Impact of the Sofia® Influenza A+B FIA rapid diagnostic test in a pediatric emergency department

Differential detection of H1N1 virus spiker proteins by two hexaphenylbutadiene isomers based on size-matching principle

As one of the high pathogenic influenza viruses, H1N1 virus easily induces to serious diseases, even leading to death. To date, all detection methods for H1N1 virus had shortcomings, including high equipment cost, time consumption, and etc. Therefore, a novel detection method should be established to achieve more convenient, rapid, and low-cost detection. In this work, an isomer of HPBmN-I with aggregation-induced emission characteristic was firstly synthesized on the basis of our previous reported HPBpN-I. The results showed that HPBmN-I only selectively binds to N1 in the presence of H1, while HPBpN-I can exhibit total fluorescence response to H1 and N1 in H1/N1 mixture. The limited of detection (LOD) of HPBmN-I to N1 was estimated to be 20.82 ng/mL in normal saline (NS) according to the IUPAC-based approach. The simulation calculations based on molecular docking revealed that four HPBmN-I molecules combine well with the hydrophobic cavity of N1 and achieve the fluorescence enhancement due to size matching with each other. The combination of HPBpN-I and HPBmN-I as probes was successfully used to quantitatively detect H1 and N1 in real H1N1 virus. Compared to enzyme-linked immunosorbent assay (ELISA) method, the established method not only showed the same detection accuracy but also had the advantages of real-time, ease of preparation, and low-cost, demonstrating potential market prospects.

Point-of-Care and Rapid Tests for the Etiological Diagnosis of Respiratory Tract Infections in Children: A Systematic Review and Meta-Analysis

Fever is one of the most common causes of medical evaluation of children, and early discrimination between viral and bacterial infection is essential to reduce inappropriate prescriptions. This study aims to systematically review the effects of point-of-care tests (POCTs) and rapid tests for respiratory tract infections on changing antibiotic prescription rate, length of stay, duration of therapy, and healthcare costs. Embase, MEDLINE, and Cochrane Library databases were systematically searched. All randomized control trials and non-randomized observational studies meeting inclusion criteria were evaluated using the NIH assessment tool. A meta-analysis was performed to assess the effects of rapid influenza diagnostic tests and film-array respiratory panel implementation on selected outcomes. From a total of 6440 studies, 57 were eligible for the review. The analysis was stratified by setting and POCT/rapid test type. The most frequent POCTs or rapid tests implemented were the Rapid Influenza Diagnostic Test and film-array and for those types of test a separate meta-analysis assessed a significant reduction in antibiotic prescription and an improvement in oseltamivir prescription. Implementing POCTs and rapid tests to discriminate between viral and bacterial infections for respiratory pathogens is valuable for improving appropriate antimicrobial prescriptions. However, more studies are needed to assess these findings in pediatric settings.

Rapid syndromic testing for respiratory viral infections in children attending the emergency department during COVID-19 pandemic in Lille, France, 2021-2022

OBJECTIVES

Viral respiratory infections are common in children, and usually associated with non-specific symptoms. Respiratory panel-based testing was implemented during the COVID-19 pandemic, for the rapid differentiation between SARS-CoV-2 and other viral infections, in children attending the emergency department (ED) of the teaching hospital of Lille, northern France, between February 2021 and January 2022.

METHODS

Samples were collected using nasopharyngeal swabs. Syndromic respiratory testing was performed with two rapid multiplex molecular assays: the BioFire® Respiratory Panel 2.1 - plus (RP2.1 plus) or the QIAstat-Dx Respiratory SARS-CoV-2 Panel. SARS-CoV-2 variant was screened using mutation-specific PCR-based assays and genome sequencing.

RESULTS

A total of 3517 children were included in the study. SARS-CoV-2 was detected in samples from 265 children (7.5%). SARS-CoV-2 infected patients were younger than those without SARS-CoV-2 infection (median age: 6 versus 12 months, p < 0.0001). The majority of infections (61.5%) were associated with the Omicron variant. The median weekly SARS-CoV-2 positivity rate ranged from 1.76% during the Alpha variant wave to 24.5% with the emergence of the Omicron variant. Most children (70.2%) were treated as outpatients, and seventeen patients were admitted to the intensive care unit. Other respiratory viruses were more frequently detected in SARS-CoV-2 negative children than in positive ones (82.1% versus 37.4%, p < 0.0001). Human rhinovirus/enterovirus and respiratory syncytial virus were the most prevalent in both groups.

CONCLUSIONS

We observed a low prevalence of SARS-CoV-2 infection in children attending pediatric ED, despite the significant increase due to Delta and Omicron variants, and an important circulation of other respiratory viruses. Severe disease was overall rare in children.

[Virological diagnosis of lower respiratory tract infections]

INTRODUCTION

The etiological diagnosis of bronchopulmonary infections cannot be assessed with clinical, radiological and epidemiological data alone. Viruses have been demonstrated to cause a large proportion of these infections, both in children and adults.

BACKGROUND

The diagnosis of viral bronchopulmonary infections is based on the analysis of secretions, collected from the lower respiratory tract when possible, by techniques that detect either influenza and respiratory syncytial viruses, or a large panel of viruses that can be responsible for respiratory disease. The latter, called multiplex PCR assays, allow a syndromic approach to respiratory infection. Their high cost for the laboratory raises the question of their place in the management of patients in terms of antibiotic economy and isolation. In the absence of clear recommendations, the strategy and equipment are very unevenly distributed in France.

