Hospitalized Patients With Severe Coronavirus Disease 2019 During the Omicron Wave in Israel: Benefits of a Fourth Vaccine Dose.

BACKGROUND: Waning immunity and an increased incidence of coronavirus disease 2019 (COVID-19) during the Omicron outbreak led the Israeli Ministry of Health to recommend a fourth vaccine dose for high-risk individuals. In this study, we assessed its effect for hospitalized patients with severe breakthrough COVID-19. METHODS: In this multicenter cohort study of hospitalized adults with severe COVID-19 in Israel, from 15 to 31 January 2022, cases were divided according to the number of vaccinations received. Poor outcome was defined as mechanical ventilation or in-hospital death and was compared between 3- and 4-dose vaccinees using logistic regression. RESULTS: Included were 1049 patients, median age 80 years. Among them, 394 were unvaccinated, 386 and 88 had received 3 or 4 doses, respectively. The 3-dose group was older, included more males, and immunosuppressed patients but with similar outcomes, 49% vs 51% compared with unvaccinated patients (P = .72). Patients who received 4 doses were similarly older and immunosuppressed but had better outcomes compared with unvaccinated patients, 34% vs 51% (P < .01). We examined independent predictors for poor outcome in patients who received either 3 or 4 doses a median of 161 days or 14 days before diagnosis, respectively. Receipt of the fourth dose was associated with protection (odds ratio, 0.51; 95% confidence interval, .3-.87), as was remdesivir. Male sex, chronic renal failure, and dementia were associated with poor outcomes. CONCLUSIONS: Among hospitalized patients with severe breakthrough COVID-19, a recent fourth dose was associated with significant protection against mechanical ventilation or death compared with 3 doses.

Genomic Epidemiology of Clinical Brucella melitensis Isolates from Southern Israel.

Brucellosis, a zoonosis mainly transmitted by consumption of unpasteurized dairy products, is endemic in Southern Israel, mainly among the Bedouin Arab population. However, the genomic epidemiology of B. melitensis in this region has not yet been elucidated. A cohort of brucellosis cases (n = 118) diagnosed between 2017-2019 was studied using whole-genome sequencing (WGS). Phylogenetic analyses utilized core genome MLST (cgMLST) for all local isolates and core genome SNPs for 347 human-associated B. melitensis genomes, including Israeli and publicly available sequences. Israeli isolates formed two main clusters, presenting a notable diversity, with no clear dominance of a specific strain. On a global scale, the Israeli genomes clustered according to their geographical location, in proximity to genomes originating from the Middle East, and formed the largest cluster in the tree, suggesting relatively high conservation. Our study unveils the genomic epidemiology of B. melitensis in Southern Israel, implicating that rather than a common source, the transmission pattern of brucellosis among Bedouin communities is complex, predominantly local, and household-based. Further, genomic surveillance of B. melitensis is expected to inform future public health and veterinary interventions and clinical care.

Secondary organizing pneumonia after recovery of mild COVID-19 infection.

A 36-year-old male with diffuse large B-cell lymphoma on maintenance rituximab therapy presented to the emergency department with high fever and fatigue. A chest X-ray showed a lobar infiltrate, 40 days before admission the patient suffered from a mild coronavirus disease 2019 (COVID-19) infection and fully recovered. PCR nasopharyngeal swab was negative for COVID-19. Comprehensive biochemical, radiological, and pathological evaluation including 18-fluorodeoxyglucose positron emission tomography with computed tomography and transbronchial lung biopsy found no pathogen or lymphoma recurrence. Treatment for pneumonia with antibiotic and antifungal agents was nonbeneficial. A diagnosis of secondary organizing pneumonia (OP) was made after pneumonia migration and a rapid response to corticosteroids. OP secondary to a viral respiratory infection has been well described. Raising awareness for post-COVID-19 OP has therapeutic and prognostic importance because those patients benefit from steroid therapy. We believe the condition described here is underdiagnosed and undertreated by doctors worldwide. Because of the ongoing global pandemic we are now encountering a new kind of patient, patients that have recovered from COVID-19. We hope that this case may contribute to gaining more knowledge about this growing patient population.

Brucellosis Outbreak Traced to Commercially Sold Camel Milk through Whole-Genome Sequencing, Israel.

Brucellosis, a neglected zoonotic disease acquired from contaminated food products, remains a public health concern worldwide. We describe an outbreak in which commercially sold camel milk containing Brucella melitensis was distributed across Israel. Whole-genome sequencing linked patients infected with B. melitensis to wholesale camel milk and unregulated livestock trade.

Genomic Characterization of Antimicrobial Resistance, Virulence, and Phylogeny of the Genus Ochrobactrum.

