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Over the past year, we’ve all learned the drill for protecting ourselves and others from viral infections: wear a mask, take supplements to support immunity, practice social distancing, and wash your hands as often as possible. But another layer of safe, effective protection could be right under your nose.
New research suggests that nasal hygiene plays a significant role in preventing infection, and nasal sprays with specific active ingredients may reduce the risk of contracting SARS-CoV-2, the virus that causes Covid-19, and other viral invaders. Rather than mitigating symptoms or lessening severity, nasal sprays work prophylactically, helping to prevent infection altogether.
The nasal mucosa—the thin tissue lining the cavity of the nose—is the first barrier against inhaled substances, including foreign particles, allergens, bacteria, and viruses. In the case of SARS-CoV-2, research suggests that the nose is not only the entry site, but also the main target of the virus. The virus tends to become firmly established first in the nasal cavity, before progressing into the airway and lungs. And the nose has a higher viral load of SARS-CoV-2 than anywhere else in the body after infection.
Because the nose is the dominant site from which lung infections begin, good nasal hygiene is important. Emerging research suggests that sprays with ingredients that block adhesion of the virus and decrease viral load in the nose may be effective in both preventing transmission of SARS-CoV-2 and diminishing the severity of the disease in people who have been infected.
A number of trials are currently in progress. Some highlights:
Povidone-iodine—an antimicrobial agent with a long history of safe and effective use—may protect against Covid-19. Earlier research showed that povidone-iodine (PVP-I) mouthwashes and gargles significantly reduce viral load in the oral cavity, and other studies show that PVP-I may rapidly inactivate coronaviruses, including SARS and MERS. In one preliminary study, Halodine Nasal Antiseptic—a nasal spray containing povidone-iodine—appears to inactivate SARS-CoV-2 in as little as 15 seconds, even at concentrations as low as 0.5 percent.
Nitric oxide has long been used to treat a variety of bacterial, fungal, and viral diseases. Used as a nasal spray, nitric oxide may help protect against SARS-CoV-2 by destroying the virus and impeding viral replication within the cells in the nose. In preliminary tests, SaNOtize Nitric Oxide Nasal Spray (NONS)—a solution of nitric oxide—inactivated more than 99.9 percent of SARs-CoV-2. In separate animal studies, infected rodents showed a 95 percent drop in viral load within a day after infection, while half the rodents showed no detectable virus at all. Other research suggests that nitric oxide may also lessen the severity of symptoms in Covid-19 patients, and Phase II clinical trials of SaNOtize NONS are currently underway in Canada.
When it comes to avoiding viral infections, wash your nose, not just your hands
Focus on Xylitol
Research suggests that xylitol may play a significant role in both preventing and treating Covid-19. A naturally occurring sugar alcohol found in many fruits, vegetables, and other plants, xylitol has well-recognized antibacterial activities, and earlier studies show that it helps inhibit bacteria from sticking to tissue, allowing the body to wash pathogens away.
Now, studies suggest that xylitol may also have an anti-adherence effect on the SARS-CoV-2 virus, blocking receptor sites and inhibiting the virus from attaching to the cell walls of its host. In earlier research, xylitol showed antiviral activity against avian influenza virus (AIV), Newcastle disease virus (NDV), infectious bursal disease virus (IBDV), and other viruses.
Preliminary studies conducted at two different laboratories found a combination of xylitol and grapefruit seed extract (GSE) was effective against viral pathogens, including coronavirus. Research suggests that Xlear Nasal Spray, a combination of xylitol and GSE, can help block viral adhesion in the nose and help deactivate SARS-CoV-2. In one analysis, Xlear Nasal Spray destroyed 99.99 percent of the SARS-CoV-2 virus, and a 5-percent solution of xylitol reduced viral adhesion to an undetectable level.
The combination of xylitol and GSE may not only prevent, but also treat, Covid-19. In one case study, Covid-19 patients who used Xlear Nasal Spray showed reduced symptoms and rapid improvement and received a negative test 50 percent faster than average.
Practice Nasal Hygiene
The takeaway is pretty clear: when it comes to avoiding viral infections, wash your nose, not just your hands. While nasal sprays continue to be investigated for their role in preventing and treating Covid-19, cleansing your nose with a product that blocks viral adhesion and helps destroy the virus adds an important layer of protection. And while other nasal sprays aren’t currently available, Xlear Nasal Spray with xylitol and grapefruit seed extract is a safe, effective option for defensive nasal hygiene.