A Retrospective Database Analysis of Before and After Social Distancing in Relation to Pediatric Infection Rate and Healthcare Services Usage During the Coronavirus Disease 2019 Pandemic.

BACKGROUND: Social distancing policy was introduced in Israel in 2020 to reduce the spread of coronavirus disease 2019 (COVID-19). The aim of this study was to analyze the effect of social distancing on other infections in children, by comparing disease rate and healthcare utilization before and after social distancing. METHODS: This was a before-and-after study. Within this retrospective database analysis of parallel periods in 2019 (periods 1 and 2) and 2020 (periods 3 [prelockdown period] and 4 [lockdown period]) we included all pediatric population registered in the electronic medical records of the Maccabi Healthcare Services, Israel, looking at the occurrence of non-COVID-19 infections, antibiotic purchasing, physician visits, ambulatory emergency care center visits, emergency department visits, and hospitalizations. RESULTS: A total of 776 828 children were included from 2019, and 777 729 from 2020. We found a lower infection rate in 2020 versus 2019. We did not find a difference in infection rate between periods 1 and 2, while there was a significant difference between periods 3 and 4. We found a significant difference between periods 2 and 4, with a higher RR than for the comparison between periods 1 and 3. There was a modest decrease in ambulatory emergency care center visits in 2020, and lower increases in emergency department visits and hospital admissions. We found decreases in antibiotic purchasing between periods 1 and 3 and between periods 2 and 4, more pronounced in 2020 than in 2019. CONCLUSIONS: Analysis of findings before and after social distancing and masking showed reduced prevalence of non-COVID-19 pediatric infections and reduced consumption of healthcare services and antibiotics related with the lockdown period.

Nationwide Outbreak of Candida auris Infections Driven by COVID-19 Hospitalizations, Israel, 2021-2022

We report an outbreak of Candida auris across multiple healthcare facilities in Israel. For the period of May 2014-May 2022, a total of 209 patients with C. auris infection or colonization were identified. The C. auris incidence rate increased 30-fold in 2021 (p = 0.00015), corresponding in time with surges of COVID-19-related hospitalization. Multilocus sequence typing revealed hospital-level outbreaks with distinct clones. A clade III clone, imported into Israel in 2016, accounted for 48.8% of typed isolates after January 2021 and was more frequently resistant to fluconazole (100% vs. 63%; p = 0.00017) and voriconazole (74% vs. 5.2%; p<0.0001) than were non-clade III isolates. A total of 23% of patients had COVID-19, and 78% received mechanical ventilation. At the hospital level, outbreaks initially involved mechanically ventilated patients in specialized COVID-19 units and then spread sequentially to ventilated non-COVID-19 patients and nonventilated patients.

Hospitalised patients with breakthrough COVID-19 following vaccination during two distinct waves in Israel, January to August 2021: a multicentre comparative cohort study.

BackgroundChanging patterns of vaccine breakthrough can clarify vaccine effectiveness.AimTo compare breakthrough infections during a SARS-CoV-2 Delta wave vs unvaccinated inpatients, and an earlier Alpha wave.MethodsIn an observational multicentre cohort study in Israel, hospitalised COVID-19 patients were divided into three cohorts: breakthrough infections in Comirnaty-vaccinated patients (VD; Jun-Aug 2021) and unvaccinated cases during the Delta wave (ND) and breakthrough infections during an earlier Alpha wave (VA; Jan-Apr 2021). Primary outcome was death or ventilation.ResultsWe included 343 VD, 162 ND and 172 VA patients. VD were more likely older (OR: 1.06; 95% CI: 1.05-1.08), men (OR: 1.6; 95% CI: 1.0-2.5) and immunosuppressed (OR: 2.5; 95% CI: 1.1-5.5) vs ND. Median time between second vaccine dose and admission was 179 days (IQR: 166-187) in VD vs 41 days (IQR: 28-57.5) in VA. VD patients were less likely to be men (OR: 0.6; 95% CI: 0.4-0.9), immunosuppressed (OR: 0.3; 95% CI: 0.2-0.5) or have congestive heart failure (OR: 0.6; 95% CI: 0.3-0.9) vs VA. The outcome was similar between all cohorts and affected by age and immunosuppression and not by vaccination, variant or time from vaccination.ConclusionsVaccination was protective during the Delta variant wave, as suggested by older age and greater immunosuppression in vaccinated breakthrough vs unvaccinated inpatients. Nevertheless, compared with an earlier post-vaccination period, breakthrough infections 6 months post-vaccination occurred in healthier patients. Thus, waning immunity increased vulnerability during the Delta wave, which suggests boosters as a countermeasure.

