BySamuel Volkin

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.

Machamer: What's getting a lot of press and is presented out of context is that the virus can last on plastic for 72 hourswhich 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.

What you need to know

Resources and updates for the Johns Hopkins community, including travel guidance, information on university operations, and tips for preventing the spread of illness

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.

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:

Coverage of how the COVID-19 pandemic is affecting operations at JHU and how Hopkins experts and scientists are responding to the outbreak

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.

SARS-CoV-2 behaves like a typical respiratory coronavirus in the basic mechanisms of infection and replication. But several mutations allow it to bind tighter to its host receptor and increase its transmissibility, which is thought to make it more infectious.

The New England Journal of Medicine study suggests that the stability of SARS-CoV-2 is very similar to that of SARS-CoV1, the virus that caused the 2002-2003 SARS global outbreak. But, researchers believe people can carry high viral loads of the SARS-CoV-2 in the upper respiratory tract without recognizing any symptoms, allowing them to shed and transmit the virus while asymptomatic.

View post:
How long can COVID-19 live on surfaces? - The Hub at Johns Hopkins