New blood test to check antibiotic overuse

A new blood test can help cut down on unnecessary use of antibiotics by detecting within two hours if bacteria or virus is the source of an infection, scientists say.
A team of scientists from several medical centres in Israel, in collaboration with the company MeMed, developed the new test.
A large clinical study has validated the ability of the diagnostic blood test to determine whether a patient has an acute bacterial or viral infection.
Unlike most infectious disease diagnostics that rely on direct pathogen detection, the assay decodes the body's immune response to accurately characterise the cause of the infection.

Bacterial and viral infections are often clinically indistinguishable, leading to antibiotic overuse and contributing to the spread of antibiotic resistance.
The inability to rapidly differentiate infections also results in the underuse of antibiotics, estimated to occur in 20-40 per cent of all bacterial infections, putting patients at risk of complications and increasing healthcare costs.

"Antibiotic misuse is a pressing public health concern, with devastating healthcare and economic consequences," Eran Eden, CEO of MeMed, noted.
"Rapid, accurate and actionable diagnostic tools are an important part of the solution because they can aid physicians in making better informed treatment decisions," Eden said.

The technology leverages the fact that bacteria and viruses trigger different pathways in the immune system.
By conducting extensive screening of immune system proteins in patients with acute infections, researchers identified three soluble proteins that are uniquely activated by bacteria or viruses.
They then developed proprietary algorithms that integrate these proteins to produce an immune signature that accurately identifies the cause of infection.
"The ImmunoXpert immune signature was developed and independently validated on a cohort of 1,002 patients with acute infections and yielded highly accurate results, with sensitivity and specificity greater than 90 per cent," researchers said.
The assay was validated in a diverse group of paediatric and adult patients at different time points after the onset of symptoms (from the first day up to 12 days) and across 56 different pathogen species. ImmunoXpert remained robust over all sub-groups studied.

The predictive power of the assay's immune signature outperformed routine biomarker and laboratory tests, as well as combinations of these tests, researchers said.
The research was published in the journal PLOS ONE.