Originally published 2020-05-04.
Leaving your shoes at the door is a sensible, low-cost habit, but shoes were never a major route for catching COVID-19. In spring 2020 several health specialists suggested keeping outdoor footwear outside, and one widely shared claim said the coronavirus could live on shoes for five days. No study had measured that. What research did show is that the virus's genetic material could be found on floors and on the soles of hospital staff, and that live virus survived for up to about three days on some hard surfaces in the lab. The main risk always came from breathing in virus from other people.
So the short answer is: a shoes-off home is a good idea for general cleanliness, and it did little harm during the pandemic, but it was never a substitute for the measures that mattered most. Here is how the advice arose and what the evidence actually says.
Where the "five days on shoes" claim came from
In late March 2020, HuffPost published a piece in which several US doctors and public health specialists discussed whether shoes could carry the new coronavirus indoors. Family physician Georgine Nanos of San Diego pointed out that footwear worn in crowded places such as offices, shops and public transport is more likely to pick up contamination. Infectious disease specialist Mary E. Schmidt of Virginia mentioned research suggesting coronaviruses could last several days on synthetic materials, and public health specialist Carol Winner of Kansas City advised keeping shoes in a garage or by the front door so they would not be walked through the house.
The article was quickly republished by other outlets, and the cautious "may survive" turned into a confident "survives on shoes for five days". In reality no published study at that time had tested shoe soles for live SARS-CoV-2 over several days. The five-day figure appears to have been borrowed from older laboratory work on other coronaviruses on various surfaces.
What the research actually showed
Laboratory survival on surfaces
The best-known early study, published in the New England Journal of Medicine in March 2020 by Neeltje van Doremalen and colleagues, sprayed the virus onto different materials under controlled conditions. Viable virus could be detected for up to 72 hours on plastic and stainless steel, for a shorter time on cardboard, and only for a few hours on copper. The amount of live virus fell steeply over that time.
Those experiments used large amounts of virus in ideal conditions. They show what is possible, not what typically happens on a busy pavement in sunlight.
Shoe soles in a Wuhan hospital
The one study that did look at shoes came from Huoshenshan Hospital in Wuhan and was published in the US CDC journal Emerging Infectious Diseases in 2020. Researchers swabbed floors and objects in an intensive care unit and a general COVID-19 ward. About half of the swabs taken from medical staff's shoe soles tested positive, and so did 7 of 10 floor samples in the ICU.
Two caveats matter. First, the tests detected viral RNA, the genetic material, not necessarily live, infectious virus. Second, this was a ward full of seriously ill COVID-19 patients, not a supermarket or a street. The authors recommended disinfecting shoe soles before leaving those wards, which made sense for hospital staff, but the findings did not show that shoes were spreading infection in homes.
How COVID-19 really spreads
As the pandemic went on, the picture became clearer. SARS-CoV-2 spreads mainly through the air, in droplets and smaller aerosol particles that people breathe out when they talk, cough, sing or simply breathe, especially in crowded, poorly ventilated indoor spaces. Later reviews concluded that infection from touching contaminated surfaces, known as fomite transmission, is possible but uncommon, and becomes very rare where ordinary cleaning is done.
Shoes are an even weaker link in that chain. For the virus to infect you from a sole, it would need to survive the journey, be transferred to your hands, and then reach your eyes, nose or mouth before it degraded. Each step reduces the risk.
Good reasons to keep a shoes-off home anyway
Even if shoes were not a big COVID-19 risk, there are other reasons to leave them at the door, and many households in Asia, Scandinavia and elsewhere have done so for generations. Soles bring in mud, road grit, pollen, animal droppings and traces of pesticides or lead dust from soil. That matters most in homes with crawling babies, toddlers or pets, who spend a lot of time on the floor.
Melbourne environmental scientist Nicole Bijlsma, who has written about healthy homes, has long recommended leaving shoes outside or just inside the entrance for exactly this reason: they are a simple way to cut down on dust and allergens indoors.
A few practical ideas make the habit easy:
- Place a shoe rack and a sturdy doormat at the main entrance.
- Keep a pair of clean indoor slippers for each person, plus a spare pair for guests.
- Wipe hard-soled or leather shoes with soapy water or a household cleaner now and then; many canvas trainers can go in the washing machine on a gentle cycle (check the label).
- If removing shoes is hard for someone with mobility issues, a good doormat still removes much of the dirt.
Don't over-sanitise your home
Bijlsma also warned against going too far. Spraying every surface with strong disinfectants kills harmless and useful microbes along with harmful ones. As she told the Daily Mail, "The conundrum is that bacteria are critical for humans." Her argument was that hospital-grade cleaning belongs in hospitals and in homes caring for very vulnerable people, while ordinary households are better served by regular cleaning with soap and water.
This fits wider advice from public health agencies: clean frequently touched surfaces regularly, and disinfect when someone in the house is ill. Mixing products, especially bleach with ammonia or acids, can release toxic gases, so stick to one product at a time and ventilate the room.
What protected people most
Throughout the pandemic, the measures with the strongest evidence were not about shoes at all:
- Vaccination, once available, greatly reduced the risk of severe illness.
- Good ventilation and spending time outdoors rather than in crowded indoor rooms.
- Staying home when sick and testing when symptoms appeared.
- Well-fitting masks in crowded indoor settings during waves of infection.
- Regular handwashing and coughing or sneezing into your elbow.
Taking your shoes off at the door is a pleasant, tidy habit with real benefits for allergies and household dirt. Just keep it in perspective: when it comes to respiratory viruses, the air you share with others matters far more than the ground you walk on. If you have specific health concerns, talk to a doctor.
Sources: van Doremalen et al., NEJM 2020; CIDRAP on the Huoshenshan Hospital study (Emerging Infectious Diseases); Wikipedia: Fomite; HuffPost Australia (2020); Daily Mail: Nicole Bijlsma.
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