OUTLOOK

Medico-economic analyses need to be performed in France to evaluate the place of these tests in the management of patients. The evaluation of the role of the different viruses often detected in co-infection, especially in children, also deserves the attention of virologists and clinicians.

CONCLUSIONS

The availability of new diagnostic technologies, the recent emergence of SARS-CoV-2, together with the availability of new antiviral drugs are likely to impact future recommendations for the management of viral bronchopulmonary infections.

Novel Use of Rapid Antigen Influenza Testing in the Outpatient Setting To Provide an Early Warning Sign of Influenza Activity in the Emergency Departments of an Integrated Health System

Seasonal influenza virus is associated with high morbidity and mortality especially in vulnerable patient populations. Here, we demonstrate the novel use of Sofia influenza A+B fluorescent immunoassay (FIA), a rapid antigen-based influenza point-of-care test (POCT), combined with Virena software for automatic deidentified tracking of influenza activity across the Los Angeles area and for predicting surges of influenza cases in the emergency department (ED). We divided outpatient clinics into 6 geographic zones and compared weekly influenza activity. In the outpatient setting, there were 1,666 and 274 influenza A and influenza B positives, respectively, across the 2018 to 2019 influenza season and 1,857 and 1,449 influenza A and influenza B positives, respectively, during the 2019 to 2020 influenza season, with zone-specific differences observed. Moreover, we found that a rapid increase in outpatient influenza was followed by an influx in influenza-positive cases in the ED, offering a 1- to 3-week warning sign for ED influx of triple or quadruple the number of influenza cases compared to the prior week. Sofia influenza A+B FIA allows for surveillance of real-time deidentified influenza activity. Tracking of such data may serve as a valuable region-specific influenza indicator and predictor to guide infection prevention measures in both the outpatient and hospital settings. High-impact interventions include designating areas for waiting rooms for influenza-like illnesses, altering staff scheduling in anticipation of surges, and securing sufficient personal protective equipment and antivirals during the height of influenza season.

Rapid influenza diagnostic test at triage can decrease emergency department length of stay

OBJECTIVE

Even if performing rapid influenza diagnostic tests test will not change clinical decision making, we sometimes perform at triage to reduce length of stay in Japan. Whether performing rapid influenza diagnostic tests at triage may shorten emergency department (ED) length of stay (LOS) is remains unclear. We aimed to determine the utility of rapid influenza diagnostic tests at triage in shortening ED length of stay LOS.

METHODS

We retrospectively reviewed medical records of patients discharged from our ED after receiving results from rapid influenza diagnostic tests during the influenza season from December, 2013 to March, 2019. Eligibility criteria were a walk-in visit, age ≥15 years, triage performed, rapid influenza diagnostic test administered, and no admission. The triage group received rapid influenza diagnostic tests at triage. The after-examination group received their tests only after examination by a doctor. The primary outcome was ED LOS after propensity score matching to adjust for several covariates.

RESULTS

Of 2,768 eligible patients, 2,554 patients were enrolled in the triage group (n = 363) or after examination group (n = 2,191). There were 329 matched pairs after propensity score matching. Median ED LOS was significantly shorter in the triage group than in the after-examination group after propensity score matching (81 min (interquartile range [IQR] 60 to 111) vs 106 min (IQR 80-142); median difference 24 min (95% confidence interval 17-30)).

CONCLUSIONS

Performing rapid influenza diagnostic tests at triage was associated with shorter ED LOS during the influenza season.

The Importance of Rapid Influenza Testing in Pediatric Primary Care: Experience During Three Consecutive Influenza Seasons (2016-2019) in Barcelona (Catalonia, Spain)

Clinical diagnosis of influenza has low sensitivity in infants and children. Signs and symptoms are non-specific and similar to those of other respiratory viruses. Rapid influenza diagnostic tests (RIDTs) with adequate sensitivity and specificity used at the point of care can be useful for an etiologic diagnosis of influenza in primary care. This should have an impact on better management of these patients. We conducted a study during three consecutive influenza seasons (2016-2017, 2017-2018, and 2018-2019) in pediatric primary care settings collecting data from influenza point-of-care tests (POCTs)-confirmed ≤ 6-year-old patients. During the first two influenza seasons, antibiotic prescriptions and additional visits from influenza POCT-confirmed patients (Group_1) were compared to patients with influenza-like illness (ILI) (Group_2), or fever (2016 ICD-10 code R50) with no other signs of influenza (Group_3). Group_1 had 0.19 (2016-2017) and 0.23 (2017-2018) additional visits compared to 0.48 (2016-2017) and 0.49 (2017-2018) Group_2 p < 0.001 and 1.01 (2016-2017) and 0.80 (2017-2018) Group_3 p < 0.001. Antibiotic prescription was lower in Group_1 (10.2%) vs. Group_3 (17.2%) p < 0.002, difference statistically significant only for the 2017-2018 season. During the third season (2018-2019), RIDTs results were transmitted in real time to the reference laboratory ia the cloud, which strengthens the monitoring of circulating influenza viruses in the community. In our experience, the use of POCTs has a great potential in primary care specially in infants and young children in which the diagnosis maybe missed due to non-specific signs and symptoms.