Editor's note: Interviews for this story were conducted in March 2020, and, unless otherwise specified, most sources cited were published in the past month. Please keep in mind that our understanding of coronavirus is constantly changing. And see our earlier piece on the safety of delivery and takeout food during the pandemic.
The virus that causes COVID-19 is known to transmit from person to person, with no evidence thus far of spread via food or food packaging. Still, to reduce your risk, health authorities urge frequent hand washing and care around potentially contaminated surfaces. Suddenly grocery shopping feels like a brush with death.
So what does the pandemic mean for your cereal box or your avocados? How can you minimize risk while obtaining the fresh food you need to keep your family healthy? Here’s what I’ve found after consulting with scientists, and reviewing articles, research and expert guidance.
BEFORE YOU HIT THE STORE
More than anything, contact with other people increases your risk. Here’s how Rutgers University food microbiologist Don Schaffner put it:
“Mostly I’m worried about what’s going to happen to me 5 to 14 days after I went to the grocery store,” he said. “It’s not the milk carton. It’s that person I was standing next to that wouldn’t move out of the way when I went to grab the milk. That’s where my risk was.”
So, is there another way you could get your groceries? Delivery, perhaps? Is your store offering a no-contact pick up? In my area (Washington, D.C.), some restaurants are delivering “pantry staples” and farmers and producers are bringing dairy, eggs, vegetables, and even pickles directly to people’s doors.
Short of delivery, can you go at a less crowded time, visit a smaller store or strategize to minimize your time shopping? Wherever or whenever you go, make sure to wear a mask and keep six feet between you and other people at all times.
AT THE STORE
Groceries generally are not high-touch surfaces
It’s mostly high-touch surfaces that concern experts, like the handle of the grocery cart or the screen at self-checkout. Multiple sick people could have deposited virus on them or a single sick person could have touched them many times, increasing the amount of potential virus. If the store provides wipes, use them. Otherwise, bring your own, advises Ben Chapman, a food safety specialist at North Carolina State University.
Individual grocery items haven’t been handled as much, so their odds of carrying the virus are lower. Keep them that way and don't touch items you don’t plan to purchase. Chapman also suggests using hand sanitizer as you enter and exit the store and keeping your distance from people.
And, of course, in a crowded store it’s critical to avoid touching your face.
Virus viability on packaging
Let’s say your jug of olive oil was handled by an infected person who managed to cough virus all over it.
A recent study in The New England Journal of Medicine found that, at room temperature, the novel coronavirus survived for up to three days on plastic (same for steel; cardboard was 24 hours; copper just four hours), though even within those three days the amount of viable virus steadily decreased. So, the risk starts out low, and decreases as time passes. (Of course, this is just one study and future studies could find differently. Chapman noted: “We’re not going to have a complete picture of this a year from now, so we can’t expect to have a complete picture of it today.”)
So, per the study's findings, someone would have needed to contaminate the olive oil bottle fewer than three days ago for it to pose a risk. OK. What if it was sneezed on this morning? Could it somehow make you sick?
While the transference rates of the novel coronavirus haven’t been directly studied, Schaffner said the rule of thumb is less than 1 percent transfer between dry surfaces. So, if your dry hand touches the dry exterior of the contaminated bottle, you’d probably pick up less than 1 percent of the virus. To become infected, you’d then need to touch your face where you’d again deposit less than 1 percent of what was on your hand. If any of the surfaces were wet, however, more virus could transfer.
Schaffner also notes that the virus can live longer at cold temperatures, so, in the off chance there was virus on a refrigerated product, it’s more likely to stick around. But, again, while much remains to be learned, as of this writing in late March 2020, experts say not a single case of COVID-19 has been traced back to someone handling contaminated food packaging.
What about selecting produce?
The recent study of survival times on surfaces didn’t address produce, but keep in mind that COVID-19 is a respiratory infection with no evidence thus far of transmission via food (and if you're wondering about it getting into your mouth via contaminated food, Schaffner notes that's theoretically possible, but "we have no evidence that this happens with any regularity in the real world."). Once you swallow it, Matt Moore, a food and environmental virologist at the University of Massachusetts-Amherst, said your stomach, bile and digestive enzymes will probably destroy it.
Scott Monroe, a Purdue Extension food safety educator said in a press release: “While viruses may be transmitted from surfaces, most growers take steps to prevent contamination. At this point in time, fear of COVID-19 should not be a reason to stop purchasing fresh fruits and vegetables.”
As an additional precaution, this fact sheet from North Carolina State University, suggests using hand sanitizer before and after selecting produce.
Are reusable bags OK?
Coronavirus fears have prompted reusable bags bans and advice to ditch them has been circulating on social media, but Chapman's team at North Carolina State reports: “At this time, there is no link between reusable bags and COVID-19. Reusable bags are not considered a significant risk factor in the spread of COVID-19 and as such do not need to be banned from stores.”
They recommend cleaning the bags after each use as a good practice, both during a pandemic and otherwise.
WHEN YOU GET HOME
Wash your hands!
First, wash your hands. They are more likely than any of your groceries to have viable amounts of virus on them.
Should you deep clean your produce?
Despite some well-meaning tips floating around online, food safety experts advise against washing produce in soap and water or misting it with a bleach solution. Schaffner said the risk of getting coronavirus from food is so low that it doesn’t justify the risk of ingesting soap or bleach.
