Introduction
The coronavirus that causes COVID-19 mainly spreads from person to person. Transmission from person to person can happen through larger droplets from sneezes and coughs but there is also growing evidence that smaller particles called aerosols can hang in the air longer and travel farther. These aerosols may also play a part in transmission.
A variety of studies are looking at how long the virus stays alive on a variety of surfaces. It is still unclear if this increases the chance of transmission. From what we know so far – transmission from surfaces is much lower risk than person to person.
Still, it is possible (though not as likely) to catch the virus if you touch a surface or object that has the virus on it and then touch your mouth, nose, or eyes.
The coronavirus can live anywhere from hours to days on surfaces like countertops and doorknobs, however, how long it survives entirely depends on the material the surface is made from. As this virus if very new, researchers are still learning about Covid-19 and the way that it behaves. Do bear in mind that you are more likely to catch the illness from having close contact with someone who has the virus, rather than from touching a contaminated surface. One of the most important things that you can do is wash your hands when you get home.
There is still research being conducted on this topic as the virus is a new strand of COVID and therefore we know little about it, hence the consequences that we all have faced over the past few months. There are, however, a couple studies that have been conducted, looking into how long Coronavirus lives on certain surfaces.
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 was published in The Lancet. In this study, a droplet containing a set amount of virus was placed onto a surface.
For both of these studies the surfaces were at room temperature and samples were taken at different time intervals which were then used to calculate the results. It should be noted, however, that the virus was tested in laboratory conditions, therefore other environments may impact the
How Long COVID-19 Lasts on Surfaces
amount of time the virus can survive. As this is a new strand, it is difficult to test while remaining ethical and safe.
The following is a list of materials and the amount of time it is thought that the virus can remain on each material for.
- Plastic – 3-7 days
- Stainless Steel – 3-7days
- Paper – up to 4 days
- Glass – up to 4 days
- Wood – up to 2 days
- Cardboard – 24 hours
- Copper – up to 4 hours
This information goes to show that there are varied amounts of time the virus can last for on different materials, further stressing the importance of keeping surfaces clean and using cleaning products that kill COVID-19.
Healthline (2020) put together a list of objects that are included in each of the materials above that you should therefore consider cleaning or putting aside until you know they are safe to interact with. This is because some items can be easily cleaned, for example anything plastic, but others cannot, for example items made from paper.
Plastic
Many objects that we use every day are made of plastic. Some examples include, but are not 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
- Toys
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. This again stresses the importance of making sure that the items in your home are clean and shows that there is much more research needed to understand this virus.
Metal
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:
- Stainless steel
- Door handles
- Refrigerators
- Metal handrails
- Keys
- Cutlery
- Pots and pans
- Industrial equipment
- Coins
- Cookware
- Jewellery
- 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.
Paper
Some examples of common paper products include:
- Paper money
- Letters and stationery
- Magazines and newspapers
- Tissues
- 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.
Glass
Some examples of glass objects that we touch every day include:
- Windows
- Mirrors
- Drinkware
- Screens for TVs, computers, and smartphones
The Lancet article found that no virus could be detected on glass surfaces after 4 days.
Wood
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.
Cardboard
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.
Water
Coronavirus hasn’t been found in drinking water. If it does get into the water supply, your local water treatment plant filters and disinfects the water, which should kill any germs.
Fabrics
Examples: clothes, linens
There’s not much research about how long the virus lives on fabric, but it’s probably not as long as on hard surfaces.
Shoes
One study tested the shoe soles of medical staff in a Chinese hospital intensive care unit (ICU) and found that half were positive for nucleic acids from the virus. But it’s not clear whether these pieces of the virus cause infection. The hospital’s general ward, which had people with milder cases, was less contaminated than the ICU.
Skin and hair
There’s no research yet on exactly how long the virus can live on your skin or hair. Rhinoviruses, which cause colds, survive for hours. That’s why it’s important to wash or disinfect your hands, which are most likely to come into contact with contaminated surfaces.
What About Food?
According to the Centres for Disease Control and Prevention (CDC), the general group of ‘coronaviruses’ generally survive poorly on food. It should be noted, however, that you should still be careful when handling food (obviously by washing your hands thoroughly for at least 20 seconds beforehand) as the food packaging could be contaminated.
In general, it is a good rule to wash fresh fruits and vegetables thoroughly with clean water and use anti-bacterial wipes on plastic or glass food packaging items to be safe. As mentioned, you should always wash your hands when handling food. This includes:
- After handling and storing food
- Before and after prepping food
- Before eating
What You Can Do
To reduce your chance of catching or spreading the new coronavirus, clean and disinfect common surfaces and objects in your home and office every day. This includes:
- Countertops
- Tables
- Doorknobs
- Bathroom fixtures
- Phones
- Keyboards
- Remote controls
- Toilets
Use a household cleaning spray or wipe. If the surfaces are dirty, clean them first with soap and water and then disinfect them.
You can also make a bleach solution that will be good for up to 24 hours. Mix 5 tablespoons (one-third cup) of household bleach per gallon of water, or 4 teaspoons per quart of water. Never mix bleach with ammonia or another cleanser. Leave cleaners or bleach solutions on surfaces for at least 1 minute.