Spotted Fever Group Rickettsioses in Israel, 2010-2019.

In a multicenter, nationwide, retrospective study of patients hospitalized with spotted fever group rickettsiosis in Israel during 2010-2019, we identified 42 cases, of which 36 were autochthonous. The most prevalent species was the Rickettsia conorii Israeli tick typhus strain (n = 33, 79%); infection with this species necessitated intensive care for 52% of patients and was associated with a 30% fatality rate. A history of tick bite was rare, found for only 5% of patients; eschar was found in 12%; and leukocytosis was more common than leukopenia. Most (72%) patients resided along the Mediterranean shoreline. For 3 patients, a new Rickettsia variant was identified and had been acquired in eastern, mountainous parts of Israel. One patient had prolonged fever before admission and clinical signs resembling tickborne lymphadenopathy. Our findings suggest that a broad range of Rickettsia species cause spotted fever group rickettsiosis in Israel.

Cat Scratch Disease Presenting as Fever of Unknown Origin Is a Unique Clinical Syndrome.

BACKGROUND: Fever of unknown origin (FUO) is a rare manifestation of cat scratch disease (CSD). Data regarding CSD-associated FUO (CSD-FUO), particularly in adults, are limited. We aimed to study disease manifestations and long-term clinical outcome. METHODS: A national CSD surveillance study has been conducted in Israel since 1991. Data are obtained using questionnaires, review of medical records, and telephone interviews. FUO was defined as fever of ≥14 days without an identifiable cause. CSD-FUO patients were identified in the 2004-2017 CSD national registry. Follow-up included outpatient clinic visits and telephone/e-mail surveys. RESULTS: The study included 66 CSD-FUO patients. Median age was 35.5 years (range, 3-88). Median fever duration was 4 weeks (range, 2-9). Relapsing fever pattern was reported in 52% of patients, weight loss in 57%, and night sweats in 48%. Involvement of ≥1 organs occurred in 59% of patients; hepatosplenic space-occupying lesions (35%), abdominal/mediastinal lymphadenopathy (20%), ocular disease (18%), and multifocal osteomyelitis (6%) were the most common. Malignancy, particularly lymphoma, was the initial radiological interpretation in 21% of patients; 32% underwent invasive diagnostic procedures. Of the 59 patients available for follow-up (median duration, 31 weeks; range, 4-445), 95% had complete recovery; 3 patients remained with ocular sequelae. CONCLUSION: This is the first attempt to characterize CSD-FUO as a unique syndrome that may be severe and debilitating and often mimics malignancy. Relapsing fever is a common clinical phenotype. Multiorgan involvement is common. Recovery was complete in all patients except in those with ocular disease.

Fourier Transform Infrared Spectroscopy Is a New Option for Outbreak Investigation: a Retrospective Analysis of an Extended-Spectrum-Beta-Lactamase-Producing Klebsiella pneumoniae Outbreak in a Neonatal Intensive Care Unit.

