incorporate the antimicrobial ionic liquid/deep eutectic solvent choline geranate (CAGE) into these devices. Integration of CAGE into the dressing material was verified via 1H nuclear magnetic resonance spectrometry, and the effect on the material property of the resultant devices were assessed using scanning electron microscopy. CAGE‐containing devices demonstrate a concentration‐dependent inactivation of exogenously applied solutions of both gram‐positive and gram‐negative pathogens (Enterococcus sp and Pseudomonas aeruginosa, respectively), but maintain their ability to serve as a compatible platform for proliferation of human dermal neonatal fibroblasts. [ABSTRACT FROM AUTHOR]

Background Tick-borne relapsing fever (TBRF) is a neglected zoonotic bacterial disease known to occur on 5 continents. We report a laboratory-acquired case of TBRF caused by Borrelia caucasica , which is endemic in Ukraine and transmitted by Ornithodoros verrucosus ticks. Methods We isolated spirochetes and characterized them by partially sequencing the 16s ribosomal ribonucleic acid (rrs), flagellin (flaB), and deoxyribonucleic acid gyrase (gyrB) genes and conducting a phylogenetic analysis. Results These analyses revealed a close relationship of Ukrainian spirochetes with the Asian TBRF species, Borrelia persica. The taxonomic and nomenclature problems related to insufficient knowledge on the spirochetes and their vectors in the region are discussed. Conclusions Although these findings enhance our understanding of species identities for TBRF Borrelia in Eurasia, further work is required to address the neglected status of TBRF in this part of the world. Public health practitioners should consider TBRF and include the disease into differential diagnosis of febrile illnesses with unknown etiology. [ABSTRACT FROM AUTHOR]

To the Editor: In northwestern California, USA, the western blacklegged tick, Ixodes pacificus, is a known vector of Borrelia burgdorferi, the spirochete that causes Lyme disease. B. miyamotoi, which is [...]

To the Editor: Anaplasma phagocytophilum was defined to include Ehrlichia phagocytophila, E. equi, and the agent of human granulocytic ehrlichiosis. Nevertheless, we and others have found phenotypic and genetic differences [...]