CPC-Containing Mouthwash Can Inactivate the Coronavirus in 30 Seconds
New in vitro test results released by SUNSTAR show that, within 30 seconds of exposure, mouthwash containing CPC effectively reduces the coronavirus viral load by 99,9%.
In the SUNSTAR experiment, mouthrinse containing CPC was mixed with a solution containing the coronavirus (SARS-CoV-2) and incubated for 30 seconds in a lab. After this, researchers measured the reduction in viral load. All CPC-containing mouthrinses tested, containing 0,04% to 0,3% CPC concentration, directly and significantly reduced the viral load by more than 99,9% .
While further experiments are needed to replicate these results in humans, these newly released test results suggest that using existing CPC-containing mouthwashes has the potential to become an important element in our fight to protect against the coronavirus, along with all the recommended precautions, namely hand sanitising, social distancing and consistent mask use.
In other words, do you currently use hand sanitiser to kill the coronavirus on your hands? You could now potentially use CPC-containing mouthrinse as a way of sanitising your mouth.
Is oral hygiene really relevant to COVID-19?
Yes, as it turns out, our mouths are an unexpected repository for the coronavirus. How can this be – isn’t the coronavirus expected to colonise our respiratory system? That’s what we’ve always heard… Well, here is the newly uncovered story.
Coronavirus, as we all know by now, comes with spikes. It is called “corona” (“crown” in Latin) exactly because of its many spikes, made of lipid (fat)-containing proteins known as oligosaccharide chains.
It turns out these spikes have an unwelcome function! They are able to attach to or “land” on any of our cells that have an « ACE2 » receptor, which you can think of as a landing station for the virus. This means that the coronavirus can enter any cell in our body that has an ACE2 receptor landing station.
Once the virus has entered the cell, it uses it as a factory to replicate itself as much as possible. When the virus concentration is high enough, the cell bursts and releases new copies of the viruses that can infect other healthy cells.
As it turns out, scientists have recently determined that we have a lot of ACE2 receptors in our mouths, specifically on the tongue . This makes our mouth a good location for the accumulation of the coronavirus. Once the coronavirus has settled and replicated in the mouth, saliva droplets become vectors of transmission of the virus.
So the coronavirus is present in the mouth of COVID-19 patients?
The answer is yes – the virus isn’t just in your nose and lungs. We have ACE2 receptors in our mouth, so the virus can settle there.
Scientists at Yale measured the coronavirus genetic material known as RNA (Ribonucleic acid) in the saliva of COVID-19 patients. They detected even more coronavirus RNA in the saliva than in nasopharyngeal (nasal) swabs: 1 millilitre of saliva contains some 385'000 copies of coronavirus RNA .
So what is this CPC that inactivates the coronavirus?
Fortunately, CPC-containing mouthwashes can inactivate the coronavirus in our oral cavity in just 30 seconds of exposure. CPC, short for “Cetylpyridinium chloride” is an antimicrobial compound which has been used in mouthwashes for decades.
It is reassuring to know that CPC has a history of 30 years of safe use in mouthwashes, helping to reduce gingivitis and prevent dental plaque by killing bacteria and other microorganisms .
What we did not know until recently is that, in a lab setting, it can inactivate viruses such as the coronavirus which causes COVID-19 and that it can act very quickly, within 30 seconds of exposure. This is how it works.
The coronavirus we hve all been talking about has its entire surface covered in spikes which act as a lipid (fat) envelope . Well this is the good news: CPC works by breaking down the coronavirus protective shield – it breaks down those scary spikes that give it its “corona” name.
Light at the end of the tunnel?
There is hope that the end of this pandemic is in sight – vaccine candidates show positive results and have been approved. Yet, we have been told that we need to continue to take precautionary measures because vaccines will take time to reach everyone and because we have learned that animal-derived viruses can spread more easily than we thought. New habits are likely to stay, especially easy ones such as hand sanitising, and who knows, mouth sanitising too?
By potentially limiting the viral load in the oral cavity, CPC-containing mouthwash can become an important addition to our fight against coronaviruses, alongside hand sanitising, social distancing and consistent mask use, as recommended by health authorities.
In summary, the good news is that CPC-containing mouthrinses have the potential to help us fight the coronavirus and that, like anything which keeps the virus at bay, is highly welcome!
 QTEC Report to Sunstar Inc. November 2020
 Xu Hao, Zhong Liang et al « High expression of ACE2 receptor of 2019-nCoV on the epithelial cells of oral mucosa” International Journal of Oral Science, 24 Feb 2020.
 Wyllie AL, Moore AJ et al.”Saliva or Nasopharyngeal Swab Specimens for Detection of SARS-CoV-2. N Engl J Med.2020”
 James P, Worthington HV, Parnell C, et al. Chlorhexidine mouthrinse as an adjunctive treatment for gingival health. Cochrane Database Syst Rev. 2017;3(3):CD008676. Published 2017 Mar 31. doi:10.1002/14651858.CD008676.pub2
 Herrera D, Serrano J, RoldánS, Sanz M. Is the oral cavity relevant in SARS-CoV-2 pandemic?. Clinical oral investigations. Aug;24(8):2925-30 2020.