Phylogenetic and phenotypic characterization of Burkholderia pseudomallei isolates from Ghana reveals a novel sequence type and common phenotypes.

Melioidosis is a potentially severe disease caused by the gram-negative soil-dwelling bacterium called Burkholderia pseudomallei. The true breadth of the distribution of this tropical pathogen is starting to emerge with environmental and clinical isolates frequently characterized in new countries and regions. Even so, isolates, clinical cases, and genetic data from the continent of Africa remain scant. We previously confirmed the presence of B. pseudomallei in the environment of Ghana, unmasking a new area of endemicity for this pathogen. Here, we describe the genetic characteristics of isolates obtained from that environmental survey. Twenty-one isolates were subjected to whole genome sequencing and found to represent three discrete sequence types (ST), one of which was novel, and designated ST2058. Phylogenetic analysis places this novel isolate within a B. pseudomallei clade that includes genomes derived from the Americas, although it is closely related to a sub-clade that includes isolates from Africa. Importantly, phenotypic characterization demonstrates common features including API 20NE profiles and B. pseudomallei CPS to support existing diagnostics, and susceptibility to standard of care antibiotics often used in the clinical management of melioidosis. These findings add to our knowledge about the presence and distribution of B. pseudomallei in Africa and represent the first published genomes out of Ghana.

Immune and behavioral correlates of protection against symptomatic post-vaccination SARS-CoV-2 infection.

Introduction: We sought to determine pre-infection correlates of protection against SARS-CoV-2 post-vaccine inzfections (PVI) acquired during the first Omicron wave in the United States. Methods: Serum and saliva samples from 176 vaccinated adults were collected from October to December of 2021, immediately before the Omicron wave, and assessed for SARS-CoV-2 Spike-specific IgG and IgA binding antibodies (bAb). Sera were also assessed for bAb using commercial assays, and for neutralization activity against several SARS-CoV-2 variants. PVI duration and severity, as well as risk and precautionary behaviors, were assessed by questionnaires. Results: Serum anti-Spike IgG levels assessed by research assay, neutralization titers against Omicron subvariants, and low home risk scores correlated with protection against PVIs after multivariable regression analysis. Commercial assays did not perform as well as research assay, likely due to their lower dynamic range. Discussion: In the 32 participants that developed PVI, anti-Spike IgG bAbs correlated with lower disease severity and shorter duration of illness.

Genomic Surveillance of Rabies Virus in Georgian Canines.

Rabies is a fatal zoonosis that is considered a re-emerging infectious disease. Although rabies remains endemic in canines throughout much of the world, vaccination programs have essentially eliminated dog rabies in the Americas and much of Europe. However, despite the goal of eliminating dog rabies in the European Union by 2020, sporadic cases of dog rabies still occur in Eastern Europe, including Georgia. To assess the genetic diversity of the strains recently circulating in Georgia, we sequenced seventy-eight RABV-positive samples from the brain tissues of rabid dogs and jackals using Illumina short-read sequencing of total RNA shotgun libraries. Seventy-seven RABV genomes were successfully assembled and annotated, with seventy-four of them reaching the coding-complete status. Phylogenetic analyses of the nucleoprotein (N) and attachment glycoprotein (G) genes placed all the assembled genomes into the Cosmopolitan clade, consistent with the Georgian origin of the samples. An amino acid alignment of the G glycoprotein ectodomain identified twelve different sequences for this domain among the samples. Only one of the ectodomain groups contained a residue change in an antigenic site, an R264H change in the G5 antigenic site. Three isolates were cultured, and these were found to be efficiently neutralized by the human monoclonal antibody A6. Overall, our data show that recently circulating RABV isolates from Georgian canines are predominantly closely related phylogroup I viruses of the Cosmopolitan clade. Current human rabies vaccines should offer protection against infection by Georgian canine RABVs. The genomes have been deposited in GenBank (accessions: OQ603609-OQ603685).

A Recombinant Chimeric Cedar Virus-Based Surrogate Neutralization Assay Platform for Pathogenic Henipaviruses.

