Coronavirus traces lingered in vacated cruise cabins for weeks
Mar 23, 2020
Bloomberg – Traces of new coronavirus were found on surfaces in cruise-ship cabins for as many as 17 days after passengers left, researchers said, though it wasn’t possible to determine whether they caused any infections.
Researchers looked at the rooms of infected passengers aboard the Diamond Princess, both those who showed symptoms and those who didn’t, according to a study Monday in the Centers for Disease Control and Prevention’s Morbidity and Mortality Weekly Report.
The ship, operated by Carnival Corp.’s Princess Cruises, had more than 700 coronavirus cases. It was quarantined for a time off of Yokohama, Japan, and was the largest outbreak outside of mainland China at one point.
A previous analysis found that the virus remained viable on plastic and stainless steel for up to three days, although levels fell dramatically over time.
It was less stable on copper, where no viable virus was found after 4 hours, and cardboard, which was clean after 24 hours, according to the report in the New England Journal of Medicine … Read more.
How Long Does Coronavirus Live On Surfaces?
Carolyn Machamer, a cell biologist who specializes in coronaviruses, discusses the latest research on the virus that causes COVID-19
March 20, 2020
Johns Hopkins University – According to a recent study published in the New England Journal of Medicine, SARS-CoV-2, the virus that causes COVID-19, can live in the air and on surfaces between several hours and several days.
The study found that the virus is viable for up to 72 hours on plastics, 48 hours on stainless steel, 24 hours on cardboard, and 4 hours on copper.
It is also detectable in the air for three hours.
Carolyn Machamer, a professor of cell biology whose lab at the Johns Hopkins School of Medicine has studied the basic biology of coronaviruses for years, joined Johns Hopkins MPH/MBA candidate Samuel Volkin for a brief discussion of these findings and what they mean for efforts to protect against spread of the virus. The conversation has been edited for length and clarity.
Volkin: According to this report, it sounds like the COVID-19 virus is potentially living on surfaces for days. How worried should we be about our risk of becoming infected simply by touching something an infected person was in contact with days ago?
Machamer: What’s getting a lot of press and is presented out of context is that the virus can last on plastic for 72 hours—which sounds really scary. But what’s more important is the amount of the virus that remains.
It’s less than 0.1% of the starting virus material. Infection is theoretically possible but unlikely at the levels remaining after a few days. People need to know this.
While the New England Journal of Medicine study found that the COVID virus can be detected in the air for 3 hours, in nature, respiratory droplets sink to the ground faster than the aerosols produced in this study.
The experimental aerosols used in labs are smaller than what comes out of a cough or sneeze, so they remain in the air at face-level longer than heavier particles would in nature.
What is the best way I can protect myself, knowing that the virus that causes COVID-19 lives on surfaces?
You are more likely to catch the infection through the air if you are next to someone infected than off of a surface. Cleaning surfaces with disinfectant or soap is very effective because once the oily surface coat of the virus is disabled, there is no way the virus can infect a host cell. However, there cannot be an overabundance of caution. Nothing like this has ever happened before.
The CDC guidelines on how to protect yourself include:
- Clean and disinfect surfaces that many people come in contact with. These include tables, doorknobs, light switches, countertops, handles, desks, phones, keyboards, toilets, faucets, and sinks. Avoid touching high-contact surfaces in public.
- Wash your hands often with soap and water for at least 20 seconds immediately when you return home from a public place such as the bank or grocery store.
- When in a public space, put a distance of six feet between yourself and others.
- Most importantly, stay home if you are sick and contact your doctor.
There has been speculation that once the summer season arrives and the weather warms up, the virus won’t survive, but we don’t yet know if that is true. Does the weather or indoor temperature affect the survival of the COVID-19 virus on surfaces?
There is no evidence one way or the other. The virus’s viability in exposure to heat or cold has not been studied. But it does bear pointing out that the New England Journal of Medicine study was performed at about room temperature, 21-23 degrees Celsius. Read more.