Sept. 29 (UPI) -- Researchers have developed a new nasal cleansing spray, featuring calcium-rich salts, that can kill sub-micron aerosolized particles, according to a study published Tuesday in the Molecular Frontiers Journal.
Scientists suggest the drug-free calcium-enriched nasal salts, called FEND, could be used to combat the spread of COVID-19.
To test the effectiveness of FEND, researchers at Harvard and MIT measured the number of exhaled aerosols of 76 volunteers who did not have COVID-19 before and after using the nasal saline.
The nasal cleansing solution, which features a mixture of calcium chloride and sodium chloride in distilled water, was created by scientists at Sensory Cloud, a Boston-based technology startup.
The saline solution is released as a mist by a nebulizer before being inhaled through the nostrils by users.
When researchers recorded aerosol measurements prior to the administration of FEND, they found a classic "super spreading" distribution among the volunteers -- 20 percent of the volunteers were found to generate 80 percent of exhaled aerosols.
According to researchers, many of these aerosols were the sub-micron aerosolized particles that aren't effectively filtered by most daily-use masks.
Among the super-spreaders, researchers found half were responsible for 80 percent of super-spreader aerosol production, or 64 percent of overall aerosol production -- super super-spreaders.
After FEND was inhaled by the volunteers, aerosols exhaled by the highest producing super-spreaders was suppressed by 84 percent. Scientists measures a 78 percent overall decline in aerosol production by all super-spreaders.
"The findings, which build on an earlier study this summer, suggest that we can provide what is, in effect, a nasal filter to protect at-risk populations from viral carrying aerosols," lead study author David Edwards, lead study author and founder Sensory Cloud.
"Access to a new hygiene protocol for reducing the spread of these smallest particles, which can otherwise be dispersed into indoor air and enter deep into our lungs, can be an important intervention as we head back to work and school, as winter approaches, and as troubling data about rates of infection continue to emerge," said Edwards, a professor at Harvard's John A. Paulson School of Engineering and founder of Sensory Cloud.
In a followup study, researchers tested the use of FEND among a quarantined family of four, featuring a COVID-positive mother.
Exhaled aerosols measured eight days after the onset of symptoms revealed extremely high output, but after FEND, the mother's exhaled aerosols declined to levels similar to those of COVID-negative test subjects.
Tests showed FEND's aerosol suppression effects lasted several hours after administration, researchers reported.
In a third study, researchers compared the effects of surgical masks and FEND use among a group of adults and children. When researchers excluded one outlier individual, they found exhaled aerosols were reduced by 59 percent by masks and 87 percent by FEND usage.
Researchers suggest FEND could be used in conjunction with masks or as another method of protection when masks are impractical.
"We continue to support human volunteer studies in the USA and overseas, exploring unique hygiene protocols for collaborative teams, and deepening our understanding of nasal salt hygiene among those infected with COVID-19," said Edwards.
"As FEND comes to market in coming weeks, we will prioritize distribution to healthcare professionals, and other essential workers in the USA and in countries around the world that are hardest hit by the COVID-19 pandemic," he said. "As we scale up production, we hope also to be helpful to clearing the air for children and teachers in public schools around the world."