Is it possible for the coronavirus to hitch a ride on a package or parcel, make its way into your mailbox, and infect you? Could the pathogen lurk on your smartphone, waiting patiently for you to put the speaker to your mouth?
While there has been no research directly answering these questions, there have been a number of recent studies looking at how long the novel coronavirus SARS-CoV-2 can survive on a range of different surfaces. One of the most definitive studies on the matter was published in The New England Journal of Medicine last week, which was broadly in line with other research into this subject.
Scientists looked to investigate how long SARS-CoV-2, as well as the genetically similar virus responsible for the SARS outbreak in the early 2000s, could remain detectable in the air and on four surfaces found in an everyday home or hospital setting at room temperature, approximately 21-23°C (70-73°F). These materials included plastic, stainless steel, copper, and cardboard, as well as how long the virus can remain suspended in the air as an aerosol.
The team found the virus was still detectable on copper up to four hours after being contaminated, up to 24 hours on cardboard, and two to three days later on plastic and stainless steel.
"If you're touching items that someone else has recently handled, be aware they could be contaminated and wash your hands,” James Lloyd-Smith, co-author of the study and UCLA professor of ecology and evolutionary biology, explained in a statement.
So, in theory, the coronavirus could remain on a cardboard parcel for about a day or a plastic smartphone case for a couple of days.
However, this is jumping to a few conclusions. Firstly, it's unclear how infectious these coronaviruses are after sitting on a dry material for three days. Secondly, the longevity of viruses on a surface can depend on a variety of factors, most notably temperature. If the virus has laid in a chilly mailbox overnight or sat on a baking hot porch all day, then the virus will have a tougher time surviving compared to sitting comfortably at room temperature.
With that said, it’s not easy to know where your package has been, nor who your delivery driver has just dropped a parcel to, so it’s impossible to fully know the risk.
Your safest bet if you receive a package is to carefully open it as soon as it’s delivered and promptly wash your hands before touching anything else. In regards to your phone, you should also try to avoid using it unless you've got clean hands. Since that's not always possible, you can give it a quick clean with alcohol wipes (just be sure not to damage the hardware and void your warranty).