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Vibrio mimicus caused a seafood-associated outbreak in Florida, USA, in which 4 of 6 case-patients were hospitalized; 1 required intensive care for severe diarrhea. Strains were ctx-negative but carried genes for other virulence determinants (hemolysin, proteases, and types I-IV and VI secretion systems). Cholera toxin-negative bacterial strains can cause cholera-like disease.
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Cólera , Vibrio mimicus , Humanos , Cólera/epidemiología , Florida/epidemiología , Vibrio mimicus/genética , Brotes de Enfermedades , Alimentos MarinosRESUMEN
STUDY OBJECTIVE: To investigate risk of aortic aneurysm or dissection in patients using oral fluoroquinolones compared to those using macrolides in real-world clinical practice among a large US general population. DESIGN: Retrospective cohort study design. DATA SOURCE: MarketScan commercial and Medicare supplemental databases. PATIENTS: Adults patients with at least one prescription fill for fluoroquinolone or macrolide antibiotics. INTERVENTION: Fluoroquinolone or macrolide antibiotics. MEASUREMENTS AND MAIN RESULTS: The primary outcome was estimated incidence of aortic aneurysm or dissection associated with the use of fluoroquinolones compared with macrolides during a 60-day follow-up period in a 1:1 propensity score-matched cohort. We identified 3,174,620 patients (1,587,310 in each group) after 1:1 propensity score matching. Crude incidence of aortic aneurysm or dissection was 1.9 cases per 1000 person-years among fluoroquinolone users and 1.2 cases per 1000 person-years among macrolide users. In multivariable Cox regression, compared with macrolides, the use of fluoroquinolones was associated with an increased risk of aortic aneurysm or dissection (aHR: 1.34; 95% CI: 1.17-1.54). The association was primarily driven by a high incidence of aortic aneurysm cases (95.8%). Results of sensitivity (e.g., fluoroquinolone exposure ranging from 7 to 14 days (aHR: 1.47; 95% CI: 1.26-1.71)) and subgroup analyses (e.g., ciprofloxacin (aHR: 1.26; 95% CI: 1.07-1.49) and levofloxacin (aHR: 1.44; 95% CI: 1.19-1.52)) remained consistent with main findings. CONCLUSIONS: Fluoroquinolone use was associated with a 34% increased risk of aortic aneurysm or dissection compared with macrolide use among a general US population.
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Aneurisma de la Aorta , Disección Aórtica , Adulto , Humanos , Anciano , Estados Unidos , Fluoroquinolonas/efectos adversos , Estudios de Cohortes , Puntaje de Propensión , Estudios Retrospectivos , Disección Aórtica/inducido químicamente , Disección Aórtica/epidemiología , Medicare , Aneurisma de la Aorta/inducido químicamente , Aneurisma de la Aorta/epidemiología , Antibacterianos/efectos adversos , Macrólidos/efectos adversosRESUMEN
Background: Clinical trials initiated during emerging infectious disease outbreaks must quickly enroll participants to identify treatments to reduce morbidity and mortality. This may be at odds with enrolling a representative study population, especially when the population affected is undefined. Methods: We evaluated the utility of the Centers for Disease Control and Prevention's COVID-19-Associated Hospitalization Surveillance Network (COVID-NET), the COVID-19 Case Surveillance System (CCSS), and 2020 United States (US) Census data to determine demographic representation in the 4 stages of the Adaptive COVID-19 Treatment Trial (ACTT). We compared the cumulative proportion of participants by sex, race, ethnicity, and age enrolled at US ACTT sites, with respective 95% confidence intervals, to the reference data in forest plots. Results: US ACTT sites enrolled 3509 adults hospitalized with COVID-19. When compared with COVID-NET, ACTT enrolled a similar or higher proportion of Hispanic/Latino and White participants depending on the stage, and a similar proportion of African American participants in all stages. In contrast, ACTT enrolled a higher proportion of these groups when compared with US Census and CCSS. The proportion of participants aged ≥65 years was either similar or lower than COVID-NET and higher than CCSS and the US Census. The proportion of females enrolled in ACTT was lower than the proportion of females in the reference datasets. Conclusions: Although surveillance data of hospitalized cases may not be available early in an outbreak, they are a better comparator than US Census data and surveillance of all cases, which may not reflect the population affected and at higher risk of severe disease.
