As an evolutionary biologist, I am more worried about our current cleaning habits than I am about COVID-19. Good, sanitary practices are a good thing, but what worries me is how we are dealing with mass sterilization to combat the virus.
COVID-19 is a virus. Hand washing is preferable to using hand sanitizer because it physically knocks viruses off your skin. It turns out that plain old soap is really effective against viruses. But many soaps add extra antimicrobial or antibiotic chemicals into their mixture, ostensibly boosting their efficacy. Here’s the problem: those antimicrobial additives only work on bacteria and fungi. They do nothing against viruses.
At least those antimicrobial soaps are killing off other germs, right? Yes, but that isn’t necessarily good. We harbor a huge variety of beneficial bacteria on and in our bodies and this microbiome is remarkably important to our health. More importantly, antibacterials are not 100% effective at killing all microbes.
Microbes can (and do) evolve immunity to antibiotics. In a war against disease-causing microbes, antibiotic agents are our best weapon. The more we apply antimicrobial agents, the more defenses microbes develop against them. The bacteria causing both staph infections (MRSA) and tuberculosis (TB) are already known to have multi-drug resistant strains, meaning they are immune to more than one class of antibiotic. These bacteria are evolving faster than we can develop new types of antimicrobials to fight them off. And as we throw antibiotics on surfaces to combat COVID-19, we could be aiding the development of something far scarier: antibiotic-resistant microbes.
So while we deal with the current pandemic, continue to wash your hands, but please be responsible and make sure your cleaning products and soap do not contain antibiotics or antimicrobial additives. Just stick to plain soap and water.