Ochrobactrum is a ubiquitous Gram-negative microorganism, mostly found in the environment, which can cause opportunistic infections in humans. It is almost uniformly resistant to penicillins and cephalosporins through an AmpC-like ß-lactamase enzyme class (OCH). We studied 130 assembled genomes, of which 5 were animal-derived isolates recovered in Israel, and 125 publicly available genomes. Our analysis focused on antimicrobial resistance (AMR) genes, virulence genes, and whole-genome phylogeny. We found that 76% of Ochrobactrum genomes harbored a blaOCH ß-lactamase gene variant, while 7% harbored another AmpC-like gene. No virulence genes other than lipopolysaccharide-associated genes were found. Core genome multilocus sequence typing clustered most samples to known species, but neither geographical clustering nor isolation source clustering were evident. When analyzing the distribution of different blaOCH variants as well as of the blaOCH-deficient samples, a clear phylogenomic clustering was apparent for specific species. The current analysis of the largest collection to date of Ochrobactrum genomes sheds light on the resistome, virulome, phylogeny, and species classification of this increasingly reported human pathogen. Our findings also suggest that Ochrobactrum deserves further characterization to underpin its evolution, taxonomy, and antimicrobial resistance.

Chorioamnionitis caused by Serratia marcescens in a healthy pregnant woman with preterm premature rupture of membranes: A rare case report and review of the literature.

The incidence of chorioamnionitis varies widely. The highest incidence is reported in preterm deliveries. Among preterm deliveries, chorioamnionitis usually occurs after preterm premature rupture of membranes (PPROM). To date, only five cases of chorioamnionitis due to Serratia marcescens were reported. Here we present a case of a pregnant woman with chorioamnionitis due to Serratia marcescens who delivered a premature neonate at 28 weeks and four days of gestation. We also conducted a review of the literature in order to identify and characterize the clinical presentation and outcomes of this rare infection. A 36 year old female (gravida 9, para 6) was admitted with cervical effacement of 16mm and intact membranes at gestational age of 25 weeks and five days. One week following her admission PPROM was noticed. Treatment with the standard antibiotic regimen for PPROM was initiated. Thirteen days after the diagnosis of PPROM (28 weeks and four days) she developed chills, abdominal pain, sub febrile fever, tachycardia, leukocytosis and fetal tachycardia, and a clinical diagnosis of chorioamnionitis was made. An urgent CS was performed. In the first post-operative day the patient developed surgical sight infection. Cultures obtained from the purulent discharge of the wound, as well as cultures from the placenta and uterine cavity that were obtained during surgery grew Serratia marcescens. The patient was treated with Meropenem for six days, with a good clinical response. We present a rare case of nosocomialy acquired Serratia marcescens chorioamnionitis in a patient with PPROM. This case emphasizes the need for good infection control measures. Our favorable outcome together with the scares reports in the literature, add insight into this type of rare infection.

A Burkholderia pseudomallei Infection Imported from Eritrea to Israel.

Although it has been predicted that melioidosis is probably endemic in the Horn of Africa, no confirmed cases have ever been detected in the region. We have recently isolated Burkholderia pseudomallei from an Eritrean patient in Israel. The isolate was assigned a novel multilocus sequence type (ST-1479). The observation has important epidemiological implications in an era of massive human migration.

Peripheral blood mononuclear cells of HIV-infected patients contain CD8 T cells that form conjugates with and kill HIV-infected autologous CD4 T cells.

Peripheral blood mononuclear cells (PBMC) of untreated, HIV-infected patients contain HIV-specific CD8 T cells as well as their corresponding targets, HIV-infected CD4 T cells. To determine if CD4 T-cell depletion in HIV-infected patients may result from autologous CD8-CD4 T-cell interaction, CD8 and CD4 T cells procured from PBMC of acute and chronic untreated HIV-infected patients were sorted and co-incubated. Formation of CD8-CD4 T-cell conjugates was observed by fluorescence microscopy. Apoptosis of CD4 T cells in conjugation was recorded by digitized images and was further observed and measured by FACS using Annexin staining. Perforin expression in the CD8 T cells was measured using intracellular monoclonal perforin antibody staining. HIV DNA in the conjugated CD4 T cells was detected by in situ PCR. We found that 6·1 ± 0·5% of CD4 T cells from acute HIV-infected patients and 3·0 ± 0·5% from chronic HIV-infected patients formed CD8-CD4 T-cell conjugates. Annexin binding and cell morphology typical of apoptosis were observed in the conjugated CD4 T cells. The majority of CD8 T cells that had conjugated to CD4 T cells expressed perforin. The conjugated CD4 T cells exhibited nuclear HIV DNA. CD8 T cells and HIV-infected CD4 T cells, both procured from the PBMC of untreated HIV-infected patients, form conjugates. Apoptotic lytic activity has been observed in the conjugated CD4 T cells. We propose that CD4 T-cell annihilation in HIV-infected patients results, at least in part, from the interactions of perforin-rich CD8 T cells with autologous, HIV-infected CD4 T cells.