Keep surfaces clean, even if everyone in your house is healthy. People who are infected may not show symptoms, but they can still transmit the virus.
Wash your hands with soap and warm water for at least 20 seconds after you visit the drugstore or supermarket or bring in takeout food or a delivered newspaper.
It’s a good idea to wash fruits and vegetables under running water before you eat them. Scrub them with a brush or your hands to remove any germs that might be on the surface. If you have a weakened immune system, you might want to buy frozen or canned produce.
There’s no evidence that anyone has gotten the virus from food packaging. But if you want, you can wipe down take-out containers or grocery items and let them air dry.
Wash or disinfect reusable grocery bags after each use. Wash used fabrics often, using the warmest water that the manufacturer recommends. Dry them completely. Wear disposable gloves when handling an ill person’s laundry. Throw them away when you’re done and wash your hands.
The virus probably won’t survive the time it takes for mail or other shipped items to be delivered. The highest risk comes from the person delivering them. Limit your contact with delivery people as much as you can. You might also leave packages outside for a few hours or spray them with a disinfectant before bringing them in. Wash your hands after you handle mail or a package.
If you want, you can disinfect the soles of your shoes and avoid wearing them indoors.
CoronaVirus Research
We can pick up Covid-19 by touching surfaces contaminated with the new coronavirus, but it is now becoming clear just how long the virus can survive outside the human body in the air, on objects and fabrics.
As Covid-19 has spread, so has our fear of surfaces. There are now some familiar scenes in public places around the world – people trying to open doors with their elbows, commuters studiously surfing their way through train journeys to avoid grabbing a handle, office workers rubbing down their desks each morning.
In the areas worst hit by the new coronavirus, teams of workers in protective clothing have been dispatched to spray a fog of disinfectant in plazas, parks, and public streets. Cleaning regimes in offices, hospitals, shops and restaurants have been increased. In some cities, well-meaning volunteers even venture out at night to scrub the keypads of cash machines.
Like many respiratory viruses, including flu, Covid-19 can be spread in tiny droplets released from the nose and mouth of an infected person as they cough. A single cough can produce up to 3,000 droplets. These particles can land on other people, clothing, and surfaces around them, but some of the smaller particles can remain in the air. There is also some evidence that the virus is also shed for longer in faecal matter, so anyone not washing their hands thoroughly after visiting the toilet could contaminate anything they touch.
An alarming recent study published by researchers at Imperial College London showed that viral DNA left on a hospital bed rail in an isolation room had spread within ten hours to 18 other surfaces, including door handles, chairs in a waiting room, children’s toys and books in a play area. Although they used a virus that infects plants rather than humans as a surrogate for Sars-CoV-2, it shows just how far a virus in a droplet of liquid that lands on a bed can spread by people touching surfaces.
It is worth noting that, according to the Centre for Disease Control and Prevention (CDC), touching a surface or object contaminated with the virus and then touching one’s own face “is not thought to be the main way the virus spreads”. In May, the CDC updated its guidance to say that Covid-19 spreads “very easily” from person to person through contaminated droplets produced by others as they talk, cough, sneeze, and breath.
Even so, the CDC, the World Health Organisation, and others health authorities, have emphasised that both washing one’s hands and cleaning and disinfecting frequently touched surfaces daily are key in preventing Covid-19’s spread. The CDC’s latest guidance for how schools, restaurants and other public places can start to reopen details the need for intensified cleaning and disinfection of frequently touched surfaces such as playground equipment, door handles, bathroom taps and drinking fountains. It also admits that scientists are still learning about exactly how the virus spreads. So, although we still don’t know exactly how many cases are being caused directly by contaminated surfaces, experts advise exercising caution.
One aspect that has been unclear is exactly how long Sars-CoV-2, the name of the virus that causes the disease Covid-19, can survive outside the human body. Some studies on other coronaviruses, including Sars and Mers, found they can survive on metal, glass and plastic for as long as nine days, unless they are properly disinfected. Some can even hang around for up to 28 days in low temperatures.
Coronaviruses are well known to be particularly resilient in terms of where they can survive. And researchers are now beginning to understand more about how this affects the spread of the new coronavirus.
Neeltje van Doremalen, a virologist at the US National Institutes of Health (NIH), and her colleagues at the Rocky Mountain Laboratories in Hamilton, Montana, have done some of the first tests of how long Sars-CoV-2 can last for on different surfaces. Their study, which has been published in the New England Journal of Medicine, shows that the virus could survive in droplets for up to three hours after being coughed out into the air. Fine droplets between 1-5 micrometres in size – about 30 times smaller than the width of a human hair – can remain airborne for several hours in still air.
It means that the virus circulating in unfiltered air conditioning systems will only persist for a couple of hours at the most, especially as aerosol droplets tend to settle on surfaces faster in disturbed air.
But the NIH study found that the Sars-CoV-2 virus survives for longer on cardboard – up to 24 hours – and up to 2-3 days on plastic and stainless-steel surfaces.
