How persistent is the SARS-CoV-2 virus on different surfaces and in various temperatures?
Summary:
- SARS-CoV-2 is more persistent in lower temperatures, while it decays faster when exposed to higher temperatures.
- At room temperature, the SARS-CoV-2 virus can survive for over a week when in conditions perfect for its survival.
- Frequent washing or disinfecting your hands is crucial to stopping the transfer of the virus.
The world is still struggling with the COVID-19 pandemic. There are currently (22.04.2020) almost 2’500’000 infected people with over 160’000 deaths related to SARS-CoV-2 infection [1]. Fortunately, there is a light at the end of the tunnel, as few countries, like Denmark, Austria, Norway, Germany, and Switzerland took the first steps to ease the current lockdown [2]. They were able to do so as the number of cases started to decrease in these countries.
We cannot completely relax yet and we still have to follow official guidelines to slow down the spread of the SARS-CoV-2 virus. It is mainly transmitted from an infected person through droplets generated during sneezing and coughing [3]. We already described the persistence of the SARS-CoV-2 in these droplets on four different surfaces [4]:
- Plastic up to 72 hours
- Stainless steel up to 48 hours
- Cardboard up to 24 hours
- Copper up to 4 hours
These results were generated by a group led by Neeltje van Doremalen. In their study, they were able to create conditions very close to the every-day situation. Unfortunately, these results do not give us a full spectrum of information we may need in our daily lives.
A separate study group led by Alex Chin performed experiments that covered a broader spectrum of conditions [5]. First of all, they presented survival of the virus in different temperatures, but in otherwise perfect conditions for virus survival:
- 4 °C more than 14 days
- 22 °C more than 7 days
- 37 °C less than 2 days
- 56 °C less than 30 minutes
- 70 °C less than 5 minutes
These results mean that putting products that had contact with the SARS-CoV-2 virus in the fridge will increase the time of its survival. On the other hand, we don’t have to worry about the infection with clothes after washing in high temperatures or with food after cooking or baking.
The group led by Alex Chin also tested how long the virus will survive when introduced to various kinds of surfaces that we may have contact with during our daily activities. The presented experiment was performed at 22 °C in the humidity of 65%:
- Paper less than 3 hours
- Tissue paper less than 3 hours
- Wood less than 2 days
- Cloth less than 2 days
- Glass less than 4 days
- Banknote less than 4 days
- Surgical mask, inner layer less than 7 days
- Surgical mask, outer layer 7 days
It is important to remember that these results were obtained using conditions more in favor of the virus’s survival. Hence, in everyday situations, this time will be shorter. Nevertheless, it is still imperative to often wash or disinfect our hands during COVID-19 pandemic to avoid the spread of the infection [3]. Moreover, we should always restrain from touching our faces when outdoors and, most importantly, we should follow official guidelines.
References:
- WHO, Coronavirus disease 2019 (COVID-19) Situation Report – 92. 2020, World Health Organization.
- Brandon, S., These European countries are starting to lift their coronavirus lockdowns, in World Economic Forum. 2020.
- WHO, Water, sanitation, hygiene, and waste management for the COVID-19 virus. 2020, World Health Organization.
- van Doremalen, N., et al., Aerosol and Surface Stability of SARS-CoV-2 as Compared with SARS-CoV-1. N Engl J Med, 2020.
- Chin, A.W.H., et al., Stability of SARS-CoV-2 in different environmental conditions. The Lancet Microbe, 2020.