Saliva samples from COVID-19-positive individuals have been shown to have significant viral loads, increasing the risk of infection for healthcare workers engaged in aerosol-generating procedures. Pre-procedural rinses have been studied for their efficacy in decreasing the spread of infection by lowering the colony-forming unit (CFU) count in aerosols and the microbial load in the patient′s saliva before medical or dental operations. Research has shown that povidone-iodine (PVP-I) mouthwash is one of the most effective mouthwash solutions. PVP-I as a pre-procedure mouthwash has been the subject of a number of published in-vitro investigations and, more recently, randomized controlled trials (RCTs).

The objective of the review was to confirm whether there is evidence in the literature describing a reduction in salivary load of SARS-CoV-2 when povidone-iodine (PVP-I) is used as a pre-intervention mouthwash. The authors extensively searched the MEDLINE, Embase, SCOPUS, and Cochrane library databases. Eventually, four articles were included that met the established criteria. 

Results showed that PVP-I, at concentrations between 0.5% and 1%, significantly inhibited the replication of SARS-CoV-2 in human saliva. However, one study found no statistically significant differences in salivary load at a concentration of 2%. Patients with confirmed, suspected, or asymptomatic COVID-19 infection may benefit from a 30- or 60-second pre-procedural washing with 0.50/1% PVP-I in healthcare settings doing aerosol-generating procedures.

According to this review, PVP-I is effective against SARS-CoV-2 in saliva and could be implemented as a rinse before interventions to decrease the risk of cross-infection in healthcare settings.

Source: International journal of environmental research and public health, 19(5), 2877.