Routine use of rapid respiratory virus testing in the emergency department (ED) appears to show limited benefit among patients with signs and symptoms of acute respiratory infection (ARI), according to a new study.
Rapid viral testing wasn’t associated with reduced antibiotic use, ED length of stay, or rates of ED return visits or hospitalization. However, testing was associated with a small increase in antiviral prescriptions and a small reduction in blood tests and chest x-rays.
“Our interest in studying the benefits of rapid viral testing in emergency departments comes from a commitment to diagnostic stewardship — ensuring that the right tests are administered to the right patients at the right time while also curbing overuse,” said lead author Tilmann Schober, MD, a resident in pediatric infectious disease at McGill University and Montreal Children’s Hospital.
“Following the SARS-CoV-2 pandemic, we have seen a surge in the availability of rapid viral testing, including molecular multiplex panels,” he said. “However, the actual impact of these advancements on patient care in the ED remains uncertain.”
The study was published online on March 4, 2024, in JAMA Internal Medicine).
Rapid Viral Testing
Dr. Schober and colleagues conducted a systematic review and meta-analysis of 11 randomized clinical trials to understand whether rapid testing for respiratory viruses was associated with patient treatment in the ED.
In particular, the research team looked at whether testing in patients with suspected ARI was associated with decreased antibiotic use, ancillary tests, ED length of stay, ED return visits, hospitalization, and increased influenza antiviral treatment.
Among the trials, seven studies included molecular testing, and eight used multiplex panels, including influenza and respiratory syncytial virus (RSV), influenza/RSV/adenovirus/parainfluenza, or a panel of 15 or more respiratory viruses. No study evaluated testing for SARS-CoV-2. The research team reported risk ratios (RRs) and risk difference estimates.
In general, routine rapid viral testing was associated with higher use of influenza antivirals (RR, 1.33) and lower use of chest radiography (RR, 0.88) and blood tests (RR, 0.81). However, the magnitude of these effects was small. For instance, to achieve one additional viral prescription, 70 patients would need to be tested, and to save one x-ray, 30 patients would need to be tested.
“This suggests that, while statistically significant, the practical impact of these secondary outcomes may not justify the extensive effort and resources involved in widespread testing,” Dr. Schober said.
In addition, there was no association between rapid testing and antibiotic use (RR, 0.99), urine testing (RR, 0.95), ED length of stay (0 h), return visits (RR, 0.93), or hospitalization (RR, 1.01).
Notably, there was no association between rapid viral testing and antibiotic use in any prespecified subgroup based on age, test method, publication date, number of viral targets, risk of bias, or industry funding, the authors said. They concluded that rapid virus testing should be reserved for patients for whom the testing will change treatment, such as high-risk patients or those with severe disease.
“It’s crucial to note that our study specifically evaluated the impact of systematic testing of patients with signs and symptoms of acute respiratory infection. Our findings do not advocate against rapid respiratory virus testing in general,” Dr. Schober said. “There is well-established evidence supporting the benefits of viral testing in certain contexts, such as hospitalized patients, to guide infection control practices or in specific high-risk populations.”