A recent study published in Scientific Reports has demonstrated the antiviral effectiveness of cetylpyridinium chloride against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Cetylpyridinium chloride is an ammonium compound commonly present in mouthwash.
Background
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative pathogen of coronavirus disease 2019 (COVID-19) pandemic, is an enveloped, positive-sense, single-stranded RNA virus belonging to the human betacoronavirus family. The virus and its more aggressive variants have caused unprecedented damage to the global healthcare system, with more than 590 million confirmed infections and over 6.4 million deaths.
The primary entry site of SARS-CoV-2 into the human body is the respiratory epithelium, which expresses high levels of the entry receptor angiotensin-converting enzyme 2 (ACE2). Evidence indicates that the virus can replicate in the oral cavity and release into saliva. The literature has also established an association between salivary content of SARS-CoV-2 and COVID-19 aggravation.
Considering the significance of oral hygiene in the context of SARS-CoV-2 infection, scientists in the current study have investigated the antiviral effect as well as the mode of action of cetylpyridinium chloride against SARS-CoV-2 infection.
Cetylpyridinium chloride is an antimicrobial compound widely used in mouthwash to prevent bacterial, fungal, or viral infections in the oral cavity. The compound is known to exert antimicrobial effects by disrupting lipid membrane via physicochemical interactions. A few studies have indicated that cetylpyridinium chloride is effective against wild-type SARS-CoV-2 at low concentrations (10–50 µg/ml).
Impact of cetylpyridinium chloride on SARS-CoV-2 infectivity
The study examined the antiviral effect of cetylpyridinium chloride on a range of SARS-CoV-2 strains, including wild-type SARS-CoV-2 and alpha, beta, and gamma variants. The plaque assay was conducted to examine viral infectivity in the presence and absence of the compound.
The findings revealed that cetylpyridinium chloride at low concentrations (5 – 40 µg/ml) significantly suppresses the infectivity of all tested SARS-CoV-2 strains in a dose-dependent manner. The tested concentrations were lower than that used in commercially available mouthwash (50 µg/ml).
Impact of cetylpyridinium chloride on viral entry
The findings revealed that cetylpyridinium chloride significantly reduces the expression and copy number of viral RNA in a dose-dependent manner. These findings indicate that cetylpyridinium chloride reduces the amount of infectious virus before host cell entry.
Antiviral activity of cetylpyridinium chloride in saliva
Human saliva is highly viscous and contains many proteins that may interfere with the antiviral efficacy of cetylpyridinium chloride. Saliva samples collected from healthy donors were mixed with the virus and cetylpyridinium chloride to determine the antiviral efficacy of the compound in saliva.
The findings revealed that cetylpyridinium chloride significantly suppresses viral infectivity even in saliva in a dose-dependent manner.
Antiviral mode of action of cetylpyridinium chloride
Cetylpyridinium chloride-treated SARS-CoV-2 was subjected to sucrose density analysis and transmission electron microscopy to determine the impact of cetylpyridinium chloride on viral morphology.
The findings revealed that cetylpyridinium chloride does not impact the overall structure of the virus. The spherical particle structure of SARS-CoV-2 remained unchanged after cetylpyridinium chloride treatment.
Study significance
The study highlights the potency of cetylpyridinium chloride in inhibiting SARS-CoV-2 and its variants even at low concentrations. The antiviral activity of the compound remains unchanged in human saliva.
The study has tested the antiviral efficacy of a commercial mouthwash that contains a similar concentration of cetylpyridinium chloride as used in the study. The mouthwash exhibits similar or even better antiviral efficacy than pure cetylpyridinium chloride solution. This indicates that the other ingredients present in the mouthwash do not interfere with the anti-SARS-CoV-2 activity of cetylpyridinium chloride.
Regarding mode of action, the study suggests that cetylpyridinium chloride exerts anti-SARS-CoV-2 activity most probably by denaturing viral proteins and not by disrupting lipid membrane.
Overall, the study indicates that cetylpyridinium chloride-containing products can be used as a preventive measure to reduce the transmission rate and progression of SARS-CoV-2 infection.
An ongoing clinical study is examining the effect of cetylpyridinium chloride on SARS-CoV-2 viral load in the saliva of COVID-19 patients.
