Diagnostic accuracy of point of care tests to distinguish between viral and bacterial infection for acute respiratory infection

In April 2023, we were commissioned to review the diagnostic test accuracy of near-patient, rapid tests to distinguish between bacterial and viral infection in suspected acute respiratory infection. This review was undertaken to inform NICE Guidance on Acute Respiratory Infection in over 16s: Initial assessment and management (GID-NG10376).

Respiratory infections are a common cause of illness. Healthcare professionals use clinical experience to decide whether an infection is caused by a virus or bacteria. However, this is not always easy to establish. We tried to identify how effective rapid tests are at distinguishing between viral and bacterial respiratory infections.  

Project status: completed

Contact: bristol-esg@bristol.ac.uk

What did we do? 

We carried out a systematic review to identify and summarize all the existing reviews and studies in this area.  We looked at a number of different tests which may be used to distinguish between bacterial and viral causes of respiratory infections. In particular, we assessed the following: 

  • the use of individual symptoms and signs (such as the presence of cough, or a fever)  
  • the use of combinations of symptoms and signs (the presence or absence of multiple symptoms) 
  • various ‘biomarker’ tests, which look at levels of certain substances in the blood, for example markers of inflammation 

We also looked at specific tests for ‘flu and respiratory syncytial virus (RSV), which are common causes of viral infection. 

What did we find? 

We found that symptoms and signs were not able to distinguish accurately between people with bacterial and viral causes of an infection. The accuracy of biomarker tests was slightly better, particularly when combinations of markers were used together. The accuracy of rapid tests for ‘flu and RSV varied considerably; the most accurate tests were those that detect viral genetic material. However, most of the evidence we identified was not robust. There were concerns about the conduct of some of the studies. In some cases there was uncertainty whether a test was really accurate enough to be useful. Therefore there is still doubt about whether any of these tests will be useful additions to current clinical care.  

Publication details:

Webster KE, Parkhouse TL, Dawson S, Jones HE, Brown EL, Hay AD, Whiting PF, Cabral CL, Caldwell DM & Higgins JPT. Diagnostic accuracy of point of care tests for acute respiratory infection: a systematic review of reviews. NIHR Health Technology Assessment. 2024. (Accepted/In press)

The NICE Guidance was released in October 2023 and is available from the NICE website: Project information | Acute Respiratory Infection in over 16s: Initial assessment and management | Guidance | NICE. The report produced by Bristol ESG for NICE is available as Evidence Review C from the Guideline pages: evidence-review-3 (nice.org.uk)