The henipaviruses, Nipah virus (NiV), and Hendra virus (HeV) can cause fatal diseases in humans and animals, whereas Cedar virus is a nonpathogenic henipavirus. Here, using a recombinant Cedar virus (rCedV) reverse genetics platform, the fusion (F) and attachment (G) glycoprotein genes of rCedV were replaced with those of NiV-Bangladesh (NiV-B) or HeV, generating replication-competent chimeric viruses (rCedV-NiV-B and rCedV-HeV), both with and without green fluorescent protein (GFP) or luciferase protein genes. The rCedV chimeras induced a Type I interferon response and utilized only ephrin-B2 and ephrin-B3 as entry receptors compared to rCedV. The neutralizing potencies of well-characterized cross-reactive NiV/HeV F and G specific monoclonal antibodies against rCedV-NiV-B-GFP and rCedV-HeV-GFP highly correlated with measurements obtained using authentic NiV-B and HeV when tested in parallel by plaque reduction neutralization tests (PRNT). A rapid, high-throughput, and quantitative fluorescence reduction neutralization test (FRNT) using the GFP-encoding chimeras was established, and monoclonal antibody neutralization data derived by FRNT highly correlated with data derived by PRNT. The FRNT assay could also measure serum neutralization titers from henipavirus G glycoprotein immunized animals. These rCedV chimeras are an authentic henipavirus-based surrogate neutralization assay that is rapid, cost-effective, and can be utilized outside high containment.

Establishment of SARS-CoV-2 genomic surveillance within the Military Health System during 1 March-31 December 2020.

This report describes SARS-CoV-2 genomic surveillance conducted by the Department of Defense (DoD) Global Emerging Infections Surveillance Branch and the Next-Generation Sequencing and Bioinformatics Consortium (NGSBC) in response to the COVID-19 pandemic. Samples and sequence data were from SARS-CoV-2 infections occurring among Military Health System (MHS) beneficiaries from 1 March to 31 December 2020. There were 1,366 MHS samples sequenced from 10 countries, 36 U.S states or territories, and 5 Geographic Combatant Commands, representing approximately 2% of DoD cases in 2020. Genomes from these samples were compared with other public sequences; observed trends were similar to those of Centers for Disease Control and Prevention national surveillance in the U.S. with B.1, B.1.2, and other sub-lineages comprising the dominant variants of SARS-CoV-2. Sequence data were used to monitor transmission dynamics on U.S. Navy ships and at military training centers and installations. As new variants emerge, DoD medical and public health practitioners should maximize the use of genomic surveillance resources within DoD to inform force health protection measures.

SARS-CoV-2 Infections in Vaccinated and Unvaccinated Populations in Camp Lemonnier, Djibouti, from April 2020 to January 2022.

The global pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has highlighted the disparity between developed and developing countries for infectious disease surveillance and the sequencing of pathogen genomes. The majority of SARS-CoV-2 sequences published are from Europe, North America, and Asia. Between April 2020 and January 2022, 795 SARS-CoV-2-positive nares swabs from individuals in the U.S. Navy installation Camp Lemonnier, Djibouti, were collected, sequenced, and analyzed. In this study, we described the results of genomic sequencing and analysis for 589 samples, the first published viral sequences for Djibouti, including 196 cases of vaccine breakthrough infections. This study contributes to the knowledge base of circulating SARS-CoV-2 lineages in the under-sampled country of Djibouti, where only 716 total genome sequences are available at time of publication. Our analysis resulted in the detection of circulating variants of concern, mutations of interest in lineages in which those mutations are not common, and emerging spike mutations.

SARS-CoV-2 Outbreak Dynamics in an Isolated US Military Recruit Training Center With Rigorous Prevention Measures.

BACKGROUND: Marine recruits training at Parris Island experienced an unexpectedly high rate of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, despite preventive measures including a supervised, 2-week, pre-entry quarantine. We characterize SARS-CoV-2 transmission in this cohort. METHODS: Between May and November 2020, we monitored 2,469 unvaccinated, mostly male, Marine recruits prospectively during basic training. If participants tested negative for SARS-CoV-2 by quantitative polymerase chain reaction (qPCR) at the end of quarantine, they were transferred to the training site in segregated companies and underwent biweekly testing for 6 weeks. We assessed the effects of coronavirus disease 2019 (COVID-19) prevention measures on other respiratory infections with passive surveillance data, performed phylogenetic analysis, and modeled transmission dynamics and testing regimens. RESULTS: Preventive measures were associated with drastically lower rates of other respiratory illnesses. However, among the trainees, 1,107 (44.8%) tested SARS-CoV-2-positive, with either mild or no symptoms. Phylogenetic analysis of viral genomes from 580 participants revealed that all cases but one were linked to five independent introductions, each characterized by accumulation of mutations across and within companies, and similar viral isolates in individuals from the same company. Variation in company transmission rates (mean reproduction number R 0 ; 5.5 [95% confidence interval [CI], 5.0, 6.1]) could be accounted for by multiple initial cases within a company and superspreader events. Simulations indicate that frequent rapid-report testing with case isolation may minimize outbreaks. CONCLUSIONS: Transmission of wild-type SARS-CoV-2 among Marine recruits was approximately twice that seen in the community. Insights from SARS-CoV-2 outbreak dynamics and mutations spread in a remote, congregate setting may inform effective mitigation strategies.