News
Scientists Unlock a New Way to Hear the Brain’s Hidden Language
Scientists can finally hear the brain’s quietest messages—unlocking the hidden code behind how neurons think, decide, and remember. Scientists have created a new protein that can capture the incoming chemical signals received by brain [...]
Does being infected or vaccinated first influence COVID-19 immunity?
A new study analyzing the immune response to COVID-19 in a Catalan cohort of health workers sheds light on an important question: does it matter whether a person was first infected or first vaccinated? [...]
We May Never Know if AI Is Conscious, Says Cambridge Philosopher
As claims about conscious AI grow louder, a Cambridge philosopher argues that we lack the evidence to know whether machines can truly be conscious, let alone morally significant. A philosopher at the University of [...]
AI Helped Scientists Stop a Virus With One Tiny Change
Using AI, researchers identified one tiny molecular interaction that viruses need to infect cells. Disrupting it stopped the virus before infection could begin. Washington State University scientists have uncovered a method to interfere with a key [...]
Deadly Hospital Fungus May Finally Have a Weakness
A deadly, drug-resistant hospital fungus may finally have a weakness—and scientists think they’ve found it. Researchers have identified a genetic process that could open the door to new treatments for a dangerous fungal infection [...]
Fever-Proof Bird Flu Variant Could Fuel the Next Pandemic
Bird flu viruses present a significant risk to humans because they can continue replicating at temperatures higher than a typical fever. Fever is one of the body’s main tools for slowing or stopping viral [...]
What could the future of nanoscience look like?
Society has a lot to thank for nanoscience. From improved health monitoring to reducing the size of electronics, scientists’ ability to delve deeper and better understand chemistry at the nanoscale has opened up numerous [...]
Scientists Melt Cancer’s Hidden “Power Hubs” and Stop Tumor Growth
Researchers discovered that in a rare kidney cancer, RNA builds droplet-like hubs that act as growth control centers inside tumor cells. By engineering a molecular switch to dissolve these hubs, they were able to halt cancer [...]
Platelet-inspired nanoparticles could improve treatment of inflammatory diseases
Scientists have developed platelet-inspired nanoparticles that deliver anti-inflammatory drugs directly to brain-computer interface implants, doubling their effectiveness. Scientists have found a way to improve the performance of brain-computer interface (BCI) electrodes by delivering anti-inflammatory drugs directly [...]
After 150 years, a new chapter in cancer therapy is finally beginning
For decades, researchers have been looking for ways to destroy cancer cells in a targeted manner without further weakening the body. But for many patients whose immune system is severely impaired by chemotherapy or radiation, [...]
Older chemical libraries show promise for fighting resistant strains of COVID-19 virus
SARS‑CoV‑2, the virus that causes COVID-19, continues to mutate, with some newer strains becoming less responsive to current antiviral treatments like Paxlovid. Now, University of California San Diego scientists and an international team of [...]
Lower doses of immunotherapy for skin cancer give better results, study suggests
According to a new study, lower doses of approved immunotherapy for malignant melanoma can give better results against tumors, while reducing side effects. This is reported by researchers at Karolinska Institutet in the Journal of the National [...]
Researchers highlight five pathways through which microplastics can harm the brain
Microplastics could be fueling neurodegenerative diseases like Alzheimer's and Parkinson's, with a new study highlighting five ways microplastics can trigger inflammation and damage in the brain. More than 57 million people live with dementia, [...]
Tiny Metal Nanodots Obliterate Cancer Cells While Largely Sparing Healthy Tissue
Scientists have developed tiny metal-oxide particles that push cancer cells past their stress limits while sparing healthy tissue. An international team led by RMIT University has developed tiny particles called nanodots, crafted from a metallic compound, [...]
Gold Nanoclusters Could Supercharge Quantum Computers
Researchers found that gold “super atoms” can behave like the atoms in top-tier quantum systems—only far easier to scale. These tiny clusters can be customized at the molecular level, offering a powerful, tunable foundation [...]
A single shot of HPV vaccine may be enough to fight cervical cancer, study finds
WASHINGTON -- A single HPV vaccination appears just as effective as two doses at preventing the viral infection that causes cervical cancer, researchers reported Wednesday. HPV, or human papillomavirus, is very common and spread [...]
