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Chikungunya virus (CHIKV) is an emerging, mosquito-borne alphavirus responsible for acute to chronic arthralgias and neuropathies. Although it originated in central Africa, recent reports of disease have come from many parts of the world, including the Americas. While limiting human CHIKV cases through mosquito control has been used, it has not been entirely successful. There are currently no licensed vaccines or treatments specific for CHIKV disease, thus more work is needed to develop effective countermeasures. Current animal research on CHIKV is often not representative of human disease. Most models use CHIKV needle inoculation via unnatural routes to create immediate viremia and localized clinical signs; these methods neglect the natural route of transmission (the mosquito vector bite) and the associated human immune response. Since mosquito saliva has been shown to have a profound effect on viral pathogenesis, we evaluated a novel model of infection that included the natural vector, Aedes species mosquitoes, transmitting CHIKV to mice containing components of the human immune system. Humanized mice infected by 3–6 mosquito bites showed signs of systemic infection, with demonstrable viremia (by qRT-PCR and immunofluorescent antibody assay), mild to moderate clinical signs (by observation, histology, and immunohistochemistry), and immune responses consistent with human infection (by flow cytometry and IgM ELISA). This model should give a better understanding of human CHIKV disease and allow for more realistic evaluations of mechanisms of pathogenesis, prophylaxis, and treatments. Author summary: In humans, CHIKV infections are mostly symptomatic, resulting in fever, viremia, and debilitating joint disease; viremia is present up to 13 days after the onset of fever and peaks at the onset of clinical signs. Previous studies in mice and nonhuman primates (NHPs) have often neglected the mosquito vector, leading to variable viremias and infection of tissues primarily at the sites of CHIKV injection (legs in mice, ankles or spleen/liver in NHPs). This is the first study to demonstrate systemic CHIKV infection caused by infected mosquito bites in humanized laboratory mice. Disease seen with this humanized mouse model mimics human clinical signs and symptoms, with signs of inflammation in muscle and joints due to viral replication. This humanized mouse model provides a basis for assessing human CHIKV pathogenesis, prophylaxis, and treatment, under natural conditions of infection. [ABSTRACT FROM AUTHOR]

(B) Infected, degenerate muscle fibrils from minimal (score 1) myositis at day 7 post mosquito bite, 40X magnification. (C) Infected, degenerate muscle fibrils from mild (score 2) myositis at day 14 post mosquito bite, 40X magnification. [Extracted from the article]

Background and objectives: Outpatient parenteral antimicrobial therapy (OPAT) for infections has been in use for nearly 40 years, and although it has been found safe and efficacious, its use has been studied primarily among otherwise healthy patients. We aimed to develop and evaluate an OPAT program for patients with cancer, particularly solid tumors. Methods: We implemented multiple quality improvement interventions between June 2018 and January 2020. We retrospectively and prospectively collected data on demographics, the completeness of infectious diseases (ID) physician consultation notes, rates of laboratory test result monitoring, ID clinic follow-up, and 30-day outcomes, including unplanned OPAT-related readmissions, OPAT-related emergency center visits, and deaths. Results: Completeness of ID provider notes improved from a baseline of 77 to 100% (p <.0001) for antimicrobial recommendations, 75 to 97% (p <.0001) for follow-up recommendations, and 19 to 98% (p <.0001) for laboratory test result monitoring recommendations. Completion of laboratory tests increased from a baseline rate of 24 to 56% (p =.027). Thirty-day unplanned OPAT-related readmission, ID clinic follow-up, 30-day emergency center visit, and death rates improved without reaching statistical significance. Conclusions: Sustained efforts, multiple interventions, and multidisciplinary engagement can improve laboratory test result monitoring among solid tumor patients discharged with OPAT. Although demonstrating a decrease in unplanned readmissions through institution of a formal OPAT program among patients with solid malignancies may be more difficult compared with the general population, the program may still result in improved safety. [ABSTRACT FROM AUTHOR]

Background: Zika virus (Flavivirus genus) is the first mosquito-borne virus known to cause high rates of microcephaly and abortion in humans. Typically, Zika virus causes a self-limiting, systemic illness; however, the current outbreak of Zika virus in the Americas has been associated with increased rates of fetal malformations and Guillain-Barré syndrome. Very few Zika virus isolates have been described in the literature, and live viruses are needed to perform studies of pathogenesis and to develop vaccines and treatments. Methodology/Clinical findings: We isolated Zika virus, strain FLR, directly from the serum of an individual infected in Barranquilla, Colombia (December, 2015). Here, we describe the patient’s clinical course and characterize strain FLR by its growth characteristics in mosquito and mammalian cells and its partial resistance to UV-inactivation. The full genome sequence of FLR was also analyzed (including the 3’ un-translated region), to determine its probable geographic origin, and to pinpoint structural differences from other Zika virus strains. Conclusions/Significance: We anticipate that the study of this low passage, clinical isolate of Zika virus, which is available for worldwide distribution, will help uncover the mechanisms of viral replication and host immune responses contributing to the varied and sometimes severe clinical presentations seen during the current epidemic in the Americas. [ABSTRACT FROM AUTHOR]