In late 2019, a new coronavirus began circulating in humans. This virus, called SARS-CoV-2, causes the illness known COVID-19.
SARS-CoV-2 can spread easily from person to person. It mainly does this through respiratory droplets that are produced when someone with the virus talks, coughs, or sneezes near you and the droplets land on you.
It’s possible that you could acquire SARS-CoV2 if you touch your mouth, nose, or eyes after touching a surface or object that has the virus on it. However, this is not thought to be the main way that the virus spreads.
How long does the coronavirus live on surfaces?
Research is still ongoing into many aspects of SARS-CoV-2, including how long it can live on various surfaces. So far, two studies have been published on this topic. We’ll discuss their findings below.
The first study was published in the New England Journal of Medicine (NEJM). For this study, a standard amount of aerosolized virus was applied to different surfaces.
The second study was published in The Lancet. In this study, a droplet containing a set amount of virus was placed onto a surface.
In both studies, the surfaces to which the virus had been applied were incubated at room temperature. Samples were collected at different time intervals, which were then used to calculate the amount of viable virus.
Keep in mind: Although SARS-CoV-2 can be detected on these surfaces for a particular length of time, the viability of the virus, due to environmental and other conditions, is not known.
Many objects that we use every day are made of plastic. Some examples include, but aren’t limited to:
- food packaging
- water bottles and milk containers
- credit cards
- remote controls and video game controllers
- light switches
- computer keyboards and mouse
- ATM buttons
The NEJM article detected the virus on plastic for up to 3 days. However, researchers in the Lancet study found that they could detect the virus on plastic for longer — up to 7 days.
Metal is used in a wide variety of objects we use every day. Some of the most common metals include stainless steel and copper. Examples include:
- door handles
- metal handrails
- pots and pans
- industrial equipment
- electrical wires
While the NEJM article found that no viable virus could be detected on stainless steel after 3 days, researchers for the Lancet article detected viable virus on stainless steel surfaces for up to 7 days.
Investigators in the NEJM article also assessed viral stability on copper surfaces. The virus was less stable on copper, with no viable virus detected after only 4 hours.
Some examples of common paper products include:
- paper money
- letters and stationery
- magazines and newspapers
- paper towels
- toilet paper
The Lancet study found that no viable virus could be found on printing paper or tissue paper after 3 hours. However, the virus could be detected on paper money for up to 4 days.
Some examples of glass objects that we touch every day include:
- screens for TVs, computers, and smartphones
The Lancet article found that no virus could be detected on glass surfaces after 4 days.
Some cardboard surfaces that you may come into contact with include objects like food packaging and shipping boxes.
The NEJM study found that no viable virus could be detected on cardboard after 24 hours.
The wooden objects that we find in our homes are often things like tabletops, furniture, and shelving.
Researchers in the Lancet article found that viable virus from wood surfaces could not be detected after 2 days.
Can temperature and humidity affect the coronavirus?
Viruses can definitely be impacted by factors like temperature and humidity. According to the Centers for Disease Control and Prevention (CDC), most coronaviruses survive for a shorter time at higher temperatures and humidity levels.
For example, in one observation from the Lancet article, SARS-CoV-2 remained very stable when incubated at 4°C Celsius (about 39°F).
However, it was rapidly inactivated when incubated at 70°C (158°F).
What about clothing, shoes, and floors?
The stability of SARS-CoV-2 on cloth was also tested in the Lancet article mentioned earlier. It was found that viable virus couldn’t be recovered from cloth after 2 days.
Generally speaking, it’s probably not necessary to wash your clothes after every time you go out. However, if you’ve been unable to maintain proper physical distance from others, or if someone has coughed or sneezed near you, it’s a good idea to wash your clothes.
A study in Emerging Infectious Diseases assessed which surfaces in a hospital were positive for SARS-CoV-2. A high number of positives were found from floor samples. Half of the samples from the shoes of ICU workers also tested positive.
It’s unknown how long SARS-CoV-2 can survive on floors and shoes. If you’re concerned about this, consider removing your shoes at your front door as soon as you get home. You can also wipe the soles of your shoes with a disinfecting wipe after going out.
What about food and water?
Can the new coronavirus survive in our food or drinking water? Let’s take a closer look at this topic.
