key: cord-1017920-pwn9wgi5 authors: Maurya, Raj Kumar; Singh, Harpreet; Kapoor, Pranav; Sharma, Poonam; Srivastava, Dhirendra title: Povidone-iodine preprocedural rinse—An evidence-based, second-line defense against severe acute respiratory coronavirus virus 2 (SARS-CoV-2) in dental healthcare date: 2021-03-12 journal: Infection control and hospital epidemiology DOI: 10.1017/ice.2021.90 sha: 2cd714c96c5e98d849f8e9eeacf94c4457521b6b doc_id: 1017920 cord_uid: pwn9wgi5 The ongoing COVID-19 pandemic has posed unique challenges to dentistry as a profession and has prompted dental healthcare professionals worldwide to risk manage the delivery of dental care by taking cognizance of the necessity for enhanced safety standards, including enhanced 'personal protective equipment' and 'infection prevention and control' measures. Even so, in light of the perceived vulnerability to the coronavirus infection in dental settings or becoming potential carriers in dental settings, implications for resumption of routine dental care are enormous and cannot be ignored. While reconciling the fact that post-pandemic resurgences can occur in future, safeguarding the oral health care workforce and patients becomes even more pertinent considering the perceived vulnerability to the SARS-CoV-2 infection in dental healthcare. With growing body of direct evidence consistently supporting the effectiveness of Povidone-Iodine against SARS-CoV-2, it would be reasonable to prioritize the use of PVP-I as an effective and adjunctive procedural risk mitigation measure in dental healthcare occupation in the contemporary pandemic crisis and through unforeseen similar pandemic threats. To the Editor-Ever since it began, coronavirus disease 2019 (COVID-19) pandemic has brought disruptions to almost all aspects of society, with far-reaching adverse impacts on clinical and economic fronts. Even amid effective vaccine rollout, which has rekindled the hope of ending this unprecedented global disaster, the COVID-19 pandemic continues unabated, with reports of a highly transmissible, mutant, severe acute respiratory coronavirus virus 2 (SARS-CoV-2) VOC 202012/01 strain and another SARS-CoV-2 20H/501Y.V2 variant. These strains could drive even larger waves of disease. 1 Due to high viral loads and the consequent transmission potential of asymptomatic and minimally symptomatic patients, 2 reducing the viral load in the oropharynx with adequate oral prophylactic measures is imperative to contain and prevent the spread of SARS-CoV-2 in public and dental healthcare settings. Considering the high-risk nature of the dental healthcare occupation due to the propensity for close-contact transmission through infective saliva, droplet splatter, and blood-mixed aerosols, procedural mitigation strategies involving prophylactic use of preprocedural mouth rinses (PPMRs) has been recommended to attenuate nosocomial transmission of SARS-CoV-2. 3 Different oral antiseptic agents have been employed as a second layer of defence against microbial load in dental aerosols: povidone-iodine (PVP-I), chlorhexidine gluconate (CHX), hydrogen peroxide, cetylpyridinium chloride (CPC), and essential oils. 4 A comparative in vitro study evaluating virucidal efficacy of different oral rinses demonstrated that mouth formulations containing 1% PVP-I, combination of dequalinium chloride and benzalkonium chloride, and a combination of ethanol and essential oils can significantly reduce SARS-CoV-2 viral infectivity within short exposure times of 30 seconds. 5 However, CHX-based mouth rinse exhibited weak virucidal efficacy. A recent systematic review found no scientific evidence supporting the virucidal activity of hydrogen peroxide mouthwash. 6 With the growing evidence amid the COVID-19 pandemic, evidence-based recommendations in favor of PVP-I as PMR have been increasing. PVP-I or iodopovidone has been ubiquitously used as an antiseptic in healthcare settings for decades. Comprising iodine and the water-soluble polymer polyvinylpyrrolidone, PVP-I is considered favorable for its slow and gradual iodine release, minimizing toxicity, and for the resultant viral inactivation arising from its oxidative effect and lipid shell-membrane destruction. 7 Regarding the virucidal activity of PVP-I against SARS-CoV-2, Bidra et al 8 12 Rinsing with 0.075% CPC and 0.5% PVP-I for 30 seconds decreased the salivary SARS-CoV-2 levels within 5 minutes of use, and the subsequent effects were sustained at 6-hour time points. No cytotoxic effects of 1% PVP-I mouthwash have been reported when used at a concentration of 0.63 mg/mL (ie, 1:16 or lower dilution of the product). 9 Moreover, in addition to a well-established safety profile, PVP-I also exhibits good tolerability at concentrations as high as 2.5% for up to 5 months, with the absence of tooth or tongue discoloration or taste disturbances. 13 Unlike alcohol-based mouth rinse, it can also be used in conjunction with electrocautery, which also make it a suitable choice for use in maxillofacial surgery. Few contraindications for the use of PVP-I solutions include type 1 anaphylactic allergy to iodine (rarely encountered), active thyroid disease, pregnancy, and radioactive iodine therapy. Hence, proper medical and drug history should be reviewed before their use. In view of the fluid situation posed by the ongoing pandemic, Kirk-Bailey et al 14 recommend the use of 9 mL 0.5% PVP-I as a mouthwash and 0.28-0.3 mL 0.5% PVP-I as a nasal spray solution in each nostril, both for the patient before examination and/or treatment, and for the clinical staff prior to patient contact (repeated every 2-3 hours, up to 4 times a day, if multiple patients are seen). Due to the chemical instability of PVP-I with respect to disproportionation into constituent equilibrium species, freshly prepared dilutions should be used, and they should be preserved in the refrigerator for subsequent patients through the day. 8 While reconciling the fact that postpandemic resurgences may occur as late as 2024, 15 safeguarding the oral healthcare workforce and patients becomes even more pertinent considering the perceived vulnerability to the SARS-CoV-2 infection in dental settings. With a growing body of direct evidence consistently supporting the effectiveness of PVP-I against SARS-CoV-2, it would be reasonable to prioritize the use of PVP-I as an effective and adjunctive procedural risk mitigation measure in dental healthcare in the contemporary pandemic crisis and through unforeseen similar pandemic threats. Estimated transmissibility and severity of novel SARS-CoV-2 variant of concern 202012/01 in England SARS-CoV-2 viral load in upper respiratory specimens of infected patients Transmission routes of 2019-nCoV and controls in dental practice Aerosols and splatter in dentistry: a brief review of the literature and infection control implications Virucidal efficacy of different oral rinses against severe acute respiratory syndrome coronavirus 2 Do hydrogen peroxide mouthwashes have a virucidal effect? A systematic review Prevention of respiratory infections by povidone-iodine gargle Rapid in vitro inactivation of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) using povidone-iodine oral antiseptic rinse In vitro virucidal activity of povidone iodine gargle and mouthwash against SARSCoV-2: implications for dental practice Povidone-iodine demonstrates rapid in vitro virucidal activity against SARS-CoV-2, the virus causing COVID-19 disease Is povidone iodine mouthwash effective against SARS-CoV-2? First in vivo tests Efficacy of commercial mouthrinses on SARS-CoV-2 viral load in saliva: randomized control trial in Singapore Povidone-iodine use in sinonasal and oral cavities: a review of safety in the COVID-19 era The use of povidone iodine nasal spray and mouthwash during the current COVID-19 pandemic may reduce cross infection and protect healthcare workers Projecting the transmission dynamics of SARS-CoV-2 through the postpandemic period Acknowledgments.Financial support. No financial support was provided relevant to this article. All authors report no conflicts of interest relevant to this article.