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BACKGROUND: Baricitinib and dexamethasone have randomised trials supporting their use for the treatment of patients with COVID-19. We assessed the combination of baricitinib plus remdesivir versus dexamethasone plus remdesivir in preventing progression to mechanical ventilation or death in hospitalised patients with COVID-19. METHODS: In this randomised, double-blind, double placebo-controlled trial, patients were enrolled at 67 trial sites in the USA (60 sites), South Korea (two sites), Mexico (two sites), Singapore (two sites), and Japan (one site). Hospitalised adults (≥18 years) with COVID-19 who required supplemental oxygen administered by low-flow (≤15 L/min), high-flow (>15 L/min), or non-invasive mechanical ventilation modalities who met the study eligibility criteria (male or non-pregnant female adults ≥18 years old with laboratory-confirmed SARS-CoV-2 infection) were enrolled in the study. Patients were randomly assigned (1:1) to receive either baricitinib, remdesivir, and placebo, or dexamethasone, remdesivir, and placebo using a permuted block design. Randomisation was stratified by study site and baseline ordinal score at enrolment. All patients received remdesivir (≤10 days) and either baricitinib (or matching oral placebo) for a maximum of 14 days or dexamethasone (or matching intravenous placebo) for a maximum of 10 days. The primary outcome was the difference in mechanical ventilation-free survival by day 29 between the two treatment groups in the modified intention-to-treat population. Safety analyses were done in the as-treated population, comprising all participants who received one dose of the study drug. The trial is registered with ClinicalTrials.gov, NCT04640168. FINDINGS: Between Dec 1, 2020, and April 13, 2021, 1047 patients were assessed for eligibility. 1010 patients were enrolled and randomly assigned, 516 (51%) to baricitinib plus remdesivir plus placebo and 494 (49%) to dexamethasone plus remdesivir plus placebo. The mean age of the patients was 58·3 years (SD 14·0) and 590 (58%) of 1010 patients were male. 588 (58%) of 1010 patients were White, 188 (19%) were Black, 70 (7%) were Asian, and 18 (2%) were American Indian or Alaska Native. 347 (34%) of 1010 patients were Hispanic or Latino. Mechanical ventilation-free survival by day 29 was similar between the study groups (Kaplan-Meier estimates of 87·0% [95% CI 83·7 to 89·6] in the baricitinib plus remdesivir plus placebo group and 87·6% [84·2 to 90·3] in the dexamethasone plus remdesivir plus placebo group; risk difference 0·6 [95% CI -3·6 to 4·8]; p=0·91). The odds ratio for improved status in the dexamethasone plus remdesivir plus placebo group compared with the baricitinib plus remdesivir plus placebo group was 1·01 (95% CI 0·80 to 1·27). At least one adverse event occurred in 149 (30%) of 503 patients in the baricitinib plus remdesivir plus placebo group and 179 (37%) of 482 patients in the dexamethasone plus remdesivir plus placebo group (risk difference 7·5% [1·6 to 13·3]; p=0·014). 21 (4%) of 503 patients in the baricitinib plus remdesivir plus placebo group had at least one treatment-related adverse event versus 49 (10%) of 482 patients in the dexamethasone plus remdesivir plus placebo group (risk difference 6·0% [2·8 to 9·3]; p=0·00041). Severe or life-threatening grade 3 or 4 adverse events occurred in 143 (28%) of 503 patients in the baricitinib plus remdesivir plus placebo group and 174 (36%) of 482 patients in the dexamethasone plus remdesivir plus placebo group (risk difference 7·7% [1·8 to 13·4]; p=0·012). INTERPRETATION: In hospitalised patients with COVID-19 requiring supplemental oxygen by low-flow, high-flow, or non-invasive ventilation, baricitinib plus remdesivir and dexamethasone plus remdesivir resulted in similar mechanical ventilation-free survival by day 29, but dexamethasone was associated with significantly more adverse events, treatment-related adverse events, and severe or life-threatening adverse events. A more individually tailored choice of immunomodulation now appears possible, where side-effect profile, ease of administration, cost, and patient comorbidities can all be considered. FUNDING: National Institute of Allergy and Infectious Diseases.