Genomic and virologic characterization of samples from a shipboard outbreak of COVID-19 reveals distinct variants within limited temporospatial parameters.

Early in the pandemic, in March of 2020, an outbreak of COVID-19 occurred aboard the aircraft carrier USS Theodore Roosevelt (CVN-71), during deployment in the Western Pacific. Out of the crew of 4,779 personnel, 1,331 service members were suspected or confirmed to be infected with SARS-CoV-2. The demographic, epidemiologic, and laboratory findings of service members from subsequent investigations have characterized the outbreak as widespread transmission of virus with relatively mild symptoms and asymptomatic infection among mostly young healthy adults. At the time, there was no available vaccination against COVID-19 and there was very limited knowledge regarding SARS-CoV-2 mutation, dispersal, and transmission patterns among service members in a shipboard environment. Since that time, other shipboard outbreaks from which data can be extracted have occurred, but these later shipboard outbreaks have occurred largely in settings where the majority of the crew were vaccinated, thereby limiting spread of the virus, shortening duration of the outbreaks, and minimizing evolution of the virus within those close quarters settings. On the other hand, since the outbreak on the CVN-71 occurred prior to widespread vaccination, it continued over the course of roughly two months, infecting more than 25% of the crew. In order to better understand genetic variability and potential transmission dynamics of COVID-19 in a shipboard environment of immunologically naïve, healthy individuals, we performed whole-genome sequencing and virus culture from eighteen COVID-19-positive swabs collected over the course of one week. Using the unique variants identified in those genomes, we detected seven discrete groups of individuals within the population aboard CVN-71 infected with viruses of distinct genomic signature. This is in stark contrast to a recent outbreak aboard another U.S. Navy ship with >98% vaccinated crew after a port visit in Reykjavik, Iceland, where the outbreak lasted only approximately 2 weeks and the virus was clonal. Taken together, these results demonstrate the utility of sequencing from complex clinical samples for molecular epidemiology and they also suggest that a high rate of vaccination among a population in close communities may greatly reduce spread, thereby restricting evolution of the virus.

Prospective Assessment of Symptoms to Evaluate Asymptomatic SARS-CoV-2 Infections in a Cohort of Health Care Workers.

BACKGROUND: The frequency of asymptomatic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections is unclear and may be influenced by how symptoms are evaluated. In this study, we sought to determine the frequency of asymptomatic SARS-CoV-2 infections in a prospective cohort of health care workers (HCWs). METHODS: A prospective cohort of HCWs, confirmed negative for SARS-CoV-2 exposure upon enrollment, were evaluated for SARS-CoV-2 infection by monthly analysis of SARS-CoV-2 antibodies as well as referral for polymerase chain reaction testing whenever they exhibited symptoms of coronavirus disease 2019 (COVID-19). Participants completed the standardized and validated FLU-PRO Plus symptom questionnaire scoring viral respiratory disease symptom intensity and frequency at least twice monthly during baseline periods of health and each day they had any symptoms that were different from their baseline. RESULTS: Two hundred sixty-three participants were enrolled between August 25 and December 31, 2020. Through February 28, 2021, 12 participants were diagnosed with SARS-CoV-2 infection. Symptom analysis demonstrated that all 12 had at least mild symptoms of COVID-19, compared with baseline health, near or at time of infection. CONCLUSIONS: These results suggest that asymptomatic SARS-CoV-2 infection in unvaccinated, immunocompetent adults is less common than previously reported. While infectious inoculum doses and patient factors may have played a role in the clinical manifestations of SARS-CoV-2 infections in this cohort, we suspect that the high rate of symptomatic disease was due primarily to participant attentiveness to symptoms and collection of symptoms in a standardized, prospective fashion. These results have implications for studies that estimate SARS-CoV-2 infection prevalence and for public health measures to control the spread of this virus.

Immunological and Genetic Investigation of SARS-CoV-2 Reinfection in an Otherwise Healthy, Young Marine Recruit.