The IR Biotyper is a new automated typing system based on Fourier-transform infrared (FT-IR) spectroscopy that gives results within 4 h. We aimed (i) to use the IR Biotyper to retrospectively analyze an outbreak of extended-spectrum beta-lactamase-producing Klebsiella pneumoniae (ESBL-KP) in a neonatal intensive care unit and to compare results to BOX-PCR and whole-genome sequencing (WGS) results as the gold standard and (ii) to assess how the cutoff values used to define clusters affect the discriminatory power of the IR Biotyper. The sample consisted of 18 isolates from 14 patients. Specimens were analyzed in the IR Biotyper using the default analysis settings, and spectra were analyzed using OPUS 7.5 software. The software contains a feature that automatically proposes a cutoff value to define clusters; the cutoff value defines up to which distance the spectra are considered to be in the same cluster. Based on FT-IR, the outbreak represented 1 dominant clone, 1 secondary clone, and several unrelated clones. FT-IR results, using the cutoff value generated by the accompanying software after 4 replicates, were concordant with WGS for all but 1 isolate. BOX-PCR was underdiscriminatory compared to the other two methods. Using the cutoff value generated after 12 replicates, the results of FT-IR and WGS were completely concordant. The IR Biotyper can achieve the same typeability and discriminatory power as genome-based methods. However, to attain this high performance requires either previous, strain-dependent knowledge about the optimal technical parameters to be used or validation by a second method.

Antibiotic treatment for invasive nonpregnancy-associated listeriosis and mortality: a retrospective cohort study.

Little evidence exists addressing the clinical value of adding gentamicin to ampicillin for invasive listeriosis. A multicenter retrospective observational study of nonpregnant adult patients with invasive listeriosis (primary bacteremia, central nervous system (CNS) disease, and others) in 11 hospitals in Israel between the years 2008 and 2014 was conducted. We evaluated the effect of penicillin-based monotherapy compared with early combination therapy with gentamicin, defined as treatment started within 48 h of culture results and continued for a minimum of 7 days. Patients who died within 48 h of the index culture were excluded. The primary outcome was 30-day all-cause mortality. A total of 190 patients with invasive listeriosis were included. Fifty-nine (30.6%) patients were treated with early combination therapy, 90 (46.6%) received monotherapy, and 44 (22.8%) received other treatments. Overall 30-day mortality was 20.5% (39/190). Factors associated with mortality included lower baseline functional status, congestive heart failure, and higher sequential organ failure assessment score. Source of infection, treatment type, and time from culture taken date to initiation of effective therapy were not associated with mortality. In multivariable analysis, monotherapy was not significantly associated with increased 30-day mortality compared with early combination therapy (OR 1.947, 95% CI 0.691-5.487). Results were similar in patients with CNS disease (OR 3.037, 95% CI 0.574-16.057) and primary bacteremia (OR 2.983, 95% CI 0.575-15.492). In our retrospective cohort, there was no statistically significant association between early combination therapy and 30-day mortality. A randomized controlled trial may be necessary to assess optimal treatment.

Ibrutinib-associated invasive fungal diseases in patients with chronic lymphocytic leukaemia and non-Hodgkin lymphoma: An observational study.

BACKGROUND: Invasive fungal diseases (IFD) are life-threatening infections most commonly diagnosed in acute leukaemia patients with prolonged neutropenia and are uncommonly diagnosed in patients with lymphoproliferative diseases. OBJECTIVES: Following the initial report of aspergillosis diagnosed shortly after beginning ibrutinib for chronic lymphocytic leukaemia, a survey was developed to seek additional cases of IFD during ibrutinib treatment. METHODS: Local and international physicians and groups were approached for relevant cases. Patients were included if they met the following criteria: diagnosis of chronic lymphocytic leukaemia/non-Hodgkin lymphoma; proven or probable IFD; and ibrutinib treatment on the date IFD were diagnosed. Clinical and laboratory data were captured using REDCap software. RESULT: Thirty-five patients with IFD were reported from 22 centres in eight countries: 26 (74%) had chronic lymphocytic leukaemia. The median duration of ibrutinib treatment before the onset of IFD was 45 days (range 1-540). Aspergillus species were identified in 22 (63%) of the patients and Cryptococcus species in 9 (26%). Pulmonary involvement occurred in 69% of patients, cranial in 60% and disseminated disease in 60%. A definite diagnosis was made in 21 patients (69%), and the mortality rate was 69%. Data from Israel regarding ibrutinib treated patients were used to evaluate a prevalence of 2.4% IFD. CONCLUSIONS: The prevalence of IFD among chronic lymphocytic leukaemia/non-Hodgkin lymphoma patients treated with ibrutinib appears to be higher than expected. These patients often present with unusual clinical features. Mortality from IFD in this study was high, indicating that additional studies are urgently needed to identify patients at risk for ibrutinib-associated IFD.

