Cloud-Based Influenza Surveillance System in Emergency Departments Using Molecular-Based Testing: Advances and Challenges.

INTRODUCTION: Electronic influenza surveillance systems aid in health surveillance and clinical decision-making within the emergency department (ED). While major advances have been made in integrating clinical decision-making tools within the electronic health record (EHR), tools for sharing surveillance data are often piecemeal, with the need for data downloads and manual uploads to shared servers, delaying time from data acquisition to end-user. Real-time surveillance can help both clinicians and public health professionals recognize circulating influenza earlier in the season and provide ongoing situational awareness. METHODS: We created a prototype, cloud-based, real-time reporting system in two large, academically affiliated EDs that streamed continuous data on a web-based dashboard within hours of specimen collection during the influenza season. Data included influenza test results (positive or negative) coupled with test date, test instrument geolocation, and basic patient demographics. The system provided immediate reporting to frontline clinicians and to local, state, and federal health department partners. RESULTS: We describe the process, infrastructure requirements, and challenges of developing and implementing the prototype system. Key process-related requirements for system development included merging data from the molecular test (GeneXpert) with the hospitals' EHRs, securing data, authorizing/authenticating users, and providing permissions for data access refining visualizations for end-users. CONCLUSION: In this case study, we effectively integrated multiple data systems at four distinct hospital EDs, relaying data in near real time to hospital-based staff and local and national public health entities, to provide laboratory-confirmed influenza test results during the 2014-2015 influenza season. Future innovations need to focus on integrating the dashboard within the EHR and clinical decision tools.

Monitoring influenza virus susceptibility to oseltamivir using a new rapid assay, iART.

A new rapid assay for detecting oseltamivir resistance in influenza virus, iART, was used to test 149 clinical specimens. Results were obtained for 132, with iART indicating 41 as 'resistant'. For these, sequence analysis found known and suspected markers of oseltamivir resistance, while no such markers were detected for the remaining 91 samples. Viruses isolated from the 41 specimens showed reduced or highly reduced inhibition by neuraminidase inhibition assay. iART may facilitate broader antiviral resistance testing.

Simulated Respiratory Secretion for Use in the Development of Influenza Diagnostic Assays.

Many assays have been developed for the detection of influenza virus which is an important respiratory pathogen. Development of these assays commonly involves the use of human clinical samples for validation of their performance. However, clinical samples can be difficult to obtain, deteriorate over time, and be inconsistent in composition. The goal of this study was to develop a simulated respiratory secretion (SRS) that could act as a surrogate for clinical samples. To this end, we determined the effects major respiratory secretion components (Na+, K+, Ca2+, cells, albumin IgG, IgM, and mucin) have on the performance of influenza assays including both nucleic acid amplification and rapid antigen assays. Minimal effects on the molecular assays were observed for all of the components tested, except for serum derived human IgG, which suppressed the signal of the rapid antigen assays. Using dot blots we were able to show anti-influenza nucleoprotein IgG antibodies are common in human respiratory samples. We composed a SRS that contained mid-point levels of human respiratory sample components and studied its effect compared to phosphate buffered saline and virus negative clinical sample matrix on the Veritor, Sofia, CDC RT-PCR, Simplexa, cobas Liat, and Alere i influenza assays. Our results demonstrated that a SRS can interact with a variety of test methods in a similar manner to clinical samples with a similar impact on test performance.

Analytical reactivity of 13 commercially available rapid influenza diagnostic tests with H3N2v and recently circulating influenza viruses.

OBJECTIVES: Rapid influenza diagnostic tests (RIDTs) used widely in clinical practice are simple to use and provide results within 15 minutes; however, reported performance is variable, which causes concern when novel or variant viruses emerge. This study's goal was to assess the analytical reactivity of 13 RIDTs with recently circulating seasonal and H3N2v influenza viruses, using three different viral measures. DESIGN: Virus stocks were characterized by infectious dose (ID50 ) and nucleoprotein (NP) concentration, diluted at half-log dilutions, and tested with each RIDT and real-time RT-PCR. RESULTS: Strong correlation was observed between NP concentration and RIDT reactivity; however, only weak correlation was seen with ID50 or Ct values. Only four RIDTs detected viral NP at the lowest dilution for all influenza A viruses (IAV). Influenza A viruses not detected by more than one RIDT had lower NP levels. Of the 13 RIDTs, 9 had no significant differences in reactivity across IAV when compared to NP levels. CONCLUSIONS: Previous reports of RIDT performance typically compare reactivity based on ID50 titers, which in this study correlated only weakly with proportional amounts of viral NP in prepared virus samples. In the context of the strong correlation of RIDT reactivity with NP concentration, H3N2v was found to be as reactive as seasonal circulating IAV. While these findings may not reflect clinical performance of these RIDTs, measuring NP concentration can be useful in the future to assess comparable reactivity of available RIDTs, or to assess reactivity with newly evolving or emerging viruses.

Validation of a method for preparing influenza H5N1 simulated samples.

Avian influenza virus type A subtype H5N1 and potentially other novel influenza A viruses continue to pose a concern with mutation into a form easily transmitted between humans. The ability to rapidly detect and characterize influenza viruses, and distinguish seasonal and novel influenza A viruses such as H5N1, remains important to minimize morbidity and mortality in humans. As with other rare and emerging viral pathogens, clinical specimens from persons with H5N1 infections are extremely rare. Consequently, development of standardized methods and accepted criteria are necessary for both ensuring the validity of available diagnostic methods and for assessing the potential of new diagnostic tests that can detect and differentiate H5N1 and other novel influenza A viruses. Additionally, genotypic and antigenic evolution of H5N1 poses a challenge with maintaining updated reference virus strains. In this report, a method for preparing simulated samples using defined procedures and carefully selected H5N1 virus strains is described, and the reliability for using these samples in an evaluation protocol with a laboratory test for differentiating H5N1 virus from other influenza A viruses is evaluated.