Last week, the Hy-Vee grocery chain temporarily banned reusable bags, saying it is difficult to monitor their cleanliness.
This week, Target began to ask customers to bag their own purchases if they're using their own bags. And many grocery stores are doing the same thing.
The governors of Massachusetts and New Hampshire have temporarily ordered the use of disposable bags in stores around their states, as a way to tamp down the spread of the coronavirus pandemic.
And the Minnesota Grocers Association has developed flyers for its stores to display at checkout lanes, saying reusable bags could be a carrier of the virus. The group cites a recent study that found the novel coronavirus can live on hard surfaces like plastic or stainless steel for up to 72 hours, and on cardboard for up to 24 hours.
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But the study did not specifically look at reusable bags — leaving shoppers with the question: What to do?
As it turns out: It depends on which researcher you talk to.
"I think, generally, the science doesn't support a need to ban the bags,” said Pete Raynor, an environmental health scientist at the University of Minnesota who studies airborne viruses.
He said viruses are less likely to survive for long periods of time on porous surfaces, like fabrics, than on hard surfaces.
"So if you're not making daily trips to the grocery store,” he said, “I think the science suggests that you're not going to have an infectious virus on the bag."
Raynor recommends shoppers wash their hands when they get home from the store — and he added that the COVID-19 outbreak has not changed his own family's shopping-bag habits.
"We're still using them, and I think it's the right decision,” he said. “I don't have any qualms about us taking groceries in reusable bags."
Experts agree that the main mode of transmission for the coronavirus is through the air, from someone nearby coughing or sneezing.
They say that touching an object that has the virus on it, and then touching your face, could be a secondary way the virus is spread.
So many won’t rule out the possibility that shoppers could pick up the virus from a reusable bag that’s touched a surface that has the virus on it.
A few years ago, researchers in California conducted a study in which they sprayed reusable bags with a kind of virus that doesn't infect people, before customers entered a grocery store. Then they followed shoppers through the store to see where the virus spread.
They found that the virus spread to shopping carts, and all over the checkout lanes — and to store employees’ hands.
"So there's the idea that you could bring [the virus] in [to the store], which is what we were testing,” said Ryan Sinclair, an environmental microbiology professor at Loma Linda University who led the study.
“But … as I've been thinking about this since the coronavirus, it's also about bringing things out of the store,” he said. “Even if you have a clean, reusable grocery bag, I think anything that you're touching on those surfaces in the grocery store can also bring things out."
Sinclair said he supports broader efforts to encourage the use of reusable bags, including California’s law that bans the use of single-use plastic bags. But he said right now, he feels it's safer for his family to use disposable ones.
Most experts, though, say reusable bags are not going to be a major vehicle of spread for the coronavirus.
"You’re going to see these types of reactions all over the country with specific household items that concern is raised over,” said Amesh Adalja, an infectious disease and critical care physician at the Johns Hopkins Center for Health Security.
“However, in the grand scheme of things, I don’t think it’s something that people should spend much time worrying about,” he said. “If you want to use a reusable bag, it's fine."
Adalja said people can become overwhelmed if they start worrying about all the items that could potentially be vehicles for transmitting the virus. Instead, he said, people should focus on the basic advice public health officials everywhere have been stressing: "Social distancing, washing your hands, not touching your face, trying to avoid sick people if you can, and if you are sick, staying home so you don’t contaminate others," he said.
But there are steps shoppers can take to make sure their reusable bags are not contaminated.
Joseph Vinetz, a professor of infectious diseases at the Yale School of Medicine, said it's not a bad idea to spray reusable bags with an alcohol-based cleaning solution. Or wash them with soap and water. If they’re cloth bags, run them through the washing machine.
And, if governments or stores want to ban reusable bags, Vinetz said, that's OK, as long as it’s for a short period of time.
“I think that using billions of plastic bags a year is a bad thing for our environment,” he said. “But right now, it’s even worse for our environment to have an ongoing pandemic.”
Health officials for weeks have been increasingly raising the alarm over the spread of the novel coronavirus in the United States. The disease is transmitted through respiratory droplets, coughs and sneezes, similar to the way the flu can spread.
Government and medical leaders are urging people to wash their hands frequently and well, refrain from touching their faces, cover their coughs, disinfect surfaces and avoid large crowds, all in an effort to curb the virus’ rapid spread.
The state of Minnesota has temporarily closed schools, while administrators work to determine next steps, and is requiring a temporary closure of all in-person dining at restaurants, bars and coffee shops, as well as theaters, gyms, yoga studios and other spaces in which people congregate in close proximity.