Two Cases of Israeli Spotted Fever with Purpura Fulminans, Sharon District, Israel.

We report a series of 5 case-patients who had Israeli spotted fever, of whom 2 had purpura fulminans and died. Four case-patients were given a diagnosis on the basis of PCR of skin biopsy specimens 3-4 days after treatment with doxycycline; 1 case-patient was given a diagnosis on the basis of seroconversion. Rickettsia spp. from the 2 case-patients who died were sequenced and identified as Rickettsia conorii subsp. israelensis. Purpura fulminans has been described in association with R. rickettsii and R. indica, but rarely with R. conorii subsp. israelensis.

Diagnostic and therapeutic yield of imaging studies in Polymicrobial and Monomicrobial Gram-negative bloodstream infections - a retrospective cohort study.

PURPOSE: Appropriate antimicrobial therapy and surgical drainage, improve survival in patients with Gram negative bloodstream infections (BSI). Data about the yield of imaging studies in polymicrobial BSI is sparse. The aim of the study was to assess the need for imaging studies and surgical drainage among patients with polymicrobial compared to monomicrobial BSI. RESULTS: In a retrospective cohort study of adult patients with Gram negative BSI, 135 patients with monomicrobial BSI were compared to 82 with polymicrobial BSI. Imaging studies were performed in 56.3 % of patients with monomicrobial BSI and in 50 % of polymicrobial BSI (p=0.4), surgical drainage was performed in 20.1 % of patients with monomicrobial BSI and 27.2 % of polymicrobial BSI (p=0.25). Surgical drainage was performed in 26.2 % of patients who survived vs. 11.8 % of patients who died (p=0.035). CONCLUSIONS: There is no difference in the diagnostic approach to monomicrobial and polymicrobial Gram-negative BSI. Surgical drainage is associated with decreased mortality.

The Prognostic Value of Serology in Persistent Q Fever Infection.

Background: Q fever has significant consequences for patients with persistent localized infection. A combination of doxycycline with hydroxychloroquine, for at least 18-24 months, is the first-line therapy. The use of serology as a prognostic marker during therapy is controversial. Methods: A retrospective, observational cohort study in two outpatient clinics in northern Israel. All adults with persistent Q fever (2015-2021) were included in the study. Clinical failure was defined as relapse or death related to Q fever after end of treatment (EOT). Serological cure was defined as phase 1 IgG ≤800 or a four-fold decrease at EOT. Results: Twenty-two patients were included in the study, with a median follow up of 40 months (IQR = 28.5-63.5), and median treatment duration of 28.5 months (IQR = 21.8-50.5). Clinical cure occurred in 18 patients (82%), serological cure in 10 (45%). Phase 1 IgG at presentation was significantly higher in the clinical failure group (median 9600 vs. 3200 in the clinical cure group, p = 0.019), and at 6-12 months after EOT (median 6400 vs. 800 respectively, p = 0.03). Phase 1 IgG levels at 1 year and EOT were similar in both groups. Positive phase 2 IgM after one year of therapy correlated with clinical failure (p = 0.038), but not at EOT or after EOT. Conclusion: Phase 1 IgG levels at presentation, phase 2 IgM at 1 year, and Phase 1 IgG 6-12 months after EOT were associated with clinical failure in patients with persistent Q fever.

An emergency department intervention to improve earlier detection of community-onset bloodstream infection among hospitalized patients.