“You’re managing what we believe to be an infinitesimally small risk by doing something that we know is a greater than infinitesimally small risk,” he said, reiterating that no cases of coronavirus have been traced to food. “We know people have gotten sick from soap,” he said. “We know people have gotten sick from bleach."
Especially in a moment when hospitals are filling with people suffering from COVID-19, the last thing you want to do is land yourself in the emergency room because your salad was dressed with bleach.
But, aren’t we being told to clean our counters with a bleach solution? Don’t we tolerate soap residue on our dishes?
“You’re not eating the dish,” Schaffner said. He also noted that products like dish soap and hand soap tend to come with warnings about ingestion leading to nausea, vomiting and diarrhea.
As for handling produce, food safety experts advise washing it thoroughly with water, like usual, and washing your hands regularly before, during and after preparing food. If you’re considering a product marketed as a veggie wash, Schaffner notes that none of them has been tested against the novel coronavirus virus, and these products are likely no more helpful than water. He said research has also shown that vinegar is not much better than water in cleaning produce.
What about nonperishable goods? Should you wipe them down?
It’s easy to find folks online urging you to wipe down your packaged groceries with Lysol, bleach solutions and other disinfectants. Schaffner noted that during times of uncertainty, such actions can give people a sense of security. If it makes you feel better, go ahead, he said. But it’s not something he’s doing.
“The problem is we’re talking about managing risk and we really don’t have good information about what constitutes that risk and we’re managing theoretical risk on top of theoretical risk,” he said. “Eventually it just becomes kind of crazy making.”
Chapman said he reserves disinfection products for the scenarios he feels are the greatest risk, like high-contact surfaces at the grocery store or a doctor’s office. For him, grocery items don’t merit the alcohol, wipes, etc. that are tough to find these days.
“The virus is not going to jump off that package. It’s really only going to move because of my hands. So why not control my hands?” he said. “I really don’t want to be wasting sanitizer and wipes. I really want to make sure I focus on what can I do. And for me, that’s washing my hands.”
What about products that need to be kept cold?
Refrigerate or freeze them right away! It’s theoretically possible that any virus lingering on them could remain viable for longer in your fridge. Again though, there's no evidence of the virus being transmitted via food packaging. But, if you’re concerned, you can use disinfection products on them. And, of course, wash your hands before you sit down to eat.
How one food safety expert handles groceries
I asked Chapman, who has spent the past couple weeks working on a series of fact sheets on many angles of food safety amid coronavirus (check them out here), what his grocery shopping looks like these days.
He said he plots his trips carefully, trying not to go too often. On arriving, he immediately wipes down or sprays sanitizer on his grocery cart. Then, he shops as normal, getting fresh produce and his other usual products. He avoids cashiers, and wipes down the self-checkout screen before using it. He applies hand sanitizer just after leaving the store.
At home, the first thing he does is wash his hands. Then, he unloads his reusable bags onto his counter and drops the bags directly into his washing machine. He puts his groceries away, washes his hands and then cleans and sanitizes his countertops.
He also washes his hands frequently while preparing meals and before eating, but these are practices he said are standard—not just a good idea in the midst of a pandemic.
What I decided to do
We are avoiding the store and relying on our stash of fresh, long-lasting fruits and vegetables. Moving forward, we're hoping to get groceries delivered.
Once groceries do arrive, given the study finding that the virus could remain viable on surfaces for three days, I set aside shelf-stable items for a couple days. I also give a quick 62 percent alcohol wipe down on the “touchy” parts of packaged goods that we immediately put into our fridge or freezer (it’s actually a drinking alcohol, just above the threshold for effectiveness; we’re saving our more potent supplies for if one of us gets sick or we need to go to a public place). My extra steps aren’t things that the scientists I spoke to are doing, but they do make me feel better. I shared my approach with Chapman.
“We don’t have a lot of control in this outbreak and that’s one thing you can do to that gives you some control,” he said. “It’s not going to hurt. It might not do anything.” And he repeated his emphasis on hand washing as the best thing you can do.
To be sure, we are washing our hands frequently, especially at various points when preparing food and before eating. This helps further reduce our risk, while also giving us extra protection from other foodborne pathogens (now would be an especially bad time to wind up hospitalized with a horrific gastrointestinal problem). Though, just in case we might forget to wash our hands, my extra steps give me a touch more peace of mind, even if it's more psychological than science-based. As mentioned several times above, there is not yet any evidence of the virus spreading via food or food packaging.
Stay safe and healthy out there!
So, please be safe out there. Eat well, and put your energy into staying away from other people and washing your hands and not obsessing over the theoretical risk of every grocery item that comes into your home. Final word goes to Moore, the virologist:
"I think people are focusing a little too much on foods when it really should just be high touch surfaces, making sure you're washing hands and not touching your face and really trying to avoid contact with other people because that’s the really the primary way this can be spread."
COVID-19 Food Safety Resources - North Carolina State University
Food Safety and Coronavirus: A Comprehensive Guide: Serious Eats
The Coronavirus (COVID-19): Food Safety Recommendations & Frequently Asked Questions for the Consumer - Institute for Food Safety At Cornell University