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Tratamiento Farmacológico de COVID-19 , Adolescente , Adulto , Azetidinas , Dexametasona , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oxígeno , Purinas , Pirazoles , SARS-CoV-2 , Sulfonamidas , Resultado del TratamientoRESUMEN
We isolated a novel coronavirus from a medical team member presenting with fever and malaise after travel to Haiti. The virus showed 99.4% similarity with a recombinant canine coronavirus recently identified in a pneumonia patient in Malaysia, suggesting that infection with this virus and/or recombinant variants occurs in multiple locations.
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COVID-19 , Coronavirus Canino , Animales , Perros , Haití , Humanos , SARS-CoV-2/genética , ViajeRESUMEN
BACKGROUND: Functional impairment of interferon, a natural antiviral component of the immune system, is associated with the pathogenesis and severity of COVID-19. We aimed to compare the efficacy of interferon beta-1a in combination with remdesivir compared with remdesivir alone in hospitalised patients with COVID-19. METHODS: We did a double-blind, randomised, placebo-controlled trial at 63 hospitals across five countries (Japan, Mexico, Singapore, South Korea, and the USA). Eligible patients were hospitalised adults (aged ≥18 years) with SARS-CoV-2 infection, as confirmed by a positive RT-PCR test, and who met one of the following criteria suggestive of lower respiratory tract infection: the presence of radiographic infiltrates on imaging, a peripheral oxygen saturation on room air of 94% or less, or requiring supplemental oxygen. Patients were excluded if they had either an alanine aminotransferase or an aspartate aminotransferase concentration more than five times the upper limit of normal; had impaired renal function; were allergic to the study product; were pregnant or breast feeding; were already on mechanical ventilation; or were anticipating discharge from the hospital or transfer to another hospital within 72 h of enrolment. Patients were randomly assigned (1:1) to receive intravenous remdesivir as a 200 mg loading dose on day 1 followed by a 100 mg maintenance dose administered daily for up to 9 days and up to four doses of either 44 µg interferon beta-1a (interferon beta-1a group plus remdesivir group) or placebo (placebo plus remdesivir group) administered subcutaneously every other day. Randomisation was stratified by study site and disease severity at enrolment. Patients, investigators, and site staff were masked to interferon beta-1a and placebo treatment; remdesivir treatment was given to all patients without masking. The primary outcome was time to recovery, defined as the first day that a patient attained a category 1, 2, or 3 score on the eight-category ordinal scale within 28 days, assessed in the modified intention-to-treat population, defined as all randomised patients who were classified according to actual clinical severity. Safety was assessed in the as-treated population, defined as all patients who received at least one dose of the assigned treatment. This trial is registered with ClinicalTrials.gov, NCT04492475. FINDINGS: Between Aug 5, 2020, and Nov 11, 2020, 969 patients were enrolled and randomly assigned to the interferon beta-1a plus remdesivir group (n=487) or to the placebo plus remdesivir group (n=482). The mean duration of symptoms before enrolment was 8·7 days (SD 4·4) in the interferon beta-1a plus remdesivir group and 8·5 days (SD 4·3) days in the placebo plus remdesivir group. Patients in both groups had a time to recovery of 5 days (95% CI not estimable) (rate ratio of interferon beta-1a plus remdesivir group vs placebo plus remdesivir 0·99 [95% CI 0·87-1·13]; p=0·88). The Kaplan-Meier estimate of mortality at 28 days was 5% (95% CI 3-7%) in the interferon beta-1a plus remdesivir group and 3% (2-6%) in the placebo plus remdesivir group (hazard ratio 1·33 [95% CI 0·69-2·55]; p=0·39). Patients who did not require high-flow oxygen at baseline were more likely to have at least one related adverse event in the interferon beta-1a plus remdesivir group (33 [7%] of 442 patients) than in the placebo plus remdesivir group (15 [3%] of 435). In patients who required high-flow oxygen at baseline, 24 (69%) of 35 had an adverse event and 21 (60%) had a serious adverse event in the interferon beta-1a plus remdesivir group compared with 13 (39%) of 33 who had an adverse event and eight (24%) who had a serious adverse event in the placebo plus remdesivir group. INTERPRETATION: Interferon beta-1a plus remdesivir was not superior to remdesivir alone in hospitalised patients with COVID-19 pneumonia. Patients who required high-flow oxygen at baseline had worse outcomes after treatment with interferon beta-1a compared with those given placebo. FUNDING: The National Institute of Allergy and Infectious Diseases (USA).