BACKGROUND: Blood cultures (BCs) are essential microbiologic tests, but blood culturing diagnostic stewardship is frequently poor. We aimed to study the process-related failures and to evaluate the effect of an emergency department (ED) intervention on BCs collection practices and yield. METHODS: We implemented an ED-quality improvement intervention including educational sessions, phlebotomists addition, promoting single-site strategy for BC-collection and preanalytical data feedback. BC-bottles collected, positive BCs, blood volumes and documentation of collection times were measured, before (December 2021-August 2022) and after (September 2022-July 2023) intervention. Results were corrected to hospitalizations admissions or days. We used interrupted-time series analyses for comparisons. RESULTS: A total of 64,295 BC bottles were evaluated, 26,261 before and 38,034 postintervention. The median ED-BCs collected per week increased from 88 to 105 BCs (P < .0001), resulting from increased early sampling (P = .0001). Solitary BCs decreased (95%-28%), documented times increased (2.8%-25%), and average blood volume increased (3 mL to 4.5 mL) postintervention. Community-onset Bloodstream infections (BSIs) increased (39.6-52 bottles/1,000 admissions, P = .0001), while Health care-associated BSIs decreased (39-27 bottles/10,000 days, P = .0042). Contamination rates did not change. CONCLUSIONS: An ED-focused intervention based on the education sessions and single-site strategy improved culturing stewardship and facilitated the early identification of BSI without an increase in contamination.

An international multicenter study comparing COVID-19 omicron outcomes in patients with hematological malignancies treated with obinutuzumab versus rituximab.

OBJECTIVES: Hematological malignancy (HM) patients treated with anti-CD20 monoclonal antibodies are at higher risk for severe COVID-19. A previous single-center study showed worse outcomes in patients treated with obinutuzumab compared to rituximab. We examined this hypothesis in a large international multicenter cohort. METHODS: We included HM patients from 15 centers, from five countries treated with anti-CD20, comparing those treated with obinutuzumab (O-G) to rituximab (R-G) between December 2021 and June 2022, when Omicron lineage was dominant. RESULTS: We collected data on 1048 patients. Within the R-G (n = 762, 73%), 191 (25%) contracted COVID-19 compared to 103 (36%) in the O-G. COVID-19 patients in the O-G were younger (61 ± 11.7 vs. 64 ± 14.5, p = 0.039), had more indolent HM diagnosis (aggressive lymphoma: 3.9% vs. 67.0%, p < 0.001), and most were on maintenance therapy at COVID-19 diagnosis (63.0% vs. 16.8%, p < 0.001). Severe-critical COVID-19 occurred in 31.1% of patients in the O-G and 22.5% in the R-G. In multivariable analysis, O-G had a 2.08-fold increased risk for severe-critical COVID-19 compared to R-G (95% CI 1.13-3.84), adjusted for Charlson comorbidity index, sex, and tixagevimab/cilgavimab (T-C) prophylaxis. Further analysis comparing O-G to R-G demonstrated increased hospitalizations (51.5% vs. 35.6% p = 0.008), ICU admissions (12.6% vs. 5.8%, p = 0.042), but the nonsignificant difference in COVID-19-related mortality (n = 10, 9.7% vs. n = 12, 6.3%, p = 0.293). CONCLUSIONS: Despite younger age and a more indolent HM diagnosis, patients receiving obinutuzumab had more severe COVID-19 outcomes than those receiving rituximab. Our findings underscore the need to evaluate the risk-benefit balance when considering obinutuzumab therapy for HM patients during respiratory viral outbreaks.

Anthropogenic and natural disturbances along a river and its estuary alter the diversity of pathogens and antibiotic resistance mechanisms.

Antibiotic resistance (AMR) in pathogens threatens human health worldwide, and antibiotic-resistant bacteria (ARB) are widespread in the environment. In particular, anthropogenically-disturbed rivers became reservoirs of ARBs and hotspots of antibiotic resistance gene (ARG) transmission. However, the diversity and sources of ARB, and the mechanisms of ARG transmission are not fully known. Here, we used deep metagenomic sequencing to study the dynamics of pathogens and their antibiotic resistance mechanisms along the Alexander River (Israel), affected by sewage and animal farm runoffs. Putative pathogens such as Aeromicrobium marinum and Mycobacterium massilipolynesiensis were enriched in western stations, following the inputs of polluted Nablus River. Aeromonas veronii was dominant in eastern stations in Spring. Several AMR mechanisms showed distinct patterns in Summer-Spring (dry season) and Winter (rainy season). We found low abundance beta-lactamases conferring carbapenem resistance: e.g., OXA-912 was linked to A. veronii in Spring; OXA-119 and OXA-205 to Xanthomonadaceae in Winter. We classified 33 % of ARG-containing contigs as putative plasmid sequences, indicating the high potential for resistome transmission. A limited number of ARGs were linked to putative phages. Our results suggest that this model river is a hotspot for AMR activity and transmission, and highlight the merit of deep sequencing for AMR discovery.