We used epidemiologic and viral genetic information to identify a case of likely reinfection in an otherwise healthy, young Marine recruit enrolled in the prospective, longitudinal COVID-19 Health Action Response for Marines (CHARM) study, and we paired these findings with serological studies. This participant had a positive RT-PCR to SARS-CoV-2 upon routine sampling on study day 7, although he was asymptomatic at that time. He cleared the infection within seven days. On study day 46, he had developed symptoms consistent with COVID-19 and tested positive by RT-PCR for SARS-CoV-2 again. Viral whole genome sequencing was conducted from nares swabs at multiple time points. The day 7 sample was determined to be lineage B.1.340, whereas both the day 46 and day 49 samples were B.1.1. The first positive result for anti-SARS-CoV-2 IgM serology was collected on day 49 and for IgG on day 91. This case appears most consistent with a reinfection event. Our investigation into this case is unique in that we compared sequence data from more than just paired specimens, and we also assayed for immune response after both the initial infection and the later reinfection. These data demonstrate that individuals who have experienced an infection with SARS-CoV-2 may fail to generate effective or long-lasting immunity, similar to endemic human beta coronaviruses.

Genomic and Virological Characterization of SARS-CoV-2 Variants in a Subset of Unvaccinated and Vaccinated U.S. Military Personnel.

The emergence of SARS-CoV-2 variants complicates efforts to control the COVID-19 pandemic. Increasing genomic surveillance of SARS-CoV-2 is imperative for early detection of emerging variants, to trace the movement of variants, and to monitor effectiveness of countermeasures. Additionally, determining the amount of viable virus present in clinical samples is helpful to better understand the impact these variants have on viral shedding. In this study, we analyzed nasal swab samples collected between March 2020 and early November 2021 from a cohort of United States (U.S.) military personnel and healthcare system beneficiaries stationed worldwide as a part of the Defense Health Agency's (DHA) Global Emerging Infections Surveillance (GEIS) program. SARS-CoV-2 quantitative real time reverse-transcription PCR (qRT-PCR) positive samples were characterized by next-generation sequencing and a subset was analyzed for isolation and quantification of viable virus. Not surprisingly, we found that the Delta variant is the predominant strain circulating among U.S. military personnel beginning in July 2021 and primarily represents cases of vaccine breakthrough infections (VBIs). Among VBIs, we found a 50-fold increase in viable virus in nasal swab samples from Delta variant cases when compared to cases involving other variants. Notably, we found a 40-fold increase in viable virus in nasal swab samples from VBIs involving Delta as compared to unvaccinated personnel infected with other variants prior to the availability of approved vaccines. This study provides important insight about the genomic and virological characterization of SARS-CoV-2 isolates from a unique study population with a global presence.

Phage Therapy for Limb-threatening Prosthetic Knee Klebsiella pneumoniae Infection: Case Report and In Vitro Characterization of Anti-biofilm Activity.

BACKGROUND: Prosthetic joint infection (PJI) is a potentially limb-threatening complication of total knee arthroplasty. Phage therapy is a promising strategy to manage such infections including those involving antibiotic-resistant microbes, and to target microbial biofilms. Experience with phage therapy for infections associated with retained hardware is limited. A 62-year-old diabetic man with a history of right total knee arthroplasty 11 years prior who had suffered multiple episodes of prosthetic knee infection despite numerous surgeries and prolonged courses of antibiotics, with progressive clinical worsening and development of severe allergies to antibiotics, had been offered limb amputation for persistent right prosthetic knee infection due to Klebsiella pneumoniae complex. Intravenous phage therapy was initiated as a limb-salvaging intervention. METHODS: The patient received 40 intravenous doses of a single phage (KpJH46Φ2) targeting his bacterial isolate, alongside continued minocycline (which he had been receiving when he developed increasing pain, swelling, and erythema prior to initiation of phage therapy). Serial cytokine and biomarker measurements were performed before, during, and after treatment. The in vitro anti-biofilm activity of KpJH46Φ2, minocycline and the combination thereof was evaluated against a preformed biofilm of the patient's isolate and determined by safranin staining. RESULTS: Phage therapy resulted in resolution of local symptoms and signs of infection and recovery of function. The patient did not experience treatment-related adverse effects and remained asymptomatic 34 weeks after completing treatment while still receiving minocycline. A trend in biofilm biomass reduction was noted 22 hours after exposure to KpJH46Φ2 (P = .063). The addition of phage was associated with a satisfactory outcome in this case of intractable biofilm-associated prosthetic knee infection. Pending further studies to assess its efficacy and safety, phage therapy holds promise for treatment of device-associated infections.

