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Background: Critically ill patients are at increased risk of health care-associated infections due to various devices (central line-associated bloodstream infection, catheter-associated urinary tract infection, and ventilator-associated pneumonia), which pose a significant threat to this population. Among several strategies, daily bathing with chlorhexidine digluconate, a water-soluble antiseptic, has been studied as an intervention to decrease the incidence of health care-associated infections in the intensive care unit; however, its ability to reduce all health care-associated infections due to various devices is unclear. We designed the Daily Chlorhexidine Bath for Health Care Associated Infection Prevention (CLEAN-IT) trial to assess whether daily chlorhexidine digluconate bathing reduces the incidence of health care-associated infections in critically ill patients compared with soap and water bathing., Methods: The CLEAN-IT trial is a multicenter, open-label, cluster randomized crossover clinical trial. All adult patients admitted to the participating intensive care units will be included in the trial. Each cluster (intensive care unit) will be randomized to perform either initial chlorhexidine digluconate bathing or soap and water bathing with crossover for a period of 3 to 6 months, depending on the time of each center's entrance to the study, with a 1-month washout period between chlorhexidine digluconate bathing and soap and water bathing transitions. The primary outcome is the incidence of health care-associated infections due to devices. The secondary outcomes are the incidence of each specific health care-associated infection, rates of microbiological cultures positive for multidrug-resistant pathogens, antibiotic use, intensive care unit and hospital length of stay, and intensive care unit and hospital mortality., Conclusion: The CLEAN-IT trial will be used to study feasible and affordable interventions that might reduce the health care-associated infection burden in critically ill patients.

In several urban and peri‑urban areas of Brazil, populations of Amblyomma sculptum and Amblyomma dubitatum ticks are maintained by capybaras (Hydrochoerus hydrochaeris). In some of these areas, this host and these tick species are associated with Brazilian spotted fever (BSF), a lethal human disease caused by the bacterium Rickettsia rickettsii. In this work, we evaluated the risk of human exposure to these tick species using four collection techniques to discern host-seeking behavior. The study was carried out in 10 urban sites inhabited by capybaras in Uberlândia, a BSF-free municipality in southeastern Brazil. Ticks were collected in areas of 400 m 2 at each site and at three seasons. Within the same municipality, the distance and speed of A. sculptum nymphs moving towards the CO 2 traps were evaluated. In a sample of ticks Rickettsia DNA was investigated. During the study period, 52,953 ticks were collected. Among these, 83.4 % were A. sculptum (1,523 adults, 10,545 nymphs and 32,104 larvae) and 16.6 % were A. dubitatum (464 adults, 2,153 nymphs and 6,164 larvae). An average annual questing tick density of 4.4/m² was observed, with the highest density recorded at one site in autumn (31.8/m²) and the lowest in summer at another site (0.03/m²). The visual search yielded the highest proportion of A. sculptum larvae, constituting 47 % of the total and 63.6 % of all A. sculptum larvae. In contrast, CO 2 traps collected a greater proportion of nymphs and adults of A. sculptum ticks. In the case of A. dubitatum, the CO 2 trap was the most efficient technique with 57.7 % of captures of this species, especially of nymphs (94.5 % of captures) and adults (97.8 % of captures). Ticks' ambush height on vegetation (9 to 77 cm), observed by visual search 30 times, yielded a total of 20,771 ticks. Of these, 28 (93 %) were A. sculptum ticks, with only two (7 %) identified as A. dubitatum ticks. Among A. sculptum ticks, the nymph was the most attracted stage to humans and larva in the case of A. dubitatum. Amblyomma sculptum adults and nymphs were significantly more attracted to humans than those of A. dubitatum, but A. dubitatum larvae were significantly more attracted than the same stage of A. sculptum. The maximum distance and speed of horizontal displacement for A. sculptum nymphs were five meters and 2.0 m/h, respectively. The only species of Rickettsia detected in ticks, exclusively in A. dubitatum, was R. bellii. Importantly, it was observed that the higher the proportion of A. sculptum in the community of ticks, the lower the rate of infection of A. dubitatum by R. bellii. In conclusion, host-seeking behavior differed between the two tick species, as well as between stages of the same species. A greater restriction of A. dubitatum ticks to the soil was observed, while larvae and nymphs of A. sculptum dispersed higher in the vegetation. The behavior presented by A. sculptum provides greater opportunities for contact with the hosts, while A. dubitatum depends more on an active search for a host, the hunter behavior. Taken together, these observations show that a human being crossing an area infested with A. sculptum and A. dubitatum ticks will have almost exclusive contact with A. sculptum larvae and/or nymphs. Humans in a stationary position (sitting, lying or immobile) are exposed to both tick species, but they are more attractive to adults and mainly nymphs of A. sculptum compared to the corresponding stages of the tick A. dubitatum. The negative effect of A. sculptum on A. dubitatum infection by R. bellii deserves further studies., Competing Interests: Declaration of competing interest The authors declared that no competing interests exist., (Copyright © 2024. Published by Elsevier GmbH.)

Ticks are obligate hematophagous parasites that can transmit to vertebrate hosts several pathogens, including viruses, bacteria, protozoa and helminths. Among these agents, some Borrelia species some Borrelia species cause disease in humans and other vertebrate hosts; therefore, they have medical and veterinary health importance. To gather additional information on Borrelia species in Brazil, the current study aimed to detect the presence of these species in Ornithodoros cavernicolous ticks collected in September 2019 from cement pipes that are used by bats as shelter in a farm located in the midwestern region of Brazil. DNA samples obtained from 18 specimens of O. cavernicolous were subjected of two polymerase chain reactions, targeting a segment of the Borrelia fla B gene. Of the samples tested, only one (6 %, 1/18) showed amplification. The nucleotide sequence of the amplified DNA showed more than 97 % (293/300) identity with a sequence of a Borrelia sp. detected in blood collected from a bat from Macaregua Cave, Colombia, and more than 97 % (292/300) detected in lungs from vampire bats from northeastern Brazil. The deduced amino acid sequences were identical to each other. Phylogenetic analysis indicated that these sequences formed a group of Borrelia species (putatively associated with bats) that is closely related to sequences of Borrelia species of the Lyme borreliosis group. Further investigations should be carried out in order to determine whether the sequence of the Borrelia sp. we found belongs to a new taxon. It will also be of great importance to determine which vertebrate hosts, besides bats, O. cavernicolous ticks can parasitize in order to investigate whether the Borrelia sp. we found may be transmitted and cause disease to the other vertebrate hosts., Competing Interests: Declaration of Competing Interest The authors have no relevant financial or non-financial interests to disclose., (Copyright © 2023. Published by Elsevier GmbH.)

In Brazil, recent studies have reported viruses detected in ticks with pathogenic potential in vertebrate hosts. Ticks of the species Rhipicephalus microplus collected from bovines in a savannah area were tested by RT-PCR for the presence of RNA targetting a segment of NS3-like protein gene of Mogiana tick virus, a member of the recently-described Jingmenvirus group. Amplification with size similar to the expected was observed with 25% (7/28) RNA samples of ticks that were collected from 39% (7/18) of the bovines. Nucleotide sequence analysis of three PCR products revealed divergence that varied from 3.3 to 5.0% in a single farm. Although Jingmen tick virus, another member belonging to the Jingmenvirus group, has been detected in human patients with Crimean-Congo hemorrhagic fever in Kosovo, whether or not MGTV causes disease in cattle and other animals remains to be investigated., (Copyright © 2018 Elsevier GmbH. All rights reserved.)