Exposure to Non-Antimicrobial Drugs and Risk of Infection with Antibiotic-Resistant Enterobacteriaceae.

Antimicrobial resistance (AMR) has consistently been linked to antibiotic use. However, the roles of commonly prescribed non-antimicrobial drugs as drivers of AMR may be under-appreciated. Here, we studied a cohort of patients with community-acquired pyelonephritis and assessed the association of exposure to non-antimicrobial drugs at the time of hospital admission with infection with drug-resistant organisms (DRO). Associations identified on bivariate analyses were tested using a treatment effects estimator that models both outcome and treatment probability. Exposure to proton-pump inhibitors, beta-blockers, and antimetabolites was significantly associated with multiple resistance phenotypes. Clopidogrel, selective serotonin reuptake inhibitors, and anti-Xa agents were associated with single-drug resistance phenotypes. Antibiotic exposure and indwelling urinary catheters were covariates associated with AMR. Exposure to non-antimicrobial drugs significantly increased the probability of AMR in patients with no other risk factors for resistance. Non-antimicrobial drugs may affect the risk of infection with DRO through multiple mechanisms. If corroborated using additional datasets, these findings offer novel directions for predicting and mitigating AMR.

High rate of bacterial respiratory tract co-infections upon admission amongst moderate to severe COVID-19 patients.

BACKGROUND: The role of bacterial and viral co-infection in the current COVID-19 pandemic remains elusive. The aim of this study was to describe the rates and features of co-infection on admission of COVID-19 patients, based on molecular and routine laboratory methods. METHODS: A retrospective study of COVID-19 and non-COVID-19 patients undergoing Biofire®, FilmArray® Pneumonia Panel, bioMérieux, and routine cultures during the first 3 days from admission, between June 2019 and March 2021. RESULTS: FilmArray tests were performed in 115 COVID-19 and in 61 non-COVID-19 patients. Most (>99%) COVID-19 patients had moderate-critical illness, 37% required mechanical ventilation. Sputa and endotracheal aspirates were the main samples analyzed. Positive FilmArray tests were found in 60% (70/116) of the tests amongst COVID-19 patients and 62.5% (40/64) amongst non-COVID-19 patients. All 70 cases were positive for bacterial targets, while one concomitant virus (Rhinovirus/Enterovirus) and one Legionella spp. were detected. The most common bacterial targets were Haemophilus influenzae (36%), Staphylococcus aureus (23%), Streptococcus pneumoniae (10%) and Enterobacter cloacae (10%). Correlation between FilmArray and cultures was found in 81% and 44% of negative and positive FA tests, respectively. Positive FilmArray results typically (81%) triggered the administration of antibiotic therapy and negative results resulted in antimicrobials to be withheld in 56% of cases and stopped in 8%. Bacterial cultures of COVID-19 patients were positive in 30/88 (34%) of cases. CONCLUSIONS: Bacterial co-infection is common amongst moderate-critical COVID-19 patients on admission while viral and atypical bacteria were exceedingly rare. Positive FilmArray results could trigger potentially unnecessary antibiotic treatment.KEY POINTWe found high rates of on-admission bacterial co-infection amongst hospitalized moderate to severe COVID-19 patients. Molecular tests (Biofire, FilmArray) and routine microbiological tests revealed 60% and 34% bacterial co-infection, respectively, while viral and fungal co-infections were rare.

Invasive Fungal Diseases in Hospitalized Patients with COVID-19 in Israel: A Multicenter Cohort Study.

