Low-volume enrichment method supports high throughput bacteriophage screening and isolation from wastewater.

Bacteriophage therapy is a rapidly growing field of study. Narrow host ranges, bacterial resistance, and limited antibiotic availability make lytic phages a feasible therapeutic potential. Phage discovery, a critical step in developing phage therapy, is a pathway to accessible treatment. This has always been a laborious, time-consuming and resource-intensive process. In this paper, we describe a 96-well plate low-volume bacteriophage enrichment method with concentrated environmental sources to rapidly discover and isolate phages targeting multiple organisms simultaneously. Samples from natural water sources, wastewater influent, and activated sludge were tested in large volume enrichment cultures and low-volume 96-well plate format. Each plate has the capacity to run as many as 48 different combinations with multiple bacterial hosts. The time to identify the presence of phage in a sample was 5 to 10 hours in the low-volume format versus a minimum of 2 days in the traditional enrichment method. The labor and expense involved also favor the 96-well plate format. There was some loss of discovered phages using this technique, primarily targeting bacterial species less prevalent in the environment. This is an easily modifiable method that is amenable to automation and a variety of potential phage sources.

Decreased Clinical Severity of Pediatric Acute COVID-19 and MIS-C and Increase of Incidental Cases during the Omicron Wave in Comparison to the Delta Wave.

This study describes differences in clinical presentation in hospitalized children with acute COVID-19 and MIS-C between the Delta and Omicron (BA.1.1) waves in a tertiary children's hospital. This retrospective cohort study with case adjudication of hospitalized children with SARS-CoV-2-positive testing or MIS-C diagnosis occurred during the Delta and Omicron waves, from August 2021 until February 2022. There were no differences noted by race, but both waves disproportionally affected black children (24% and 25%). Assigned by a three-person expert panel, incidental diagnoses were higher in the Omicron wave (34% versus 19%). Hospitalization rates of non-incidental cases were higher during Omicron (3.8 versus 5.9 per 1000 PCR-positive community cases). Respiratory-related admissions were prominent during Delta, while Omicron clinical presentations varied, including a high number of cases of croup and seizures. Length of stay and ICU use during Omicron was significantly less than Delta for MIS-C and acute cases. Estimation of vaccination efficacy for preventing hospital admissions was 85.1-91.7% in the early Omicron period. Our estimates suggest that a protective role for vaccination continues into the Omicron wave. The high rate of incidental cases during the Omicron wave should be considered when reviewing more cursory summative data sets. This study emphasizes the need for continued clinical suspicion of COVID-19 even when lower respiratory symptoms are not dominant.

Respiratory Failure in an Extremely Premature Neonate with COVID-19.

Coronavirus disease 2019 (COVID-19), a condition associated with SARS-CoV-2, typically results in mild infection in infants and children. However, children with risk factors such as chronic lung disease and immunosuppression have higher risk of severe illness from COVID-19. We report a case of a 27-week-gestation extremely premature infant born to a mother with COVID-19 infection. The infant, initially treated for surfactant deficiency, developed worsening hypoxic respiratory failure on the fifth day of life requiring escalating ventilatory support, an elevated level of C-reactive protein, thrombocytopenia, and an elevated level of d-dimer. The infant was positive for SARS-CoV-2 by RT-PCR from Day 1 to Day 42 of his life. The infant responded to a seven-day course of dexamethasone with a gradually decreasing oxygen requirement and could be extubated to non-invasive ventilation by the end of the fifth week after birth. The infant is currently on home oxygen by nasal cannula. Prolonged shedding of the virus may be a unique feature of the disease in premature infants. Extreme prematurity, immature lungs, and an immunocompromised status may predispose these infants to severe respiratory failure and a prolonged clinical course. Instituting appropriate COVID-19 protocols to prevent the spread of the disease in the neonatal intensive care unit (NICU) is of utmost importance. Infection with SARS-CoV-2 may have implications in the management of extremely premature infants in the NICU.