Combining bacteriophages with cefiderocol and meropenem/vaborbactam to treat a pan-drug resistant Achromobacter species infection in a pediatric cystic fibrosis patient.

Cystic fibrosis is associated with significant morbidity and early mortality due to recurrent acute and chronic lung infections. The chronic use of multiple antibiotics without pathogen eradication increases the possibility of extensive drug resistance or even pan-drug resistance (PDR). It is imperative that new or alternative treatment options be explored. We present a clinical case of a 10-year-old female cystic fibrosis patient, infected with a PDR Achromobacter spp. She was treated with cefiderocol, meropenem/vaborbactam, and bacteriophage therapy (Ax2CJ45ϕ2) during two separate admissions in an attempt to clear her infection and restore baseline pulmonary function. The Centers for Disease Control and Prevention confirmed antibiotic susceptibilities, which showed resistance to both cefiderocol and meropenem/vaborbactam. However, after using all three agents concomitantly during the second treatment course, our patient's pulmonary function improved dramatically, and the Achromobacter spp. could not be isolated from sputum samples obtained 8 and 16 weeks after completion of therapy. Overall, the treatment regimen consisting of cefiderocol, meropenem/vaborbactam, and bacteriophage was safe and well-tolerated in our patient.

Salvage Bacteriophage Therapy for a Chronic MRSA Prosthetic Joint Infection.

This is a case of a 72 year old male with a chronic methicillin-resistant Staphylococcus aureus prosthetic joint infection. After the third intravenous dose of bacteriophage therapy, an unusual, reversible transaminitis prompted stoppage of bacteriophage therapy. Nevertheless, treatment was successful and the patient's severe chronic infection was eradicated.

Phage-Mediated Molecular Detection (PMMD): A Novel Rapid Method for Phage-Specific Bacterial Detection.

Bacterial infections pose a challenge to human health and burden the health care system, especially with the spread of antibiotic-resistant populations. To provide effective treatment and improved prognosis, effective diagnostic methods are of great importance. Here we present phage-mediated molecular detection (PMMD) as a novel molecular method for the detection and assessment of bacterial antibiotic resistance. This technique consists of a brief incubation, of approximately ten minutes, of the biological sample with a natural bacteriophage (phage) targeting the bacteria of interest. This is followed by total RNA extraction and RT-PCR. We applied this approach to Staphylococcus aureus (SA), a major causative agent of human bacterial infections. PMMD demonstrated a high sensitivity, rapid implementation, and specificity dependent on the phage host range. Moreover, due to the dependence of the signal on the physiological state of the bacteria, PMMD can discriminate methicillin-sensitive from methicillin-resistant SA (MSSA vs. MRSA). Finally, we extended this method to the detection and antibiotic sensitivity determination of other bacteria by proving PMMD efficacy for Bacillusanthracis.

Cardioversion in recent onset atrial fibrillation. / Cardioversión en la fibrilación auricular de reciente comienzo.

OBJECTIVES: To analyze heart rate control in hospital emergency departments and outcomes in patients with recent onset atrial fibrillation (AF) so that targets for improvement can be identified. MATERIAL AND METHODS: Multicenter, prospective observational cross-sectional study in a representative sample of 124 hospitals of the Spanish health services, based on records in the HERMES-AF database (Hospital Emergency Department Management Strategies for AF) for May 23 to June 5, 2011. Patients with symptomatic AF within 48 hours of onset were enrolled when the decision was made to attempt restoration of sinus rhythm. RESULTS: We included 337 patients. Chemical cardioversion was used in 311 (92.3%) and electrical cardioversion in 52 (15%), after drugs had failed in half the cases. Sinus rhythm was restored in 278 patients (82.5%), and symptoms resolved in 94%. Adverse effects were recorded in 0.9% but none were serious. Amiodarone was independently associated with a lower rate of restored sinus rhythm (odds ratio [OR], 0.442; 95% CI, 0.238-0.823; P=.01) than electrical cardioversion (OR, 4.0; 95% CI, 1.2-13.3; P=.024). The use of class Ic antiarrhythmic agents was associated with a higher percentage of discharges in less than 6 hours (OR, 2.6; 95% CI, 1.6-4.3; P< .001), and amiodarone was associated with hospital stays longer than 24 hours (OR, 2.7; 95% CI, 1.5-4.8; P< .003). CONCLUSION: Emergency department restoration of sinus rhythm in patients with AF is safe, effective, and associated with clinical benefits. Quality of care could be improved by replacing the use of amiodarone with faster and more effective treatments such as electrical cardioversion or the use of class Ic agents.

