Rapid In‐Vitro Inactivation of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS‐CoV‐2) Using Povidone‐Iodine Oral Antiseptic Rinse

Abstract

Purpose: To investigate the optimal contact time and concentration for viricidal activity of oral preparation of povidone-iodine (PVP-I) against SARS-CoV-2 ('corona virus') to mitigate the risk and transmission of the virus in the dental practice. Materials and Methods:The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) USA-WA1/2020 strain, virus stock was tested against oral antiseptic solutions consisting of aqueous povidone-iodine (PVP-I) as the sole active ingredient. The PVP-I was tested at diluted concentrations of 0.5%, 1%, and 1.5%. Test media without any virus was added to 2 tubes of the compounds to serve as toxicity and neutralization controls. Ethanol (70%) was tested in parallel as a positive control, and water only as a negative control. The test solutions and virus were incubated at room temperature (22 ± 2 °C) for time periods of 15 and 30 seconds. The solution was then neutralized by a 1/10 dilution in minimum essential medium (MEM) 2% fetal bovine serum (FBS), 50 µg/mL gentamicin. Surviving virus from each sample was quantified by standard end-point dilution assay and the log reduction value (LRV) of each compound compared to the negative (water) control was calculated. Results: PVP-I oral antiseptics at all tested concentrations of 0.5%, 1%, and 1.5%, completely inactivated SARS-CoV-2 within 15 seconds of contact. The 70% ethanol control group was unable to completely inactivate SARS-CoV-2 after 15 seconds of contact, but was able to inactivate the virus at 30 seconds of contact. Conclusions: PVP-I oral antiseptic preparations rapidly inactivated SARS-CoV-2 virus in vitro. The viricidal activity was present at the lowest concentration of 0.5 % PVP-I and at the lowest contact time of 15 seconds. This important finding can justify the use of preprocedural oral rinsing with PVP-I (for patients and health care providers) may be useful as an adjunct to personal protective equipment, for dental and surgical specialties during the COVID-19 pandemic.

Comparison of In Vitro Inactivation of SARS CoV‐2 with Hydrogen Peroxide and Povidone‐Iodine Oral Antiseptic Rinses

“…[2][3][4] Therefore, any dental procedure, especially prosthodontic procedures, which can aerosolize contaminated saliva (using handpieces, air-water syringes, and ultrasonic instrumentation), has the potential to significantly increase airborne transmission of the virus. [5][6][7] All of this places dental professionals at a significantly higher risk for infection, and be a source for further transmission of infection. This behooves dental professionals to consider additional and augmented protocols for infection control in the dental office.…”

“…This behooves dental professionals to consider additional and augmented protocols for infection control in the dental office. 6,7 The nasal and oral cavities are considered a major portal of entry for SARS-CoV-2, and are directly associated with the evolutionary process of COVID-19. They are involved in inhalation of virus containing droplet particles and aerosols in the ambient regions, as well as in expectorations of virus containing droplets.…”

“…10,11 An additional component of protection that has recently begun to receive increased attention is the use of preprocedural oral rinses. 2,3,7,12 Due to the knowledge that the oropharyngeal region is a major site of viral replication during the early asymptomatic stages of COVID-19, it has been suggested that oral antiseptic rinses that target the lipid envelope of SARS-CoV-2, has the potential to reduce viral load in the oropharynx. 12 There is increasing recognition that oral antiseptic rinses with significant viricidal activity may have a role as potential therapeutic agents to inactivate infective particles generated in the oropharyngeal region.…”

“…12 There is increasing recognition that oral antiseptic rinses with significant viricidal activity may have a role as potential therapeutic agents to inactivate infective particles generated in the oropharyngeal region. 7,12,13 Recent articles have discussed the importance of preprocedural oral antiseptic rinses for use on patients as well as dental and medical professionals, in order to reduce the risk of transmission associated with viral shedding from asymptomatic individuals. 6,7,14 A variety of oral antiseptic rinses have been suggested in recent literature for preprocedural use to reduce viral transmission.…”

“…7,12,13 Recent articles have discussed the importance of preprocedural oral antiseptic rinses for use on patients as well as dental and medical professionals, in order to reduce the risk of transmission associated with viral shedding from asymptomatic individuals. 6,7,14 A variety of oral antiseptic rinses have been suggested in recent literature for preprocedural use to reduce viral transmission. 12 Oral rinses ranging from chlorhexidine gluconate, ethanol, essential oils, povidone-iodine (PVP-I), hydrogen peroxide (H 2 O 2 ) chlorinated water, hypertonic saline, bioflavonoids, cyclodextrins, cetylpyridinium chloride have been recommended.…”