The findings suggest the virus might last this long on door handles, plastic-coated or laminated worktops and other hard surfaces. Another more recent study released in May by microbiologists in Beijing, China, found that Sars-CoV-2 could survive and remain infectious on smooth surfaces including plastic, stainless steel, glass, ceramics and latex gloves for up to seven days. They found they could not obtain infectious viral particles from cotton clothing after four days and that no virus could be obtained from paper surface after five days.
The researchers at NIH, however, did find that copper surfaces tended to kill the virus in about four hours.
Although there is no data on how many virus particles will be in a single droplet coughed up by an infected person, research on the flu virus suggests smaller droplets can contain many tens of thousands of copies of the influenza virus. However, this can vary depending on the virus itself, where in the respiratory tract it is found and at what stage in the infection the person is.
The researchers did find, however, that copper surfaces tended to kill the virus in about four hours
On clothing and other surfaces harder to disinfect, it is not yet clear how long the virus can survive. The absorbent natural fibres in cardboard, however, may cause the virus to dry up more quickly than on plastic and metal, suggests Vincent Munster, head of the virus ecology section at Rocky Mountain Laboratories and one of those who led the NIH study.
“We speculate due to the porous material, it desiccates rapidly and might be stuck to the fibres,” he says. Changes in temperature and humidity may also affect how long it can survive, and so may explain why it was less stable in suspended droplets in the air, as they are more exposed. “[We’re] currently running follow-up experiments to investigate the effect of temperature and humidity in more detail.”
The ability of the virus to linger for so long only underlines the importance of hand hygiene and cleaning of surfaces, according to Munster.
Products to Use
Similarly to when cleaning your hands, soap and water is one of the most effective methods to cleaning surfaces. According to Which.co.uk (2020), Dr Primrose Freestone, Associate Professor in Clinical Microbiology at the University of Leicester explains:
‘COVID-19 is an enveloped RNA (ribonucleic acid) virus, meaning that proteins and lipids are part of its structure.
Therefore, detergents by themselves – such as soap and even washing-up liquid – work very well at disrupting the virus structure by dissolving the lipids, which in turn inactivates the virus by stopping it binding to our cells.’
An alcohol-based hand sanitiser with at least 60% alcohol works in a similar way, dissolving lipids in the virus coating.
We’ve mentioned cleaning and disinfecting previously, the best way to make sure that germs are removed from the home to stop them from spreading is by using cleaning products that kill COVID-19, and then following up by disinfecting the surface.
Antibacterial Products
There are many products in the store that are marked as antibacterial but will not work against a virus like COVID-19. They need to contain at least a 60% alcohol to protect against Coronavirus.
When buying disinfectant products such as sprays or wipes, then you will need to check it first to see if they work against viruses as well as bacteria. Normal household cleaners would have been perfectly fine to use pre-pandemic, however, to make sure that the house is safe from the virus and spread of the germs, it is crucial to check that they work against the virus.
Tips for Cleaning Different Surfaces
Here we are sharing the NHS tips to preventing germs from spreading on different surfaces or objects in the home. We have talked about the cleaning products that kill COVID-19, how they should be used (as per instructions), and how to make and use homemade cleaning products. Now, we are discussing the simple tips to follow to prevent the spread of germs which is particularly important during the fight against Coronavirus.
Toilets
- Keep the U-bend and toilet bowl clean by flushing after each use
- Use a toilet cleaner and brush every few days
- Limescale should be regularly removed using a descaling product
- Keep the toilet seat, handle, and rim clean by using a disinfectant
Baths, sinks and showers
- Clean frequently, if they are used regularly
- Use disinfectant if they have been used by someone who is ill
Kitchen
- Ensure food-preparation surfaces are clean before use
- Use separate chopping boards for uncooked food – such as raw meat – and food that does not need cooking, like salad leaves
- Wash and dry your hands after handling foods such as raw meat
- Clean surfaces immediately after use
Floors
- Clean floors regularly with warm water and detergent to remove visible dirt
- If soiled, the floor should be cleaned using a disposable cloth and warm water, then disinfected – make sure the floor is dry before allowing children on it
Carpet and soft furnishings
- Steam cleaning is effective against germs on carpets and furnishings
- Curtains can be cleaned by laundering or disinfected by steam cleaning
Electronics
- Follow cleaning instructions
- Consider buying wipeable covers
- If no manufacturer guidance is available, consider the use of alcohol-based wipes or sprays containing at least 70% alcohol to disinfect touch screens.
- Dry surfaces thoroughly
Toys
- Clean hard or plastic toys by washing them and putting them away once they are clean and dry
- Some soft toys can be cleaned in the washing machine
Laundry
- Wash your hands after handling dirty laundry
- All underwear, towels and household linen should be washed at 60C (140F) or at 40C (104F) with a bleach-based laundry product to prevent germs from spreading
- Do not leave laundry in the washing machine – any remaining germs can multiply rapidly
Waste disposal
- Foot-operated bins are more hygienic because they reduce the risk of getting germs onto your hands from touching the bin lid
- Always wash your hands after handling waste material
- Throw rubbish away carefully to avoid attracting vermin and insects
