The short-term effect of different chlorhexidine forms versus povidone iodine mouth rinse in minimizing the oral SARS-CoV-2 viral load: An open label randomized controlled clinical trial study

Abstract

Several investigations evaluated the possibility of different types of mouth wash rinse in minimizing the SARS-CoV-2 load. However, results still controversial. The study aim is to assess the short-term efficiency of several over-the-counter mouth rinses and lozenges in minimizing the salivary viral load for SARS-CoV-2 in patients with confirmed COVID-19 in comparison to saline. This is a randomized controlled clinical trial with 4 arms. The recruited cases were randomized using a simple randomization technique and were assigned to chlorhexidine digluconate mouth rinse (CHX mouth rinse), 2 mg of chlorhexidine digluconate lozenges (CHX lozenges), povidone iodine mouth rinse (PVP-I mouth rinse) or saline as a control group. Saliva were collected from all study subjects by passive drool technique at two time points. First, prior to intervention with mouth rinse or the lozenges, the baseline saliva sample was collected. Second saliva samples were collected immediately after the mouth rinse. Real time PCR was conducted and the value threshold cycle (Ct) for each sample was recorded.Majority of the participants had an education level of high school or less (60%), were married (68.3), males (58.3%), and nonsmokers (58.5%). No statistically significant differences between groups at the two times test (P > .05). However, a significant decrease of salivary viral load in all four groups combined (P-value for E genes = .027, and for S genes = .006), and in PVP-I mouth rinse specifically (P = .003 and P = .045, respectively). Povidone iodine mouth rinse showed a potential influence on the reduction of the viral load on a short-term basis. However, longer-term studies of the effect of these products should be conducted. Abbreviations: CHX mouth rinse = digluconate mouth rinse, CHX lozenges = chlorhexidine digluconate lozenges, PVP-I mouth rinse = povidone iodine mouth rinse, Ct = threshold cycle, SARS-CoV-2 = Severe Acute Respiratory Syndrome Coronavirus 2, KFGH = King Fahad General Hospital, RT-PCR = Real-time polymerase chain reaction.

The efficacy of mouthwashes in reducing SARS-CoV-2 viral loads in human saliva: A systematic review

“…1 ). Of these, 51 articles were selected for a full-text review and 11 met the inclusion criteria: Two observational and nine experimental studies [ [9] , [10] , [11] , [12] , [13] , [14] , [15] , [16] , [17] , [18] , [19] ].

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“…The following mouthwashes were prescribed: CHX in eight studies with the dosage of 0.12, and 0.2% [ [10] , [11] , [12] , [13] , [14] , [15] , 17 , 18 ], PI with the dosage of 0.4, 0.5, 0.6, 1, and 2% in eight studies [ 11 , 12 , [14] , [15] , [16] , [17] , [18] , [19] ], the dose of 0.07 % of CPC in four studies [ 10 , 11 , 14 , 18 ], HP with the dosage of 1, and 1.5 % in four studies [ [10] , [11] , [12] , 18 ], CDCM in one study [ 9 ], and 0.02% HCIO in one study [ 19 ]. Mouth rinses in the intervention groups were compared with distilled water as the control groups for nine of the studies [ [10] , [11] , [12] , [14] , [15] , [16] , [17] , [18] , [19] ]. In the study of Carrouel et al, the control group used a placebo as mouthwash [ 9 ].…”

“…The outcome was measured through RT-PCR: % reduction in viral load was the target. Studies evaluated salivary viral load clearance with CT value changes [ 9 , 10 , 12 , 14 , 15 , [17] , [18] , [19] ] and/or RT-PCR [ 14 ], quantitative RT-PCR [ [9] , [10] , [11] , [12] , 18 ], qualitative RT-PCR [ 16 ], and real-time RT-PCR [ 13 , 15 , 17 , 19 ].…”

“…Eight studies evaluated the efficacy of CHX [ [10] , [11] , [12] , [13] , [14] , [15] , 17 , 18 ]. Four examined 0.12% CHX mouth rinses and measured viral load reduction at 5 and 60 minutes.…”

“…None of the healthcare workers developed COVID-19 infection during the study time, whilst nearly 50% of all healthcare workers in their respective hospitals developed infection [ 13 ]. Also, in the study conducted by Natto et al, both CHX mouthrinse and lozenges were administrated and significantly reduced the viral load [ 17 ]. However, three studies indicated no significant difference using the CHX mouth rinses [ 11 , 14 , 18 ].…”