Sir, hand washing with soap or antimicrobial gels to reduce the transmission of infectious diseases, including COVID-19, is based on sound biological principles. Thus, soaps, detergents and antiseptics can destroy or remove a range of infectious microbes from the hands, thereby reducing the risk of indirect self or person to person infection. COVID-19 is a respiratory infection, where transmission between individuals is primarily by droplet spread of the coronavirus by coughing or sneezing. From my own knowledge and listening to experts, a major source of droplets are derived from saliva. I am therefore somewhat surprised that our profession has not been promoting oral hygiene, through toothbrushing with toothpaste, in the preventive approach to COVID-19. The majority, if not all toothpastes, contain detergents, which confer significant antimicrobial properties to the product, indeed the same detergents are present in many hand washing formulations, recommended against coronavirus.

The recommendation to tooth brush with toothpaste for two minutes twice a day, I believe, should be reinforced by the dental profession, the media and the government and its advisors. Although, we may assume such oral hygiene practices are already the norm, this is certainly not the case, particularly for those individuals who coincidentally are most at risk of contracting COVID-19. This includes the elderly, particularly in nursing and retirement homes, where hygiene practices often depend on carers. Finally, I would address the idea of using antimicrobial mouthrinses, particularly chlorhexidine products. Unfortunately, the evidence base for their use in preventing or reducing transmission of coronavirus infection is not in place. Indeed, although some antiseptic rinses, including chlorhexidine, have antiviral action, the lipid outer layer of coronavirus would probably protect against such agents.