Highly variable estimates of COVID-19-associated fungal diseases (IFDs) have been reported. We aimed to determine the incidence of clinically important fungal diseases in hospitalized COVID-19 patients during the first year of the pandemic. We performed a multicenter survey of IFDs among patients hospitalized with COVID-19 in 13 hospitals in Israel between February 2020 and May 2021. COVID-19-associated pulmonary mold disease (PMD) and invasive candidiasis (IC) were defined using ECMM/ISHAM and EORTC/MSG criteria, respectively. Overall rates of IC and PMD among patients with critical COVID-19 were 10.86 and 10.20 per 1000 admissions, respectively, with significant variability among medical centers. PMD rates were significantly lower in centers where galactomannan was a send-out test versus centers with on-site testing (p = 0.035). The 30-day mortality rate was 67.5% for IC and 57.5% for PMD. Treatment with an echinocandin for IC or an extended-spectrum azole for PMD was associated with significantly lower mortality rates (adjusted hazard ratio [95% confidence interval], 0.26 [0.07-0.91] and 0.23 [0.093-0.57], respectively). In this multicenter national survey, variable rates of PMD were associated with on-site galactomannan testing, suggesting under-detection in sites lacking this capacity. COVID-19-related IFDs were associated with high mortality rates, which were reduced with appropriate antifungal therapy.

Sparse Convolutional Beamforming for 3-D Ultrafast Ultrasound Imaging.

Real-time 3-D ultrasound (US) provides a complete visualization of inner body organs and blood vasculature, crucial for diagnosis and treatment of diverse diseases. However, 3-D systems require massive hardware due to the huge number of transducer elements and consequent data size. This increases cost significantly and limit both frame rate and image quality, thus preventing the 3-D US from being common practice in clinics worldwide. A recent study presented a technique called sparse convolutional beamforming algorithm (SCOBA), which obtains improved image quality while allowing notable element reduction in the context of 2-D focused imaging. In this article, we build upon previous work and introduce a nonlinear beamformer for 3-D imaging, called COBA-3D, consisting of 2-D spatial convolution of the in-phase and quadrature received signals. The proposed technique considers diverging-wave transmission and achieves improved image resolution and contrast compared with standard delay-and-sum beamforming while enabling a high frame rate. Incorporating 2-D sparse arrays into our method creates SCOBA-3D: a sparse beamformer that offers significant element reduction and, thus, allows performing 3-D imaging with the resources typically available for 2-D setups. To create 2-D thinned arrays, we present a scalable and systematic way to design 2-D fractal sparse arrays. The proposed framework paves the way for affordable ultrafast US devices that perform high-quality 3-D imaging, as demonstrated using phantom and ex-vivo data.

Molecular Epidemiology of Methicillin-Resistant Staphylococcus aureus Clinical Isolates during 7.5 Years in One Regional Hospital in Israel.

Background: The clonal repertoire of community-associated Methicillin-resistant Staphylococcus aureus (CA-MRSA) strains appear to differ between hospitals and geographic locations. We aimed to study the molecular epidemiology of MRSA infections in our regional hospital in Israel. Methods: A retrospective analysis of MRSA isolates from hospitalized patients, which underwent spa typing between 2012 and 2019. Mainly, MRSA-bloodstream isolates were typed. Isolates were grouped into healthcare-associated (HcA) or community-associated (CA). HcA were further divided into hospital-related or long-term care facility- (LTCF-) related. Several representatives underwent SCCmec typing. Results: We analyzed 166 clinical MRSA isolates: 115 (70%) bloodstream, 42 (25%) wounds/abscesses, and 9 (5%) screening isolates. 145 (87%) were HcA, and 21 (13%) were CA. Common (72%) spa types were t002, t032, t008, t001, and t065. Eighty (55%) isolates were attributed to LTCFs and 65 isolates to our hospital, both showing similar spa types distribution. The most prevalent spa type among patients with HcA infection was t002 (50 isolates, 32%), followed by t032, t065, t578, t008, and t001. Most (88/115, 77%) bloodstream infections (BSIs) were HcA, typically occurring in the same facility in which the infection was acquired. In 27 cases (23%), the BSI developed in the community setting, and in half of these cases, a previous healthcare system exposure was evident. Conclusions: The MRSA clonal population in this longitudinal study was stable and consisted mainly of molecular lineages widespread in Europe. SCCmec-IV strains play a major role in causing MRSA infections in the healthcare settings, especially in LTCFs. Community-acquired MRSA BSIs without any previous healthcare exposure are still relatively rare.