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Adenosina Monofosfato/análogos & derivados , Alanina/análogos & derivados , Antivirales/uso terapéutico , Tratamiento Farmacológico de COVID-19 , Interferón beta-1a/uso terapéutico , Adenosina Monofosfato/uso terapéutico , Adulto , Anciano , Alanina/uso terapéutico , Método Doble Ciego , Femenino , Humanos , Japón , Masculino , México , Persona de Mediana Edad , Oxígeno , Saturación de Oxígeno , República de Corea , SARS-CoV-2 , Singapur , Resultado del Tratamiento , Estados UnidosRESUMEN
BACKGROUND: NDM-producing Enterobacteriaceae are a major clinical concern worldwide. We characterized NDM-positive pathogens isolated from patients and assessed the dissemination patterns of the bla NDM genes in a hospital setting. METHODS: Eleven NDM-positive Enterobacteriaceae (three Enterobacter hormaechei, six Klebsiella pneumoniae and two Escherichia coli) were isolated from nine patients over a 1 year period. Antimicrobial susceptibility was assessed by MICs. A combination of short- and long-read WGS was used for genome analysis. Clinical treatment history of patients was linked with genetic features of individual isolates to investigate the dissemination patterns of the bla NDM genes and NDM-positive strains. RESULTS: bla NDM in clonal K. pneumoniae were transmitted between two patients. In other instances, an identical IncC plasmid encoding NDM-1 was transmitted between E. coli and K. pneumoniae isolated from the same patient, and an IncX3 plasmid, carrying bla NDM-1 or bla NDM-5, was harboured in non-clonal E. hormaechei. Varying patterns of IS elements were identified as a critical transmission mechanism in association with bla NDM genes. CONCLUSIONS: Multiple transmission patterns were identified in hospitalized patients, including dissemination of clonal bacterial strains carrying resistance genes and horizontal transfer of resistance genes among divergent bacterial strains. Controlling spread of NDM is complex: while attention to standard infection control practices is critically important, this needs to be matched by aggressive efforts to limit unnecessary antimicrobial use, to minimize the selection for and risk of transfer of 'high mobility' resistance genes among Enterobacteriaceae.
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BACKGROUND: Severe coronavirus disease 2019 (Covid-19) is associated with dysregulated inflammation. The effects of combination treatment with baricitinib, a Janus kinase inhibitor, plus remdesivir are not known. METHODS: We conducted a double-blind, randomized, placebo-controlled trial evaluating baricitinib plus remdesivir in hospitalized adults with Covid-19. All the patients received remdesivir (≤10 days) and either baricitinib (≤14 days) or placebo (control). The primary outcome was the time to recovery. The key secondary outcome was clinical status at day 15. RESULTS: A total of 1033 patients underwent randomization (with 515 assigned to combination treatment and 518 to control). Patients receiving baricitinib had a median time to recovery of 7 days (95% confidence interval [CI], 6 to 8), as compared with 8 days (95% CI, 7 to 9) with control (rate ratio for recovery, 1.16; 95% CI, 1.01 to 1.32; P = 0.03), and a 30% higher odds of improvement in clinical status at day 15 (odds ratio, 1.3; 95% CI, 1.0 to 1.6). Patients receiving high-flow oxygen or noninvasive ventilation at enrollment had a time to recovery of 10 days with combination treatment and 18 days with control (rate ratio for recovery, 1.51; 95% CI, 1.10 to 2.08). The 28-day mortality was 5.1% in the combination group and 7.8% in the control group (hazard ratio for death, 0.65; 95% CI, 0.39 to 1.09). Serious adverse events were less frequent in the combination group than in the control group (16.0% vs. 21.0%; difference, -5.0 percentage points; 95% CI, -9.8 to -0.3; P = 0.03), as were new infections (5.9% vs. 11.2%; difference, -5.3 percentage points; 95% CI, -8.7 to -1.9; P = 0.003). CONCLUSIONS: Baricitinib plus remdesivir was superior to remdesivir alone in reducing recovery time and accelerating improvement in clinical status among patients with Covid-19, notably among those receiving high-flow oxygen or noninvasive ventilation. The combination was associated with fewer serious adverse events. (Funded by the National Institute of Allergy and Infectious Diseases; ClinicalTrials.gov number, NCT04401579.).
