WSJournal. Can Insects Come in the Mail?

Everything from car seats to cat food can now be delivered to our doorsteps. But in addition to the item you ordered, what else may be lurking inside the packing box? Shripat Kamble, former director of the certification program for the Entomological Society of America and a professor of Entomology at the University of Nebraska, Lincoln, scratches the issue.

Shipping Stowaways

Bugs gravitate to cozy homes as much as the rest of us—especially for laying their eggs—which makes a packing box an especially inviting place to hide. Cartons shipped from warehouses in warm, moist climates, where critters tend to thrive, may be particularly susceptible to an insect invasion.

A bug in a box can be a hardy traveler. Cardboard is a good insulator for small critters, even if it is cold outside, says Dr. Kamble. "Climate doesn't have a whole lot to do with survival, since the inside temperature doesn't get that cold." And a lack of food isn't an issue either. "We have known bedbugs to survive 30 to 40 days with no food," he says.

For the most part, says Dr. Kamble, the creatures you may find in the foam peanuts—besides mice—are live adult specimens and egg cases of common insects like roaches, moths, beetles, spiders and bedbugs. But the list, he says, goes on and on.

Tolerance for creepy crawlies on the receiving end varies, says Dr. Kamble. In warm-weather climates, where people see bugs all the time, they may not be too bothered by a few ants or roaches. "But if you go way up North, where you rarely find any insects, you'll find people's tolerance is very low," he says.

Keeping Out the Crawlers

The U.S. Department of Agriculture inspects containers coming in from other countries to our ports. Still, what the USDA actually opens amounts to a fraction of the total, says Dr. Kamble.

Many vendors spray warehouses regularly with pesticides to avoid infestation, though some don't bother if the bugs aren't a nuisance to them. Unfortunately, unlike the occasional moving company that sometimes offers to spray individual boxes for clients, consumers rarely have a say in the matter in retail deliveries.

To keep six- and eight-legged creatures from surreptitiously moving onto your turf, Dr. Kamble suggests following a few rules. First, don't order exotic plants from tropical places, where insects like to burrow. "Once they arrive into your home, the temperature is nice, you have ready-made food in your kitchen, and the insects are ready to go," says Dr. Kamble. "They want to share your life."

Other pointers: Open delivery boxes in a garage or outside. If you live in an apartment, keep the box isolated in a small room. Look for seed-like droppings, immature stages of insects (such as larvae), egg sacks (which can resemble small bean bags) and anything moving.

"But just because we don't see them, doesn't mean they're not present," says Dr. Kamble, emphasizing that tiny bugs can live in the folds or even the corrugation of boxes.

For extra precaution, spray any suspect imports with an aerosol pesticide, or stick the box in the freezer for a couple of days. "That will kill anything," he says.

Once your boxes are unpacked and broken down, remove them from your home. Should you need to store your recent purchase, do so in plastic. "Cardboard is warm and cozy for bugs, with lots of hiding spots," says Dr. Kamble. "But there is no refuge in a plastic box."

Bedbugs From Abroad

Among the most insidious of today's traveling pests, says Dr. Kamble, are bedbugs. After being a big problem in the 1940s and 1970s, "they seemed to go away," he says. But with so much travel and movement over the past 10 years, "now we see them everywhere."

While you are more likely to find an infestation in secondhand fabric that has been passed between more people, it isn't unheard of for bedbugs to have burrowed into new fabric or clothing—especially if it originates from factories in tropical locales where tolerance for creepy crawlies may be higher.

As for this Nebraska-based entomologist, he won't be ordering his produce or plants by mail any time soon, for fear of alarming his family with unwanted pests. "I don't dare order food online," says Dr Kamble. "My wife is from North Dakota, where they have a low tolerance for bugs. She would kill me if she saw even one."