It’s hard to keep up with changes in COVID-19 safety precautions since the pandemic began, but any greatest-hits package must include sanitizing hard surfaces and even food packaging.
Remember wiping down your groceries before transferring them from the shopping cart to your car? And frequent hand-washing?
Studies at the time showed people could get infected by touching contaminated surfaces or objects, then touching their nose, mouth or eyes. That threat, despite vanishing from public awareness, actually has increased with each COVID-19 variant, according to new Japanese research. Omicron survived a stunning 193.5 hours on plastic and 21.1 hours on human skin, far longer than the original variant, in new research at the National Institute of Infectious Diseases in Tokyo.
Researchers obtained samples of each variant — the original, Alpha, Beta, Gamma, Delta and Omicron — and tested survivability on both plastic and human skin samples.
Here are the results on plastic, as posted in the preprint study on bioRxiv:
- Original: 56 hours.
- Gamma: 59.3 hours.
- Delta: 114 hours.
- Beta: 156.6 hours.
- Alpha: 191.3 hours.
- Omicron: 193.5 hours.
Here are the results on human skin:
- Original: 8.6 hours.
- Gamma: 11 hours.
- Delta: 16.8 hours.
- Beta: 19.1 hours.
- Alpha: 19.6 hours.
- Omicron: 21.1 hours.
“This study showed that the Omicron variant also has the highest environmental stability among (variants of concern),” the researchers wrote, “which suggests that this high stability might also be one of the factors that have allowed the Omicron variant to replace the Delta variant and spread rapidly.”
Remember, these laboratory results might not translate into everyday life, given changes in real-world temperature and humidity that could shorten the viruses’ survival period. In further tests using test tubes, the researchers found Omicron somewhat more resistant than the original Wuhan strain to sanitizing with ethanal. On human skin, however, each strain was effectively inactivated with a 15-second exposure to a 35 percent alcohol solution.
Hygiene still counts in the COVID era.
“The problem with COVID,” says Dr. Ulysses Wu, Hartford HealthCare’s System Director of Infection Disease and Chief Epidemiologist, “is that even with personal choice, there is a societal consequence. We do have to remember that. It’s not the same as just not wearing your seatbelts or not washing your hands before you eat.”