In preclinical studies, spray offered nearly 100% protection from respiratory infections by COVID-19, influenza, viruses, and pneumonia-causing bacteria

Most viruses enter our system through the nose. When we catch an airborne infection like the flu and COVID, we breathe out tiny droplets of fluids that contain the pathogen. Healthy people around us breathe in these pathogen-containing droplets, which attach inside their nose and infect the cells that line the nasal passageways. The pathogen replicates and can be released back into the air when an individual who is sick, whether they know it or not, sneezes, coughs, laughs, sings, or even just breathes.

Vaccines against these viruses can be beneficial, but they’re imperfect. Vaccinated people still get infected and spread the infection to others. Masks are also helpful but aren’t perfect, either — they can leak, and many people wear them improperly or choose not to wear them at all.