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Adenosina Monofosfato/análogos & derivados , Alanina/análogos & derivados , Antivirales/uso terapéutico , Azetidinas/uso terapéutico , Tratamiento Farmacológico de COVID-19 , Purinas/uso terapéutico , Pirazoles/uso terapéutico , Sulfonamidas/uso terapéutico , Adenosina Monofosfato/efectos adversos , Adenosina Monofosfato/uso terapéutico , Adulto , Anciano , Alanina/efectos adversos , Alanina/uso terapéutico , Antivirales/efectos adversos , Azetidinas/efectos adversos , COVID-19/mortalidad , COVID-19/terapia , Método Doble Ciego , Quimioterapia Combinada , Femenino , Mortalidad Hospitalaria , Hospitalización , Humanos , Inhibidores de las Cinasas Janus/efectos adversos , Inhibidores de las Cinasas Janus/uso terapéutico , Masculino , Persona de Mediana Edad , Terapia por Inhalación de Oxígeno , Purinas/efectos adversos , Pirazoles/efectos adversos , Respiración Artificial , Sulfonamidas/efectos adversos , Resultado del TratamientoRESUMEN
This review will briefly examine the clinical presentation and important immunology of viral pneumonia with a focus on severe acute respiratory syndrome coronavirus 2 (coronavirus disease 2019). DATA SOURCES STUDY SELECTION DATA EXTRACTION AND DATA SYNTHESIS: The most relevant, original and review literature were assessed for inclusion in this review. Sources included the Centers for Disease Control and Prevention, World Health Organization, and PubMed. CONCLUSIONS: Pneumonia is a leading cause of hospitalization and death worldwide, with viral etiologies being very common. Given the rapidly emerging pandemic associated with the novel severe acute respiratory syndrome coronavirus 2 causing coronavirus disease 2019, it is important to review the clinical presentation and immunologic changes associated with viral pneumonia. Symptoms of viral pneumonia include common respiratory tract infection symptoms of cough, fever, and shortness of breath. Immunologic changes include up-regulation of airway pro-inflammatory cytokines and pathogen- and damage-associated molecular patterns contributing to cytokine and genomic changes. Coronavirus disease 2019 clinical presentation is typical of viral pneumonia with an increased prevalence of early pulmonary infiltrates and lymphopenia. Principles of early coronavirus disease 2019 management and isolation as well as potential therapeutic approaches to the emerging pandemic are discussed.
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Coronavirus disease 2019, first reported in China in late 2019, has quickly spread across the world. The outbreak was declared a pandemic by the World Health Organization on March 11, 2020. Here, we describe our initial efforts at the University of Florida Health for processing of large numbers of tests, streamlining data collection, and reporting data for optimizing testing capabilities and superior clinical management. Specifically, we discuss clinical and pathology informatics workflows and informatics instruments which we designed to meet the unique challenges of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) testing. We hope these results benefit institutions preparing to implement SARS-CoV-2 testing.
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In 2018, the Food and Drug Administration/Centers for Disease Control and Prevention revised protocols for surveillance sampling and cultures of duodenoscopes. We describe the recovery of the mold Curvularia from a duodenoscope processed according to the manufacturer's instructions using this revised sampling process. To our knowledge, this is the first time a mold has been recovered from a duodenoscope after following the Food and Drug Administration/Centers for Disease Control and Prevention protocol. This suggests that manufacturer's recommendation for scope reprocessing may be insufficient to adequately remove mold from these scopes.
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Infección Hospitalaria/parasitología , Curvularia/aislamiento & purificación , Desinfección/métodos , Duodenoscopios/parasitología , Micosis/parasitología , Desinfección/normas , Contaminación de Equipos , Equipo Reutilizado , HumanosRESUMEN
Four patients with adult-onset, disseminated mycobacterial infection had 5' UTR mutations in IKBKG without clear physical stigmata of NEMO deficiency. These mutations caused decreased levels of NEMO protein and Toll-like receptor driven cytokine production. Three patients died from disseminated disease. These mutations may be missed by whole exome sequencing.
