Point of Care Diagnostic Test for Influenza, Transforming Pathways in a UK Medical Assessment Suite (MAS).
The key to effective influenza (flu) management is time – the quicker the presence or absence of flu can be confirmed, the quicker anti-viral medication may be administered, and the quicker patients may be isolated to prevent transmission to others. Patients presenting to hospital emergency departments with suspected flu will typically have a nose or throat swab taken for diagnostic testing using real-time polymerase-chain-reaction (PCR). These test results can take over 24 hours to generate in hospitals where on-site testing is available.
During the 2014-2015 winter season, the NIHR Diagnostic Evidence Co-operative (DEC) Newcastle and the Royal Victoria Infirmary of Newcastle upon Tyne Hospitals NHS Foundation Trust joined forces with the Royal Hallamshire Hospital and Northern General Hospital of Sheffield Teaching Hospitals NHS Foundation Trust, to conduct a diagnostic accuracy study of the Alere™-i Influenza A & B Near Patient Test (NPT), in comparison to laboratory real-time PCR.
The DEC Newcastle worked with the study team from Sheffield Teaching Hospitals NHS Foundation Trust to calculate the comparative accuracy of the Alere™ i NPT. In addition to this, the DEC Newcastle used data collected relating to the use of isolation resources, antivirals and antibiotics during the study to inform a budget impact model, highlighting key benefits to NHS Trusts of the implementation of near patient testing for influenza.
During the study, 75% of patients who tested positive for influenza were not isolated, whilst 69% of isolated participants tested negative for influenza. Rapid point of care tests for influenza have the potential to lead to a more evidence based, and therefore more appropriate, use of isolation resource. This was reiterated through the economic analysis conducted by the DEC Newcastle, where the potential for substantial savings to be made for NHS Trusts, was demonstrated. This is particularly the case for NHS Trusts with off-site laboratories, where the time to actionable results can be longer.
Point of care testing has enabled us to diagnose influenza (flu) rapidly in patients presenting to medical admissions and A+E with flu-like symptoms. This has transformed our ability to diagnose influenza rapidly such that we can prevent admissions and isolate and treat those who need admission, early. It has been vital as part of our sepsis screening to give an early definitive diagnosis of influenza in patients presenting with signs of possible sepsis.
Dr Ashley Price, Consultant in Infectious Diseases
Patients presenting at A+E departments with influenza present a transmission risk to both healthcare professionals and other patients. The spread of influenza can happen quickly and easily in a confined environment, and to vulnerable groups such as the young, frail and elderly, contracting flu can significantly increase morbidity and mortality. Having a test which can rapidly detect whether influenza is present can help staff promptly initiate infection control procedures, including isolation.
Alere™ i Influenza A & B Near Patient Test (NPT), a rapid point of care test for flu A & B, was recently evaluated in four UK hospitals. Although similar products have emerged on the market, this was, to the best of our knowledge, the first clinical evaluation that considered the benefits (and harms) of use within UK NHS Trusts.
The Alere™ i Influenza A & B Near Patient Test uses isothermal nicking-enzyme amplification technology (NEAR) to provide a result within fifteen minutes.
- A diagnostic study in comparison to laboratory real-time PCR has taken place
- The comparative accuracy has been calculated
- A budget impact model has been produced using data from the study
- The Alere™ i Influenza A & B point of care test is now in routine use in two of the study sites (Sheffield Royal Hallamshire Hospital and Doncaster Royal Infirmary).
- In 2016 ahead of the winter flu season, the Medical Assessment Suite in the Royal Victoria Infirmary initiated the use of an alternative product – the Cephid Xpert® Xpress Flu point of care test for Influenza A and Influenza B.
Outcome/Impact
As the graph below indicates, initiation of the influenza Point of Care Test (POCT) led to a significant increase in the identification of patients with influenza.
Figure 1 Weekly number of patients with flu A&B admitted to Newcastle upon Tyne Hospitals Foundation Trust per winter flu season. The POCT for flu was initiated in between Winter 15/16 and Winter 16/17.
This intelligence has led to early treatment and isolation where possible. A significant proportion of patients with possible sepsis are identified as having influenza, leading to early discharge with a definite diagnosis of influenza. It is likely that in hospital, transmission has been reduced with prophylaxis of contacts and early isolation.
Use of the POCT for influenza within The Newcastle Upon Tyne Hospitals NHS Foundation Trust (NuTH) has transformed pathways for patients with suspected influenza and given quick results to rule out when influenza is not the cause of illness. This ensures that clinicians can initiate other, appropriate clinical investigations where necessary, and isolation facilities can be used for competing reasons.
Benefit
Detecting the presence of flu and thus taking measures to limit its spread has several benefits:
- Cost savings for NHS
- Prompt diagnostic decision
- Patients receive appropriate care quickly
- HCPs can promptly initiate the use of infection control procedures including isolation for patients testing positive for Influenza A and B
- HCPs can initiate prompt administration of anti-virals for those with influenza.
Health and Wellbeing
Funding and Efficiency
The AHSN NENC supported the DEC Newcastle, and now the MIC, both financially and in kind and also met with the Influenza POCT manufacturer, to provide advice on adoption and access strategies as well as commissioning pathways.
Other NHS Trusts considering use of the influenza POCT have been in contact for further details of this evaluation, which is an example of evidence generation for adoption, and which highlights the transferability of the work of the NIHR IVD Co-operative.
Start date: Evaluation started in 2014.
End date: Evaluation results published in 2017. POCT still in use in the Medical Assessment of NuTH.
Contact Details
NIHR In Vitro Diagnostics Co-operative: Dr Joy Allen, Senior IVD Evaluation Methodologist
AHSN: Donna Smith, Comms Team, AHSN NENC [email protected]
References
Reference to paper: https://www.ncbi.nlm.nih.gov/pubmed/28558954