Evaluation of a fluorescent immunoassay rapid test (Sofia™) for detection of influenza A+B and RSV in a tertiary pediatric setting

Expert consensus on the diagnosis, treatment, and prevention of respiratory syncytial virus infections in children

BACKGROUND

Respiratory syncytial virus (RSV) is the leading global cause of respiratory infections and is responsible for about 3 million hospitalizations and more than 100,000 deaths annually in children younger than 5 years, representing a major global healthcare burden. There is a great unmet need for new agents and universal strategies to prevent RSV infections in early life. A multidisciplinary consensus development group comprising experts in epidemiology, infectious diseases, respiratory medicine, and methodology aims to develop the current consensus to address clinical issues of RSV infections in children.

DATA SOURCES

The evidence searches and reviews were conducted using electronic databases, including PubMed, Embase, Web of Science, and the Cochrane Library, using variations in terms for "respiratory syncytial virus", "RSV", "lower respiratory tract infection", "bronchiolitis", "acute", "viral pneumonia", "neonatal", "infant" "children", and "pediatric".

RESULTS

Evidence-based recommendations regarding diagnosis, treatment, and prevention were proposed with a high degree of consensus. Although supportive care remains the cornerstone for the management of RSV infections, new monoclonal antibodies, vaccines, drug therapies, and viral surveillance techniques are being rolled out.

CONCLUSIONS

This consensus, based on international and national scientific evidence, reinforces the current recommendations and integrates the recent advances for optimal care and prevention of RSV infections. Further improvements in the management of RSV infections will require generating the highest quality of evidence through rigorously designed studies that possess little bias and sufficient capacity to identify clinically meaningful end points.

Respiratory virus infections after allogeneic stem cell transplantation: Current understanding, knowledge gaps, and recent advances

Before the COVID-19 pandemic, common community-acquired seasonal respiratory viruses (CARVs) were a significant threat to the health and well-being of allogeneic hematopoietic cell transplant (allo-HCT) recipients, often resulting in severe illness and even death. The pandemic has further highlighted the significant risk that immunosuppressed patients, including allo-HCT recipients, face when infected with SARS-CoV-2. As preventive transmission measures are relaxed and CARVs circulate again among the community, including in allo-HSCT recipients, it is crucial to understand the current state of knowledge, gaps, and recent advances regarding CARV infection in allo-HCT recipients. Urgent research is needed to identify seasonal respiratory viruses as potential drivers for future pandemics.

Assessment of potential factors associated with the sensitivity and specificity of Sofia Influenza A+B Fluorescent Immunoassay in an ambulatory care setting

Background

Seasonal influenza leads to an increase in outpatient clinic visits. Timely, accurate, and affordable testing could facilitate improved treatment outcomes. Rapid influenza diagnostic tests (RIDTs) provide results in as little as 15 minutes and are relatively inexpensive, but have reduced sensitivity when compared to RT-PCR. The contributions of multiple factors related to test performance are not well defined for ambulatory care settings. We assessed clinical and laboratory factors that may affect the sensitivity and specificity of Sofia Influenza A+B Fluorescence Immunoassay.

Study design

We performed a post-hoc assessment of surveillance data amassed over seven years from five primary care clinics. We analyzed 4,475 paired RIDT and RT-PCR results from specimens collected from patients presenting with respiratory symptoms and examined eleven potential factors with additional sub-categories that could affect RIDT sensitivity.

Results

In an unadjusted analysis, greater sensitivity was associated with the presence of an influenza-like illness (ILI), no other virus detected, no seasonal influenza vaccination, younger age, lower cycle threshold value, fewer days since illness onset, nasal discharge, stuffy nose, and fever. After adjustment, presence of an ILI, younger age, fewer days from onset, no co-detection, and presence of a nasal discharge maintained significance.

Conclusion

Clinical and laboratory factors may affect RIDT sensitivity. Identifying potential factors during point-of-care testing could aid clinicians in appropriately interpreting negative influenza RIDT results.

Prognosis of hospitalized children under 2 years of age with co-detection of influenza A and respiratory syncytial virus at the healthcare facility

Abstract Objectives: the aim of this study is to evaluate the impact of co-detection of Flu A and RSV using rapid immunochromatographic tests at the point of care, in pediatric patients under 2 years of age in a general hospital. Methods: a retrospective cohort study was conducted to analyze clinical outcomes in hospitalized infants with viral respiratory disease with positive results of rapid immunochromatographic test for RSV and/or Flu-A, from 2013 to 2018. A logistic regression model was adjusted to analyze predictors of orotracheal intubation during hospitalization. Results: we analyzed 220 cases: RSV (192), Flu-A (9), co-detection (19). Lethality rate was 1.8% (2 cases), and 88% (194) were under 1 year of age. Mean time of hospitalizations was higher in patients with co-detection. Variables significantly associated with orotracheal intubation were: younger age in months, comorbidities, RSV and Flu-A co-detection, and bacterial pneumonia during hospitalization. Conclusions: RSV and Flu-Aco-detection was associated with the least favorable clinical prognoses in this study. Rapid test diagnosis may provide important information at the point of care, because molecular panels are not widely accessible in general hospitals. Rapid diagnosis allows timely evaluation and treatment.

