WHEN SARS-CoV-2 first surfaced in the winter of 2020, there were many questions about how long the virus lived on surfaces. Local and international regulatory organizations provided guidelines and cleaning protocols to ensure surfaces were safe.1,2 As another wave of COVID-19 affects individuals around the globe, this article reviews the evidence related to how long the virus may live on common surfaces.

Transmission and prevention

SARS-CoV-2, the virus that causes COVID-19, is most commonly transmitted person-to-person through respiratory droplets that are released when talking, laughing, sneezing, singing, or coughing.3 According to the CDC, the virus may spread through the air between individuals in enclosed spaces with poor ventilation; less commonly, it may be transmitted when individuals touch a surface or object with the virus on it, then touch their mouth, nose, or eyes.4 For example, a 2020 review found the persistence of SARS-CoV-1 and SARS-CoV-2 to be significantly lower on copper surfaces, latex, and less porous fabrics in contrast with zinc, glass, metal surfaces such as steel, and more porous fabrics.5

This finding was corroborated in a separate 2020 study, which demonstrated that infectious SARS-CoV-2 may be recovered from nonporous surfaces such as glass, paper and polymer banknotes, stainless steel, and vinyl for 28 days at a temperature of 20[degrees] C (68[degrees] F) and 50% relative humidity.6 The durability of the virus decreased as the temperature increased, even when the humidity remained constant. For example, the virus could be found on stainless steel, polymer banknotes, and glass for 7 days and on vinyl for 3 days at 30[degrees] C (86[degrees] F) temperatures. Notably, it lasted less than 48 hours on nonporous surfaces at 40[degrees] C (104[degrees] F) temperatures. Similarly, the virus survived a much shorter time on porous materials such as cotton and paper banknotes. At 20[degrees] C (68[degrees] F) temperatures, the virus was found on cotton for 5.5 days and on paper banknotes for 9.1 days. At 30[degrees] C (86[degrees] F) temperatures, it was detected for 3 days on cotton and for 4.9 days on paper banknotes. At 40[degrees] C (104[degrees] F) temperatures, it was not detected after 24 hours on cotton and after 48 hours on paper banknotes.6

The study also examined the persistence of SARS-CoV-2 on glass surfaces, demonstrating that the virus can remain on glass surfaces for 22 days at 22[degrees] C (71.6[degrees] F) and 7 days at 35[degrees] C (95[degrees] F).6 As such, cleaning touchscreen devices such as cell phones and tablets is crucial.

An early report detailing onsite detection of SARS-CoV-2 in healthcare facilities indicated that the virus may contaminate any surface in a hospital room. The most frequently contaminated surfaces included the ECG fingertip, bed rails, and the door handle to the bathroom.7 These results provided information for guidance related to routine disinfecting practices.

One concerning finding has been SARS-CoV-2 contamination in bathrooms, specifically associated with toilets. For example, one 2021 study found positive viral samples on the inside of the bathroom door handle, as well as the toilet seat, seat cover, handle, and even the ceiling exhaust grill.8 Toilets are typically housed in small rooms and often shared with others in healthcare facilities, work sites, offices, and residential homes. Further, the virus may be aerosolized by toilet flushing and subsequently contaminate the surrounding surfaces.9 As such, proper hygiene and cleaning in both public and private bathrooms is crucial. Risks associated with viral transmission in bathrooms may be mitigated via hand hygiene practices recommended by the CDC.10

Currently, no evidence indicates that eating or handling food or drinking water spreads SARS-CoV-2, but daily cleaning and disinfecting of frequently touched surfaces is vital.3 These include tables, doorknobs, light switches, countertops, handles, desks, phones, keyboards, toilets, faucets, and sinks. The virus can be killed via ready-to-use sprays, concentrates, and disinfectant wipes that have been approved by the Environmental Protection Agency.11

Guidance on keeping safe from COVID-19 is available and can be shared with patients and their families. For example, gloves are unnecessary when running errands, as they will not prevent transmission. This guidance focuses on hand hygiene recommendations, such as washing hands with soap and water for at least 20 seconds before leaving the house and after returning home and using hand sanitizer when in and out of businesses. Handwashing is also important after putting away groceries and handling takeout containers, although there is no need to disinfect these items. Similarly, the mail does not need to be quarantined, as handwashing after handling these envelopes or packages is the best practice.12

Moving forward

The best way to prevent the spread of COVID-19 is to wear a mask, maintain hand hygiene and social distancing, and avoid those who are ill. Because many individuals wear their masks incorrectly, the CDC offers guidance on the proper way to wear a mask for consumers.13 Children younger than 2 years, individuals who experience trouble breathing, and those who cannot remove their mask without assistance should not wear face coverings.

Moving forward, vaccines will assist the US in reaching herd immunity.14 In the meantime, nurses must continue to educate patients, families, and communities about public health measures that can limit the spread of the virus, such as wearing a face covering and maintaining social distancing, and encourage patients to receive any available vaccine.

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