Can the coronavirus survive on food?
The CDC notes that coronaviruses, as a group of viruses, generally survive poorly on food products and packaging. However, they do acknowledge that you should still be careful while handling food packaging that could be contaminated.
According to the Food and Drug Administration (FDA), there are currently no reports that food or food packaging is associated with SARS-CoV-2 transmission. They also note that it’s still important to follow proper food safety practices.
It’s always a good rule of thumb to wash fresh fruits and vegetables thoroughly with clean water, particularly if you plan to eat them raw. You may also want to use disinfecting wipes on plastic or glass food packaging items that you’ve purchased.
It’s important to wash your hands thoroughly with soap and warm water in food-related situations. This includes:
- after handling and storing groceries
- before and after preparing food
- before eating
Can the coronavirus live in water?
It’s unknown exactly how long SARS-CoV-2 can survive in water. However, a study from 2009 investigated the survival of a common human coronavirus in filtered tap water.
This study found that coronavirus levels dropped by 99.9 percent after 10 days in room temperature tap water. The coronavirus that was tested was more stable at lower water temperatures and less stable at higher temperatures.
So what does that mean for drinking water? Remember that our water systems treat our drinking water before we drink it, which should inactivate the virus. According to the CDC, SARS-CoV-2 hasn’t been detected in drinking water.
Is the coronavirus still viable when it’s on a surface?
Just because SARS-CoV-2 is present on a surface doesn’t mean that you will contract it. But why exactly is this?
Enveloped viruses like coronaviruses are very sensitive to conditions in the environment and can quickly lose stability over time. That means that more and more of the viral particles on a surface will become inactive as time passes.
For example, in the NEJM stability study, viable virus was detected on stainless steel for up to 3 days. However, the actual amount of virus (titer) was found to have dropped drastically after 48 hours on this surface.
However, don’t drop your guard just yet. The amount of SARS-CoV-2 that’s needed to establish an infection is still currently unknown. Because of this, it’s still important to exercise caution with potentially contaminated objects or surfaces.
How to clean surfaces
Because SARS-CoV-2 can live on various surfaces for several hours up to several days, it’s important to take steps to clean areas and objects that may come into contact with the virus.
So how can you effectively clean the surfaces in your home? Follow the tips below.
What should you clean?
Focus on high-touch surfaces. These are things that you or others in your household touch frequently during your daily activities. Some examples include:
- handles on appliances, like the oven and refrigerator
- light switches
- faucets and sinks
- tables and desks
- staircase railings
- computer keyboards and computer mouse
- handheld electronics, such as phones, tablets, and video game controllers
Clean other surfaces, objects, and clothes as needed or if you suspect they’ve been contaminated.
If possible, try to wear disposable gloves while cleaning. Be sure to throw them away as soon as you’re done.
If you don’t have gloves, just be sure to wash your hands thoroughly with soap and warm water after you’re done cleaning.
What are the best products to use for cleaning?
According to the CDC, you can use household cleaning products or EPA-registered disinfectants to clean household surfaces. Follow the directions on the label and only use these products on surfaces that they’re appropriate for.
Household bleach solutions can also be used when appropriate. To mix your own bleach solution, the CDC recommends using either:
- 1/3 cup of bleach per gallon of water
- 4 tablespoons of bleach per quart of water
Use care while cleaning electronics. If the manufacturer’s instructions aren’t available, use an alcohol-based wipe or a 70 percent ethanol spray to clean electronics. Be sure to dry them thoroughly so liquid doesn’t accumulate inside the device.
When doing laundry, you can use your regular detergent. Try to use the warmest water setting that’s appropriate for the type of clothes you’re washing. Allow washed clothes to dry completely before putting them away.
The bottom line
A few studies have been performed on how long the new coronavirus, known as SARS-CoV-2, can live on surfaces. The virus persists the longest on plastic and stainless steel surfaces. It’s less stable on cloth, paper, and cardboard.
We don’t know yet how long the virus can live in food and water. However, there have been no documented cases of COVID-19 that are associated with food, food packaging, or drinking water.
Even though SARS-CoV-2 can become inactivated in hours to days, the exact dose that can lead to an infection still isn’t known. It’s still important to maintain proper hand hygiene and to appropriately clean high-touch or potentially contaminated household surfaces.