Virucidal Efficacy of Different Oral Rinses Against Severe Acute Respiratory Syndrome Coronavirus 2
Meister et al.
, Virucidal Efficacy of Different Oral Rinses Against Severe Acute Respiratory Syndrome Coronavirus 2
, The Journal of Infectious Diseases, doi:10.1093/infdis/jiaa471 (In Vitro)
analysis of 8 oral rinses, showing reduced viral infectivity up to 3 orders of magnitude with povidone-iodine, ethanol + essential oils, and dequalinium chloride + benzalkonium chloride, and log reduction factors ranging from 0.3 to 1.78 for the other 5.8 In Vitro studies
support the efficacy of povidone-iodine [Anderson, Bidra, Frank, Hassandarvish, Meister, Pelletier, Tucker, Xu]
Meister et al., 29 Jul 2020, Germany, peer-reviewed, 12 authors.
In Vitro studies are an important part of preclinical research, however results may be very different in vivo.
Abstract: The Journal of Infectious Diseases
Virucidal Efficacy of Different
Oral Rinses Against Severe Acute
Respiratory Syndrome Coronavirus 2
Toni Luise Meister,1 Yannick Brüggemann,1 Daniel Todt,1,2 Carina Conzelmann,3
Janis A. Müller,3 Rüdiger Groß,3 Jan Münch,3 Adalbert Krawczyk,4,5
Jörg Steinmann,6,7 Jochen Steinmann,8 Stephanie Pfaender,1,a and Eike Steinmann1,a
The ongoing severe acute respiratory syndrome coronavirus 2
(SARS-CoV-2) pandemic creates a significant threat to global
health. Recent studies suggested the significance of throat and
salivary glands as major sites of virus replication and transmission during early coronavirus disease 2019, thus advocating
application of oral antiseptics. However, the antiviral efficacy
of oral rinsing solutions against SARS-CoV-2 has not been
examined. Here, we evaluated the virucidal activity of different
available oral rinses against SARS-CoV-2 under conditions
mimicking nasopharyngeal secretions. Several formulations
with significant SARS-CoV-2 inactivating properties in vitro
support the idea that oral rinsing might reduce the viral load of
saliva and could thus lower the transmission of SARS-CoV-2.
Keywords. SARS-CoV-2; oral rinses; inactivation; suspension test; transmission.
The current severe acute respiratory syndrome coronavirus
2 (SARS-CoV-2) pandemic has created a significant threat to
global health. Since effective treatments and vaccines are currently not available, diligent attention on transmission-based
precautions is essential to limit viral spread. According to current
evidence, SARS-CoV-2 is mainly transmitted through respiratory droplets exhaled from infected individuals . Importantly,
viral loads are high in the nasal cavity, nasopharynx, and oropharynx and viral shedding can be detected before, during, and
after the acute clinical phase of illness . Aerosols produced
Received 18 June 2020; editorial decision 21 July 2020; accepted 24 July 2020; published
online July 29, 2020.
S.P. and E.S. are equally contributing last authors.
Correspondence: Eike Steinmann, PhD, Department of Molecular and Medical Virology, RuhrUniversity Bochum, Universitaetsstr 150, 44801 Bochum, Germany (email@example.com).
The Journal of Infectious Diseases® 2020;222:1289–92
© The Author(s) 2020. Published by Oxford University Press for the Infectious Diseases Society
of America. All rights reserved. For permissions, e-mail: firstname.lastname@example.org.
Virus Strains and Propagation
To isolate SARS-CoV-2 at the University Ulm Medical Center
(Ulm, Germany), 50 000 Vero E6 cells were seeded in 24-well
plates in 500 µL medium incubated overnight at 37°C. The next
day, medium was replaced by 400 µL of 2.5 µg/mL amphotericin
B–containing medium. Then, 100 µL of throat swabs that tested
positive for SARS-CoV-2 by reverse-transcription quantitative
polymerase chain reaction was titrated 5-fold on the cells and
incubated for 3–5 days. Upon visible cytopathic effect, supernatant was taken and virus expanded by inoculation of Vero
E6 cells in 75 cm2 flasks and propagated as described above.
Thereby, the viral isolates BetaCoV/Germany/Ulm/01/2020
(strain 2) and BetaCoV/Germany/Ulm/02/2020 (strain 3) were
obtained. In Essen, Germany, SARS-CoV-2 was isolated from
a nasopharyngeal swab of a patient suffering from coronavirus
disease 2019 (COVID-19) and named UKEssen strain (strain
1). The swab was taken using a Virocult vial (Sigma, Germany).
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