Virucidal effect of mouthwash on acyclovir-resistant herpes simplex virus.

Objectives: The symptoms of herpes simplex viruses type 1 (HSV-1) infections might be severe and persistent in immunocompromised patients in whom they reactivate at a high frequency. The development of Acyclovir (ACV) resistant strains due to long-term treatment with antiviral agents in those patients is not uncommon. The aim of the present study was to assess the virucidal effect of commercially available mouthwashes against ACV-resistant HSV-1 strains.

Materials And Methods: Two acyclovir-resistant HSV-1 strains were exposed for 30 s to essential oil-based (Listerine Fresh Burst® and Listerine Zero®), chlorhexidine gluconate 0.2% (Hexidyl®) and povidone-iodine 7.5% (Betadine Gargle®) mouthwashes. Loss of virus infectivity was determined by means of plaque reduction assays in a cell culture system.

Results: All 4 of the tested solutions significantly reduced virus infectivity, with the essential oil-based and povidone-iodine mouthwashes being slightly more efficacious, compared to chlorhexidine.

Conclusion: The findings of this analysis revealed that the tested oral rinses demonstrated in-vitro antiviral activity against ACV-resistant HSV. Comparative clinical trials are required to establish the clinical effectiveness of daily use of oral rinses in reducing the appearance of oral HSV lesions in immunocompromised patients.