In vitroassessment of the virucidal activity of four mouthwashes containing Cetylpyridinium Chloride, ethanol, zinc and a mix of enzyme and proteins against a human coronavirus

Abstract

Background: saliva is established to contain high counts SARS-CoV-2 virus and contact with saliva droplets, contaminated surfaces or airborne particles are sources of viral transmission. The generation of infective aerosols during clinical procedures is of particular concern. Therefore, a fuller understanding of the potential of mouthwash to reduce viral counts and modulate the risk of transmission in medical professional and public context is an important research topic. Method: we determined the virucidal activity of four anti-bacterial mouthwashes against a surrogate for SARS-CoV-2, Human CoV-SARS 229E, using a standard ASTM suspension test, with dilution and contact times applicable to recommended mouthwash use. Results: the mouthwash formulated with 0.07% Cetylpyridinium Chloride exhibited virucidal effects providing a ≥3.0 log reduction HCoV-229E viral count. Mouthwashes containing 15.7% ethanol, 0.2% zinc sulphate heptahydrate and a mix of enzymes and proteins did not demonstrate substantive virucidal activity in this test. Conclusion: mouthwash containing 0.07% Cetylpyridinium Chloride warrants further laboratory and clinical assessment to determine their potential benefit in reducing the risk of SARS-CoV-2.

Brief Report: The Virucidal Efficacy of Oral Rinse Components Against SARS-CoV-2 In Vitro

“…Our data, using an assay that enabled us to detect up to 5-log10 reduction in SARS-CoV2 activity, further support the accumulating evidence for high virucidal activity by widely-available mouthwashes in vitro , against SARS-CoV2 and the related HCoV-229E coronavirus strain [3–5]. Here, three products which contained either (i) 0.07-0.1 % CPC (Dentyl Dual Action, Dentyl Fresh Protect) or (ii) 23 % ethanol with LAE (Listerine Advanced) provided the greatest level of inactivation, surpassing the level required for EN14476.…”

“…Second, infectivity of the closely related HCoV-229E coronavirus was reduced by 3-4-log10 using several agents including CPC, ethanol/essential oils and PVP-I [4]. Inactivation of HCoV-229E by >3-log10 by CPC at 0.07% was also shown in a recent preprint [5]. So far, only one of the products tested (Listerine Antiseptic, combining 26.9% alcohol with essential oils) achieved the 4-log10 kill required to pass EN14476 as a virucidal [4].…”

Virucidal activity of oral care products against SARS-CoV-2 in vitro

“…The Center for Disease Control (CDC) and American Dental Hygienists’ Association (ADHA) have recommended use of CPC- or CHX-containing mouthwash before the dental procedure against COVID-19 [ 11 , 12 ]. However, only a few reports have examined an inactivating effect of CHX on SARS-CoV-2 [ 7 , 13 ] and some have suggested effects of CPC on other viruses [ 3 , 14 , 15 , 16 , 17 ], but with no certified data on direct inactivation effects of CPC on SARS-CoV-2 [ 18 ]. On the other hands, in previous studies, virucidal activities were tested against some Coronaviruses [ 19 , 20 ].…”

Los enjuagatorios bucales en tiempos de Covid-19

“…2. A la fecha, los estudios in vitro demuestran una baja efectividad de los enjuagues bucales que contienen digluconato de clorhexidona (CHX), etanol o aceites esenciales en las concentraciones habituales de uso (8,9,10,11) .…”

“…El cloruro de cetilpiridinio (CCP), es un compuesto de amonio cuaternario presente en varios enjuagues bucales y aerosoles para el aliento. Posee una probada actividad antiséptica y antimicrobiana, y se ha demostrado in vitro, que reduce mil veces la infectividad del SARS-CoV-2 al inhibir la fusión del virus con las células diana y además tendría un efecto mantenido en la reducción del nivel salival de SARS-CoV-2 en pacientes con COVID-19 (8,9,10,12,13) .…”