When a person sneezes or has a wet cough around you, does that sickness still stay in the air on on the surface? This question is more important than ever with the new coronavirus. The virus that causes coronavirus disease 2019 (COVID-19) is for several hours to days in aerosols and on surfaces, according to a new study from National Institutes of Health, CDC, UCLA and Princeton University scientists in The New England Journal of Medicine.
The scientists found that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was detectable:
– in aerosols for up to three hours
– up to four hours on copper
– up to 24 hours on cardboard
– up to two to three days on plastic
– up to 2 days on stainless steel
The results provide key information about the stability of SARS-CoV-2, which causes COVID-19 disease, and suggests that people may acquire the virus through the air and after touching contaminated objects. The study information was widely shared during the past two weeks after the researchers placed the contents on a preprint server to quickly share their data with colleagues.
The NIH scientists, from the National Institute of Allergy and Infectious Diseases’ Montana facility at Rocky Mountain Laboratories, compared how the environment affects SARS-CoV-2 and SARS-CoV-1, which causes SARS. SARS-CoV-1, like its successor now circulating across the globe, emerged from China and infected more than 8,000 people in 2002 and 2003. SARS-CoV-1 was eradicated by intensive contact tracing and case isolation measures and no cases have been detected since 2004. SARS-CoV-1 is the human coronavirus most closely related to SARS-CoV-2. In the stability study the two viruses behaved similarly, which unfortunately fails to explain why COVID-19 has become a much larger outbreak.
The NIH study attempted to mimic virus being deposited from an infected person onto everyday surfaces in a household or hospital setting, such as through coughing or touching objects. The scientists then investigated how long the virus remained infectious on these surfaces.
The scientists highlighted additional observations from their study:
If the viability of the two coronaviruses is similar, why is SARS-CoV-2 resulting in more cases? Emerging evidence suggests that people infected with SARS-CoV-2 might be spreading virus without recognizing, or prior to recognizing, symptoms. This would make disease control measures that were effective against SARS-CoV-1 less effective against its successor.
In contrast to SARS-CoV-1, most secondary cases of virus transmission of SARS-CoV-2 appear to be occurring in community settings rather than healthcare settings. However, healthcare settings are also vulnerable to the introduction and spread of SARS-CoV-2, and the stability of SARS-CoV-2 in aerosols and on surfaces likely contributes to transmission of the virus in healthcare settings.
So how do you clean?
The US Centers for Disease Control and Prevention has said that the new coronavirus is thought to spread mainly by respiratory droplets, such as droplets in a cough or sneeze.
“It may be possible that a person can get COVID-19 by touching a… surface or object that has the virus on it and then touching their own mouth, nose, or possibly their eyes, but this is not thought to be the main way the virus spreads,” according to the CDC’s website.
In its guidelines on disinfecting a home if someone is sick, the CDC encourages cleaning and disinfecting frequently touched surfaces and objects, such as tables, countertops, light switches, doorknobs and cabinet handles.
Cleaning would be with soap and water, and disinfecting would be with certain bleach solutions or alcohol solutions described on the CDC’s website, or EPA-registered disinfectants.
The findings affirm the guidance from public health professionals to use precautions similar to those for influenza and other respiratory viruses to prevent the spread of SARS-CoV-2:
– Avoid close contact with people who are sick.
– Avoid touching your eyes, nose, and mouth.
– Stay home when you are sick.
– Cover your cough or sneeze with a tissue, then throw the tissue in the trash.