OBJETIVO: Este estudio analiza el control del ritmo en los servicios de urgencias (SUH) y sus resultados en pacientes con fibrilación auricular (FA) de reciente comienzo, para identificar áreas de mejora en el manejo. METODO: Estudio multicéntrico, observacional, prospectivo y transversal desarrollado en 124 SUH representativos del sistema sanitario español basado en el registro HERMES-AF (estrategias de manejo en el servicio de urgencias hospitalario de la FA) del 23 de mayo al 5 de junio de 2011. Se incluyeron pacientes con FA sintomática con menos de 48 h de evolución en los cuales se tomó la decisión de restaurar el ritmo sinusal. RESULTADOS: Se incluyeron 337 pacientes, se optó por cardioversión farmacológica en 311 pacientes (92,3%), y por cardioversión eléctrica en 52 (15%), la mitad de los casos tras fracaso de los fármacos. Se obtuvo ritmo sinusal (RS) en 278 pacientes (82,5%) y el alivio de los síntomas en 297 (94%), con una tasa de efectos adversos del 0,9%, ninguno grave. Amiodarona se asoció de manera independiente a una menor tasa de RS al alta (OR = 0,442; IC 95% 0,238-0,823; p = 0,01), al contrario que la cardioversión eléctrica (OR = 4,0; IC 95% 1,2-13,3; p = 0,024). Los fármacos I-C se asociaron con una mayor proporción de altas en < 6 h (OR 2,6; IC 95% 1,6-4,3; p < 0,001) y amiodarona con más estancias prolongadas de > 24 h (OR 2,7, IC 95% 1,5-4,8; p < 0,003). CONCLUSIONES: En los SUH, la restauración del RS en la FA de reciente comienzo es segura, efectiva y asocia beneficios clínicos para los pacientes. Reemplazar amiodarona por técnicas más efectivas y rápidas como la cardioversión eléctrica o los fármacos I-C es un área de mejora de la calidad asistencial.

Successful Treatment of Antibiotic-resistant, Poly-microbial Bone Infection With Bacteriophages and Antibiotics Combination.

A patient with a trauma-related left tibial infection associated with extensively drug-resistant Acinetobacter baumannii and multidrug-resistant Klebsiella pneumoniae was treated with bacteriophages and antibiotics. There was rapid tissue healing and positive culture eradication. As a result, the patient's leg did not have to be amputated and he is undergoing rehabilitation.

Benefits of Rhythm Control and Rate Control in Recent-onset Atrial Fibrillation: The HERMES-AF Study.

BACKGROUND: Although rhythm control has failed to demonstrate long-term benefits over rate control in longstanding episodes of atrial fibrillation (AF), there is little evidence concerning recent-onset ones. We analyzed the benefits of rhythm and rate control in terms of symptoms alleviation and need for hospital admission in patients with recent-onset AF. METHODS: This was a multicenter, observational, cross-sectional study with prospective standardized data collection carried out in 124 emergency departments (EDs). Clinical variables, treatment effectiveness, and outcomes (control of symptoms, final disposition) were analyzed in stable patients with recent-onset AF consulting for AF-related symptoms. RESULTS: Of 421 patients included, rhythm control was chosen in 352 patients (83.6%), a global effectiveness of 84%. Rate control was performed in 69 patients (16.4%) and was achieved in 67 (97%) of them. Control of symptoms was achieved in 396 (94.1%) patients and was associated with a heart rate after treatment ≤ 110 beats/min (odds ratio [OR] = 14.346, 95% confidence interval [CI] = 3.90 to 52.70, p < 0.001) and a rhythm control strategy (OR = 2.78, 95% CI = 1.02 to 7.61, p = 0.046). Sixty patients (14.2%) were admitted: discharge was associated with a rhythm control strategy (OR = 2.22, 95% CI = 1.20-4.60, p = 0.031) and admission was associated with a heart rate > 110 beats/min after treatment (OR = 29.71, 95% CI = 7.19 to 123.07, p < 0.001) and acute heart failure (OR = 9.45, 95% CI = 2.91 to 30.65, p < 0.001). CONCLUSION: In our study, recent-onset AF patients in whom rhythm control was attempted in the ED had a high rate of symptoms' alleviation and a reduced rate of hospital admissions.