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Displasia Ectodérmica/complicaciones , Enfermedades Genéticas Ligadas al Cromosoma X/complicaciones , Quinasa I-kappa B/genética , Síndromes de Inmunodeficiencia/complicaciones , Infecciones por Mycobacterium/genética , Sitios de Empalme de ARN , Adulto , Displasia Ectodérmica/microbiología , Enfermedades Genéticas Ligadas al Cromosoma X/microbiología , Humanos , Síndromes de Inmunodeficiencia/microbiología , Masculino , Mutación , Infecciones por Mycobacterium/sangre , Infecciones por Mycobacterium/mortalidad , Enfermedades de Inmunodeficiencia Primaria , Transducción de Señal , Piel/microbiología , Piel/patologíaAsunto(s)
Programas de Optimización del Uso de los Antimicrobianos/métodos , Enfermedades Transmisibles/tratamiento farmacológico , Farmacorresistencia Bacteriana Múltiple , Médicos , Programas de Optimización del Uso de los Antimicrobianos/legislación & jurisprudencia , Programas de Optimización del Uso de los Antimicrobianos/organización & administración , Centers for Disease Control and Prevention, U.S. , Control de Enfermedades Transmisibles/métodos , Humanos , Sociedades Médicas , Especialización , Estados UnidosRESUMEN
The majority of dengue fever cases reported in the United States recently have been imported. We isolated dengue virus type 2 (DENV-2) from a North-Central Florida resident with locally acquired dengue fever in May 2016. This is the first evidence of autochthonous transmission of the virus in north-central Florida.
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Zika virus and dengue virus serotype 2 were isolated from a patient with travel to Haiti who developed fever, rash, arthralgias, and conjunctivitis. The infecting Zika virus was related to Venezuelan and Brazilian strains but evolved along a lineage originating from strains isolated in 2014 in the same region of Haiti.
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Coinfección , Virus del Dengue/genética , Dengue/diagnóstico , Dengue/virología , Viaje , Infección por el Virus Zika/diagnóstico , Infección por el Virus Zika/virología , Virus Zika/genética , Adulto , Virus del Dengue/clasificación , Femenino , Haití , Humanos , Filogenia , Reacción en Cadena de la Polimerasa , ARN Viral , Serotipificación , Evaluación de Síntomas , Virus Zika/clasificaciónRESUMEN
INTRODUCTION: Zikavirus (ZIKV) and Chikungunyavirus (CHIKV) can share the same mosquito vector, and co-infections by these viruses can occur in humans. While infections with these viruses share commonalities, CHIKV is unique in causing arthritis and arthralgias that may persist for a year or more. These infections are commonly diagnosed by RT-PCR-based methods during the acute phase of infection. Even with the high specificity and sensitivity characteristic of PCR, false negatives can occur, highlighting the need for additional diagnostic methods for confirmation. CASE PRESENTATION: On her return to the USA, a traveller to Colombia, South America developed an illness consistent with Zika, Chikungunya and/or Dengue. RT-PCR of her samples was positive only for ZIKV. However, arthralgias persisted for months, raising concerns about co-infection with CHIKV or Mayaro viruses. Cell cultures inoculated with her original clinical samples demonstrated two types of cytopathic effects, and both ZIKV and CHIKV were identified in the supernatants. On phylogenetic analyses, both viruses were found to be related to strains found in Colombia. CONCLUSION: These findings highlight the need to consider CHIKV co-infection in patients with prolonged rheumatological symptoms after diagnosis with ZIKV, and the usefulness of cell culture as an amplification step for low-viremia blood and other samples.
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Influenza A(H3N2) strains isolated during 2014-15 in Alachua County, Florida, USA, belonged to hemagglutinin gene clade 3C.2a. High rates of influenza-like illness and confirmed influenza cases in children were associated with a decrease in estimated vaccine effectiveness. Illnesses were milder than in 2013-14; severe cases were concentrated in elderly patients with underlying diseases.
