The AV BreathTest™ is a drug/device combination for detecting and monitoring virulent lung infections - determining whether the cause is urease positive bacterial pathogens or a viral infection, the test can then guide appropriate use and selection of antibiotics.

It's based on the presence of the urease enzyme found in certain bacterial species that cause pneumonia, such as S. aureus, P. aeruginosa, Klebsiella and H. influenzae. Live urease-containing bacteria can be detected using inhaled ¹³C-urea which is converted by these bacteria to labelled carbon dioxide (¹³C0₂) and ammonia. The non-radioactive, isotopic ratio of ¹³C0₂ to naturally occurring ¹²C0₂ is measured in the exhaled breath of the patient and is akin to an infection thermometer for the lungs.