Evaluation of a Commercial Colloidal Gold Assay for Detection of Influenza A and B Virus in Children's Respiratory Specimens

Objective: To evaluate the clinical diagnostic value of colloidal gold assay for detection of influenza A and B virus. Methods: Results were compared for colloidal gold assay for influenza antigen detection and real-time RT-PCR for RNA detection. Results: By performing the colloidal gold assay, the positive rate was 25.67% (105/409) for influenza A virus and 8.56% (35/409) for influenza B virus. While tested by real-time RT-PCR, 107(26.2%) were positive for influenza A virus and 35(8.6%) for influenza B virus. Using real-time RT-PCR as the gold standard, the sensitivity and specificity of the colloidal gold assay were 84.1% and 95.0%, respectively, for influenza A virus and 85.7% and 98.7% for influenza B virus. Conclusion: This colloidal gold assay may be one of the viable tools for the rapid screening for influenza viruses in an outpatient clinical practice.

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

OBJECTIVE

The objective of this study was to evaluate the impact of a rapid diagnostic test for influenza (the Sofia^® Influenza A+B FIA rapid diagnostic test [RDT]) in a pediatric emergency department (PED).

METHODS

A retrospective, observational, cross-sectional study was conducted in the PED of the Lille University Hospital between 2013 and 2015. All patients under 18 years of age for whom influenza RDT was administered were included. Clinical data, management, and related hospitalizations were compared between positive and negative RDT groups. The length of stay in the PED (main outcome) and the number of additional tests (biological and radiographic tests) between the two groups were compared.

RESULTS

A total of 238 tests were reported: 119 positive, 110 negative, nine invalid. The mean length of stay in the PED was significantly lower in the positive RDT group: 4.0h vs. 7.4h (P<10^-6). Patients with positive RDT had significantly fewer biological tests (20% vs. 56%; P<10^-7) and radiographs (23% vs. 52%; P<10^-5). The prevalence of hospitalizations in a short-stay unit was significantly lower in patients with positive RDT (0.8% vs. 9.1%; P=0.009).

CONCLUSIONS

This study showed a significant medical impact of the use of Sofia^® Influenza RDT A+B FIA in a PED regarding the length of stay and the number of additional explorations.

Detection Methods of Human and Animal Influenza Virus-Current Trends

The basic affairs connected to the influenza virus were reviewed in the article, highlighting the newest trends in its diagnostic methods. Awareness of the threat of influenza arises from its ability to spread and cause a pandemic. The undiagnosed and untreated viral infection can have a fatal effect on humans. Thus, the early detection seems pivotal for an accurate treatment, when vaccines and other contemporary prevention methods are not faultless. Public health is being attacked with influenza containing new genes from a genetic assortment between animals and humankind. Unfortunately, the population does not have immunity for mutant genes and is attacked in every viral outbreak season. For these reasons, fast and accurate devices are in high demand. As currently used methods like Rapid Influenza Diagnostic Tests lack specificity, time and cost-savings, new methods are being developed. In the article, various novel detection methods, such as electrical and optical were compared. Different viral elements used as detection targets and analysis parameters, such as sensitivity and specificity, were presented and discussed.

Diagnostic performance of the Sofia® influenza A+B fluorescent immunoassay in adult outpatients in Northern Taiwan

To evaluate the diagnostic performance of the Sofia influenza A+B fluorescent immunoassay (Sofia FIA), we performed a prospective study at the Chang Gung Memorial Hospital in Taiwan from January 2012 to December 2013. Patients who presented at out-patient clinics or the emergency department with influenza-like illness were included. Upper respiratory tract specimens were collected from oropharynx or nasopharynx. Performance of the Sofia FIA was compared to that of the Formosa One Sure Flu A/B Rapid Test. A Real-time reverse transcriptase-polymerase chain reaction assay (RT-PCR) and/or virus culture were used as reference standards. Of the 109 enrolled patients, the sensitivity, specificity, positive, and negative predictive values of the Sofia FIA to detect influenza A virus were 82%, 89%, 77%, and 89%, respectively. These parameters were 100% when the samples were from nasopharynx. The positive predictive value for influenza B virus detection was 29%. The sensitivity of the Sofia FIA for detection of influenza A virus was 93% between days 2 and 4 after onset of symptoms. For specimens with low viral loads (RT-PCR cycle threshold between 30 and 34.9), the sensitivity of The Sofia FIA was 83% (10/12). The Sofia FIA performed effectively in detecting influenza A virus infection. With nasopharyngeal samples, the performance was comparable to RT-PCR. Although influenza viral load typically decreases with time, the Sofia FIA was sensitive enough to identify influenza infecting patients presenting after several days of illness. However, a high false positive rate limits the assay's usefulness to identify influenza B virus infection.

Respiratory Syncytial Virus: Infection, Detection, and New Options for Prevention and Treatment

Respiratory syncytial virus (RSV) infection is a significant cause of hospitalization of children in North America and one of the leading causes of death of infants less than 1 year of age worldwide, second only to malaria. Despite its global impact on human health, there are relatively few therapeutic options available to prevent or treat RSV infection. Paradoxically, there is a very large volume of information that is constantly being refined on RSV replication, the mechanisms of RSV-induced pathology, and community transmission. Compounding the burden of acute RSV infections is the exacerbation of preexisting chronic airway diseases and the chronic sequelae of RSV infection. A mechanistic link is even starting to emerge between asthma and those who suffer severe RSV infection early in childhood. In this article, we discuss developments in the understanding of RSV replication, pathogenesis, diagnostics, and therapeutics. We attempt to reconcile the large body of information on RSV and why after many clinical trials there is still no efficacious RSV vaccine and few therapeutics.