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Hemaglutininas/genética , Subtipo H3N2 del Virus de la Influenza A/genética , Gripe Humana/virología , Adolescente , Niño , Preescolar , Florida , Pruebas de Inhibición de Hemaglutinación/métodos , Humanos , Lactante , Recién Nacido , Subtipo H3N2 del Virus de la Influenza A/inmunología , Vacunas contra la Influenza/inmunología , Gripe Humana/inmunologíaRESUMEN
Avibactam is a novel ß-lactamase inhibitor with affinity for Klebsiella pneumoniae carbapenemases (KPCs). In combination with ceftazidime, the agent demonstrates activity against KPC-producing K. pneumoniae (KPC-Kp). KPC-Kp strains are genetically diverse and harbor multiple resistance determinants, including defects in outer membrane proteins and extended-spectrum ß-lactamases (ESBLs). Mutations in porin gene ompK36 confer high-level carbapenem resistance to KPC-Kp strains. Whether specific mechanisms of antimicrobial resistance also influence the activity of ceftazidime-avibactam is unknown. We defined the effects of ceftazidime-avibactam against 72 KPC-Kp strains with diverse mechanisms of resistance, including various combinations of KPC subtypes and ESBL and ompK36 mutations. Ceftazidime MICs ranged from 64 to 4,096 µg/ml and were lowered by a median of 512-fold with the addition of avibactam. All strains exhibited ceftazidime-avibactam MICs at or below the CLSI breakpoint for ceftazidime (≤4 µg/ml; range, 0.25 to 4). However, the MICs were within two 2-fold dilutions of the CLSI breakpoint against 24% of the strains, and those strains would be classified as nonsusceptible to ceftazidime by EUCAST criteria (MIC > 1 µg/ml). Median ceftazidime-avibactam MICs were higher against KPC-3 than KPC-2 variants (P = 0.02). Among KPC-2-Kp strains, the presence of both ESBL and porin mutations was associated with higher drug MICs compared to those seen with either factor alone (P = 0.003 and P = 0.02, respectively). In conclusion, ceftazidime-avibactam displays activity against genetically diverse KPC-Kp strains. Strains with higher-level drug MICs provide a reason for caution. Judicious use of ceftazidime-avibactam alone or in combination with other agents will be important to prevent the emergence of resistance.
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Antibacterianos/farmacología , Compuestos de Azabiciclo/farmacología , Proteínas Bacterianas/metabolismo , Ceftazidima/farmacología , Klebsiella pneumoniae/efectos de los fármacos , Klebsiella pneumoniae/enzimología , Porinas/genética , Inhibidores de beta-Lactamasas/farmacología , beta-Lactamasas/metabolismo , Combinación de Medicamentos , Pruebas de Sensibilidad Microbiana , Mutación/genéticaRESUMEN
Despite a regional decline in influenza A(H1N1)pdm09 virus infections during 2013-14, cases at a Florida hospital were more severe than those during 2009-10. Examined strains had a hemagglutinin polymorphism associated with enhanced binding to lower respiratory tract receptors. Genetic changes in this virus must be monitored to predict the effect of future pandemic viruses.
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Variación Genética , Subtipo H1N1 del Virus de la Influenza A/genética , Gripe Humana/epidemiología , Gripe Humana/virología , Estaciones del Año , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Comorbilidad , Femenino , Florida/epidemiología , Historia del Siglo XXI , Humanos , Gripe Humana/historia , Gripe Humana/patología , Pulmón/patología , Pulmón/virología , Masculino , Persona de Mediana Edad , Mortalidad , Adulto JovenRESUMEN
The cell tropism of human noroviruses and the development of an in vitro infection model remain elusive. Although susceptibility to individual human norovirus strains correlates with an individual's histo-blood group antigen (HBGA) profile, the biological basis of this restriction is unknown. We demonstrate that human and mouse noroviruses infected B cells in vitro and likely in vivo. Human norovirus infection of B cells required the presence of HBGA-expressing enteric bacteria. Furthermore, mouse norovirus replication was reduced in vivo when the intestinal microbiota was depleted by means of oral antibiotic administration. Thus, we have identified B cells as a cellular target of noroviruses and enteric bacteria as a stimulatory factor for norovirus infection, leading to the development of an in vitro infection model for human noroviruses.