People who come into contact with patients with 2019 coronavirus disease (COVID-19) are at high risk of being infected with its causative agent, Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2 ). Viral transmission in hospitals is of particular concern, as the close interaction between healthcare staff and patients contributes to the transmission of the virus – between them, their families and, subsequently, their communities.
Despite various public health interventions implemented, such as the adaptation of areas with negative atmospheric pressure, isolation areas for patients with COVID-19 and the mandatory use of personal protective equipment (PPE), controlling the spread of SARS-CoV-2 has had mixed results. In the absence of effective antiviral treatments, the current vaccination campaign is the main strategy across the world to prevent SARS-CoV-2.
In a recent study by a team of researchers in Mexico, Russia and Spain, silver nanoparticles (AgNP) inhibit SARS-CoV-2 in healthcare workers. They offer a non-pharmaceutical public health intervention consisting of mouthwash and nosewash with AgNPs solution to reduce the morbidity of healthcare workers exposed to the SARS-CoV-2 virus.
Researchers have shown clinical evidence confirming the prevention of SARS-CoV-2 infection in healthcare workers who performed mouthwash and nose rinse solution with AgNPs.
To our knowledge, this study is the first experimental in vitro and in vivo trial where AgNPs in the form of mouthwash and nasal rinse solution are applied for the prevention of the contagion of SARS-CoV-2 ”, state the researchers .
The study, published on the preprint medRxiv* server, tested an ARGOVIT® AgNPs mouthwash that contains AgNPs and evaluated for the prevention of SARS-CoV-2 infection in healthcare workers.
This is a registered oral and nasal hygiene product made in Russia. It contains metallic silver, polyvinylpyrrolidone, hydrolyzed collagen and distilled water. Hydrolyzed collagen stabilizes AgNPs and reduces cytotoxicity. AgNPs have been shown to have strong antimicrobial effects, including antiviral.
First, they demonstrated the antiviral activity of AgNPs in Vero E6 cell cultures. The researchers observed a dose-dependent inhibitory effect of AgNPs on the infectivity of SARS-CoV-2.
Second, the researchers designed a two-group randomized controlled study (experimental vs control) to assess the effectiveness of mouthwash and nasal rinse with AgNPs solution in preventing SARS-CoV-2 infection in staff. health center at Tijuana General Hospital in Mexico. These people (n = 231) work in high-risk areas in direct contact with patients infected and diagnosed with COVID-19 and / or atypical pneumonia.
This study was carried out for 9 weeks when the pandemic was declared in Mexico (April 7 to June 9, 2020). Researchers confirmed the diagnosis of COVID-19 among the participants by monitoring symptoms, performing RT-PCR, randomly selecting CT scans and clinical evaluation.
Using logistic regression, the strong relationship between the fact of mouth and nosewashes in healthcare workers and the attenuation of SARS-CoV-2 contagion with an efficiency of 84.8% is proven. “
Significantly, the study also showed no harmful side effects in participants who used AgNPs as a mouthwash and nasal rinse for 9 weeks. The researchers observed that the incidence of SARS-CoV-2 infection was significantly reduced in the “experimental” group (two out of 114 participants were COVID-19 positive, 1.8%) compared to the “control group. (Thirty-three of 117 participants were COVID-19 positive, 28.2%). This calculated at an efficiency of 84.8%, suggesting that mouthwash could be an effective use of AgNPs in preventing SARS-CoV-2 infection.
The researchers also recommended the app to prevent SARS-CoV-2 infection in high-risk areas such as dental procedures. Since the oropharynx and nasopharynx are the initial entry sites for SARS-CoV-2 and replicate to produce a viral load of 1.2 × 108 infectious copies / per mL, this is ‘a high risk of exposure for the dentist.
The evidence presented in this study suggests that the application of mouthwashes and nose rinses can significantly reduce the viral load in these areas, to reduce transmission, in addition to the use of personal protective equipment by staff. health, ”the researchers said.
This study presents a new non-pharmaceutical intervention using nanoparticles in a clinical setting to reduce the spread and / or pathogenicity of SARS-CoV-2 associated with COVID-19.
Prove its inhibitory effect on the infectivity of SARS-CoV-2 in vitro it is deduced that the use of AgNPs as mouthwash and nose rinse will be very useful as a prophylactic for the prevention of SARS-CoV-2, not only for health personnel, but also as additional protection for the general population, write the researchers.
medRxiv publishes preliminary scientific reports which are not peer reviewed and, therefore, should not be considered conclusive, guide clinical practice / health-related behaviors, or treated as established information.
- Horacio Almanza-Reyes, Sandra Moreno, Ismael Plascencia-Lopez, Martha Alvarado-Vera, Leslie Patron-Romero, Belen Borrego, Alberto Reyes-Escamilla, Daniel Valencia-Manzo, Alejandro Brun, Alexey Pestryakov, Nina Bogdanchikova. Assessment of silver nanoparticles for the prevention of SARS-CoV-2 infection in health workers: in vitro and in vivo. medRxiv 2021.05.20.21256197; do I: https://doi.org/10.1101/2021.05.20.21256197, https://www.medrxiv.org/content/10.1101/2021.05.20.21256197v1