Why Mouthwash Is Not a Covid-19 Solution
A new study has a lot of caveats
A new study is getting plenty of buzz for suggesting that mouthwash may swish away coronaviruses and possibly act as an additional layer against virus transmission. If only it were that simple.
The researchers of the study, published in the Journal of Medical Virology, grew a type of coronavirus called 229E in human liver cells in a lab and observed the effect that various mouthwashes and a baby shampoo had on the virus. They found that about 90% to 99% of the viruses could no longer infect cells afterward.
There are many reasons to look at this new study skeptically. First, the researchers did not actually study SARS-CoV-2, the virus that causes Covid-19. The coronavirus they studied is significantly less severe.
Second, the researchers studied how mouthwash inactivated viruses in a lab setting and not in the mouths of humans. So the study suggests very little about how a mouthwash would impact the virus that causes Covid-19 in real-world settings (your bathroom).
Third, a mouthwash strategy for Covid-19 prevention doesn’t take into account how SARS-CoV-2 infects people. Gargling a lot of mouthwash is unlikely to have an effect on the virus that’s already in the body. The virus can get into people’s throats, lungs, and blood vessels and replicate.
Of course, I am not going to recommend that people stop using mouthwash. Just don’t start using it as a way to protect against Covid-19. What works for that is masking, distancing, and washing your hands.