COVID-19 and Groceries

Do you need to disinfect your groceries to protect yourself from the coronavirus? Can the virus be found on the surface of an inanimate object (also called fomites, from the Latin word for tinder) like the packaging of food at the grocery store? And, if the virus can be found there, can it make you sick? Here’s everything we currently know about COVID-19 and Groceries. (And we will give you a hint, the risk is not as high as you think.)

When we touched on COVID-19 and food safety, we examined what could happen if it was IN our food. Now, we are looking at it from a different point of view as it stands for groceries to come into our homes.

We’ll be looking into some of the research that touches on the main questions in this article. First, we’ll look at whether genetic material from the virus has been found on fomites. Then, we’ll examine whether the active form of the virus has been found on those surfaces. Last, we’ll look at what that means for COVID-19 and groceries, and what you should be doing to keep you and yours safe and healthy.

Genetic Material from the Virus

Although COVID-19 needs a human host to reproduce and spread, research has found that genetic material from the virus is detectable on various objects and surfaces outside of those hosts. One investigation found genetic material from the virus on floors and other surfaces in a hospital in Wuhan, China that had housed coronavirus patients. Half of the shoes that they tested came up positive. 75% of the computer mice from the ICU they tested had genetic material from the virus, as did 60% of trash cans and 40% of handrails. The air itself in the ICU yielded positive tests 35% of the time.

One important caveat to consider: the test looked for genetic material from the virus. There’s a difference between finding that genetic material and finding active viral particles themselves. It’s a bit like the difference between finding different parts of a car’s engine and finding a car that you can turn on and drive to the store.

It’s not just hospitals where genetic material from COVID-19 has been shown to hang around on fomites. The CDC recently published an investigation of the public health responses to COVID-19 on cruise ships. To quote from that study: “SARS-CoV-2 RNA was identified on a variety of surfaces in cabins of both symptomatic and asymptomatic infected passengers up to 17 days after cabins were vacated on the Diamond Princess but before disinfection procedures had been conducted …  Although these data cannot be used to determine whether transmission occurred from contaminated surfaces, further study of fomite transmission of SARS-CoV-2 aboard cruise ships is warranted.”

Viable Virus Particles

Another study published in the New England Journal of Medicine looked at how long COVID-19 can survive on different surfaces. This study was looking for the viable virus, not just the genetic material — to call on our example above, this is finding the working car, not just a bunch of car parts lying around.

The study found that the viable form of the virus could survive for four hours on copper, 24 hours on cardboard, and three days on plastic or on stainless steel. The study also looked at the half-life of the virus, which is the amount of time that it takes for the number of viable particles to be reduced by half. They found it to be .7 hours on copper, 3.5 hours on cardboard, 5.6 for steel, and 6.8 hours on plastic.

The authors of the study concluded that transmission of COVID-19 via fomites was theoretically plausible. That’s different than finding evidence that transmission occurs — it just establishes that it’s a possibility. A single viral particle isn’t enough to make someone sick; you need to be infected with the “minimum viable dose,” which is likely in the thousands or tens of thousands of particles.

Moreover, it’s important to remember that the chance that there’s enough of the virus on a given object to make someone sick depends on a lot of things: how much of the virus there was in the first place, the sort of object you’re talking about, how much moisture is in the air, how much sunlight there is, how much time has passed. All of these factors affect the chance that you become infected from an inanimate object.

The Washington Post caught up with Vincent J. Muster, one of the study’s authors and a scientist at the National Institute of Allergens and Infectious Diseases, to try and make sense of these different considerations. ““The risk of becoming infected via these routes of transmission reduces over time,” they quote Munster as saying. ‘That window of becoming infected is highest in the first 10 minutes, or one hour or two hours.”

Should You Wash Your Groceries?

To circle back around to our original question: do you need to disinfect your groceries to protect yourself from coronavirus? Not necessarily – but be cautious.

Healthline recently published an article talking to several scientists about that question. They got a range of responses. One of their sources emphasized that you’re much more likely to get the coronavirus from someone at the grocery store than you are from the groceries themselves. They recommend using a grocery delivery or curbside pickup service to stay safe.

Still, the World Health Organization says you can get the virus from touching something that’s contaminated and then touching your eyes or mouth. Another expert quoted in the Healthline article recommended common-sense measures to reduce that possibility: wash your hands after you get your groceries. If something comes in disposable packaging, throw the packaging out. And, if you feel compelled, wipe down cans and foods, or surfaces that you put your groceries on, prior to putting them away. Just use disinfectant instead of soap.

Other professionals, however, have said that you don’t need to sanitize your groceries. That was the upshot of a piece published by NPR. It emphasized that most of the transmission is, as stated above, person-to-person; fomite-to-person transmission isn’t yet a major driver of infection (or rather, the risk is very low). And, of course, touching an infected object isn’t enough on its own; you then need to touch your eyes or mouth without washing your hands properly. This is probably the most important takeaway: proper handwashing, not touching your face, and maintaining social distance are the most important things you can do to keep yourself safe.

By: Sean McNulty, Contributing Writer (Non-Lawyer)