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Do you still need to disinfect packages? Analyzing new CDC advice

Over a year ago, we told you how to disinfect packages from COVID-19. In the interim, some doctors and scientists became aghast that people were doing this. The CDC offered conflicted and confusing advice, which we happily fact checked, and the CDC withdrew. Many of you are still following our package disinfection advice.

Now the CDC has once again updated its information about COVID-19 surface transmission, this time with an actual figure of what they mean when they say that surface transmission is rare: less than 1 in 10,000 infections.

Does that mean disinfecting packages is pointless? The community was discussing this in the forum, so here’s our take:

  • The CDC’s advice is contradictory and confusing, but the chance of COVID-19 surface transmission indeed seems to be tiny.
  • Ultimately, it’s about the risks you’re willing to take. If you’re eating in restaurants and going to Disney World, there probably isn’t much point in disinfecting packages.
  • However, if you’re taking every possible precaution and have a vulnerable household member, disinfecting packages might be a worthy tool in your arsenal.
  • Sunlight seems far more effective against the virus than originally thought.

The advice is still confusing

First, a couple of things:

  • Surface transmission is not and has never been the primary vector of COVID-19 transmission. In the original package disinfection article, we said that your biggest threat is the delivery driver (though outdoor transmission also seems to be low), not the delivery itself.
  • When the CDC report says “fomite,” they mean contaminated surfaces. You can replace the word “fomite” with “surface” in your head if that makes it easier to read.

Let’s identify a few of the ways the new CDC advice is still confusing:

  • It simultaneously says “it is not clear what proportion of SARS-CoV-2 infections are acquired through surface transmission” while also saying “these studies suggest that the risk of SARS-CoV-2 infection via the fomite transmission route is low, and generally less than 1 in 10,000.” Which is it?
  • The report says, “Surface disinfection has been shown to be effective for preventing secondary transmission of SARS-CoV-2 between an infected person and other people within households. However, there is little scientific support for routine use of disinfectants in community settings, whether indoor or outdoor, to prevent SARS-CoV-2 transmission from fomites.” This might seem confusing, but the spirit of what they’re saying is it can be helpful on surfaces inside your house, such as a bathroom door knob you’re sharing with a sick person.
  • The report says, “When focused on high-touch surfaces, cleaning with soap or detergent should be enough to further reduce the relatively low transmission risk from fomites in situations when there has not been a suspected or confirmed case of COVID-19 indoors,” but also says, “To substantially inactivate SARS-CoV-2 on surfaces, the surface must be treated with a disinfectant product registered with the Environmental Protection Agency’s (EPA’s) List N or technology that has been shown to be effective against the virus.” So do you need mere soap and water or do you need special disinfectants and technology?

It very much reads like a statement drafted by a committee of conflicting interests. However, we’ll let the officials and managers tease all of this out to determine the disinfection policies at their facilities. The chief question is if you still need to disinfect packages.

Do you need to disinfect packages?

Short answer: probably not. But as with everything related to COVID-19, you have to determine the risk profile you’re comfortable with.

We’ve had about 31 million cases of COVID-19 in the United States. Taking the 1 in 10,000 figure at face value, that’s about a 0.01% chance of catching COVID-19 through a surface. So out of 31 million infections, you can estimate that about 3,100 of those infections were caused by surface transmission.

So, as doctors and scientists have said, there’s a chance of surface transmission, albeit a tiny one. Additionally, the CDC report reiterates what we’ve known for a year: that SARS-CoV-2 survives much longer on non-porous surfaces than porous ones. However, exact figures are elusive. The general guidance has been 24 hours on cardboard, 72 hours on nonporous surfaces, though the CDC report says that the virus can sometimes dissipate within minutes on porous surfaces.

But packages are much more than just cardboard. There’s usually at least a small amount of tape on the outside. And then there’s the contents inside, which are usually nonporous. We recommended quarantining packages for three days before opening them. Again, this comes down to how much of a chance you’re willing to take.

These are my updated guidelines:

  • If you’re generally living life as if everything is normal, there’s no point in disinfecting packages.
  • If the most high-risk people in your household have been fully vaccinated, there probably isn’t much benefit from disinfecting packages.
  • If you have unvaccinated high-risk members in your household and you’re taking every possible precaution to prevent infection, disinfecting packages might be worthwhile.
  • In any case, frequent hand washing and/or hand sanitizing are good practices, especially after handling foreign surfaces. Be sure to use a reputable hand sanitizer.

However, you may not need to spray disinfectant at all. New studies indicate that SARS-CoV-2 is much more sensitive to sunlight than originally thought.

Sunlight vs. COVID-19

In our original guide to disinfecting packages, the thinking at the time was that sunlight was not effective against SARS-CoV-2. However, recent work by scientists at UC Santa Barbara have brought that into question.

In lab experiments, solar radiation deactivated the virus in about 10 to 20 minutes. This is much faster than had previously been theorized — anywhere from 3 to 8 times faster. The scientists were baffled, because the sensitivity of SARS-CoV-2 appears to exceed the sensitivity of any other known virus to UV-B rays.

The current hypothesis is that UV-A, another component of natural sunlight, has a greater effect than anticipated. It’s long been known that UV-C, which is not part of natural sunlight, is effective against the virus, but is also a hazard to humans.

In any case, it seems that sunlight is thankfully more effective against SARS-CoV-2 than originally thought. So if you’re concerned about a package or the contents therein, a half-hour or so in the sun might be enough to minimize the already small risk of catching COVID from a package. Rotate the package to make sure all sides are “cooked,” and, if you can, open the box and let the inside of the box and all sides of the contents bask in sunlight.

An open box of film sitting in the sun


    • Cia

      I don’t think there’s any way to know for sure if you were infected by fomite transmission. Even if you were conscientious about wearing masks, etc., there would be a chance that some virus got through the edges of the mask when a carrier emitted virus nearby. Or that a family member had an asymptomatic, undiagnosed case. You’d have to rule out all possibility of droplet or aerosol transmission, which few people other than Rapunzel could do.

      I agree with your saying it depends on your individual risk tolerance. We haven’t disinfected any packages. But it seems likely that if an infected delivery man sneezed on a package right before he left it at your door and you picked it up, etc., I think under the right circumstances you could be infected. But it seems unlikely and it would probably be a low viral load.

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    • woodrow

      I had to retrain myself last year to let packages sit.  Just because my Amazon arrived, doesn’t mean I have to open it right then.  So I’ve been letting the mail and packages sit for 24 hrs before opening them. I don’t disinfect, just let the viruses, if there are any, die on the vine.  Groceries pretty much the same, except for perishables, which got wiped down or dishsoap-bathed briefly before refrigerating.  But since our vaccinations, have dropped the above behaviors re: mail and packages.  If a supervariant comes along, will probably reinstitute all. 

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    • Bigwig

      Thanks for the update.  I am the one who entered the original forum post you mentioned above.  I’m still handing packages, mail, and groceries carefully using either disinfecting wipes or time.  It’s good to know that sunlight can work as well but it seems like more work than I am doing now.  There are still a number of unknowns and i’d rather err on the side of caution.  Since i’m living in the state with the current highest rate of COVID-19 infections, I don’t think I will be relaxing my protocols any time soon.

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    • MarcusAurelius

      This is reasonable analysis, Josh. Thanks.

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