Are Germs Hitchhiking in Your Child’s School Lunchbox?

As parents, we stock our kids’ lunchboxes with a variety of fresh fruits and vegetables, yogurt, hummus, salads, and other healthful foods. Then we ship them off to school, feeling confident that we’re offering them healthier food for lunch than the high-sodium, fat, and sugar meals of hot pockets, corn dogs, and meatloaf so common in school lunch programs. Yet it’s easy to forget that those healthful fresh foods are also great places for viruses and bacteria to thrive.

A combination of slips in cleanliness, lack of adequate food safety measures, and popularity of perishable items may create a breeding ground for bacteria. Most parents don’t do enough to keep kids’ foods cold enough, researchers from University of Austin found in a recent study. Findings published in the August 8 issue of the journal Pediatrics suggest that 90 percent of perishable foods in lunchboxes are not kept safely.

The researchers tested the temperature of perishable foods found in 705 preschoolers’ lunches an hour and a half before the children were scheduled to eat lunch. Only 1.9 percent of the lunches were at safe temperatures. The majority of the lunches – 88 percent – were at room temperature, even if Mom or Dad had remembered to throw in an ice pack that morning.

Even in childcare facilities that offered refrigeration, refrigerator temperatures were often higher than the USDA-recommended 40 degrees Fahrenheit or colder. Don’t forget to test the temperature in your own refrigerator. If it’s higher than 40 degrees, turn the thermostat down. Not only will your food be safer, it will last longer.

Still, keeping food cold is only one part of combating bacteria and viruses that may lurk in those lunchboxes – and lead to stomach upset and worse. Follow these ten tips to avoid those stomachaches and help reduce the risk of food poisoning.

Teach your child how to wash her hands. Hands should be washed and dried thoroughly before each meal. Most kids know that. But how many kids know how to wash those hands, including front, back, crevices, and all the other places that bacteria lurk? Don’t worry about using antibacterial soap – there’s no proof that they do any more good than plain soap, a lot of warm, running water, and a little elbow grease. Teach your kids the process, step by step: turn on the water, wet hands, soap hands and rub (including crevices) for at least 30 seconds, then towel off well. After hands are dry, grab an extra paper towel to turn off the faucets and turn the doorknob on the way out.

Clean before you pack: Before you begin assembling lunches, wash and dry your hands. Wipe down any countertops, cutting boards, or other surfaces that food will touch during preparation. Be sure that any kitchen sponges or dishcloths used to wipe down surfaces don’t harbor bacteria. Cutting boards are another favorite hide-out for bacteria, especially if they’ve developed deep cracks. The USDA Food Safety and Inspection Service recommends that consumers use separate cutting boards for produce and bread versus raw meat, poultry, and seafood. Wash cutting boards thoroughly in hot soapy water after each use. Disinfect them by flooding or immersing them in a solution of one tablespoon bleach to one gallon of clean water. Leave the board in contact with the bleach solution for several minutes, then rinse with clean water and allow to air dry. One minute in a microwave on the “high” setting will kill 99 percent of bacteria in your kitchen sponge.

When you pack lunch, pack lunch: Don’t try to multi-task – for example, doing laundry, tying kids’ shoes, or wiping snotty noses while packing lunches. Better yet, have your kids pack their own lunches the night before, while you supervise.

Pack fresh foods. Never pack food that’s past the expiration date, leftovers that have been around for more than a day or two, or food that looks or smells questionable.

Keep ‘em off the floor. Backpacks, purses, and even lunchboxes can easily end up on bathroom floors. And that’s not a good idea. There’s invisible fecal matter – the stuff my three-year-old calls “poopy” – on bathroom floors, especially public bathroom floors. Teach your child to hang backpacks on hooks or, better yet, keep them out of bathrooms altogether.

Keep hot foods hot and cold foods cold. At warmer temperatures, bacteria can thrive and multiply quickly. To keep food cold, use an insulated lunchbox and at least two icepacks, or purchase a container that can be frozen. Liquids should be kept in insulated jars to keep them hot or cold.

Thoroughly clean eating surfaces. Pack antibacterial wipes and teach your child to wipe down his eating area before he eats. If he eats at his desk, pack extra wipes and ask teachers to help. Desks are bacterial and viral magnets, well stocked in germs by the hands, papers, pens, pencils, books, and other things that land on them each day.

Wash backpacks and lunchboxes at least once a week. Most backpacks come with washing instructions. Follow them — frequently. Lunchboxes with non-porous surfaces should be wiped down daily with disinfecting wipes.

Encourage safe sharing: Teach your kids not to share juice drinks, chapsticks, drinks, or other goodies “mouth to mouth” with friends. If your child likes to share, pack a spare drink, and cut up fruits, sandwiches, and other items so she can share pieces – not bites of the whole apple. Or pack fruits like grapes that can more easily be shared.

Don’t be paranoid. Food is, after all, food. It’s meant to be eaten, enjoyed, and shared. In contrast, germs are everywhere. Good nutrition, adequate sleep, exercise, and other healthy lifestyle choices can go a long way toward combating food-related illnesses – and minimizing their effects when they do occur. So pack healthful foods, keep lunchboxes clean, and give your kids a chance to enjoy their lunches.

So the next time your child comes home from school with a troubled tummy, you might not want blame a virus. That stomachache, vomiting, and diarrhea might have been brought on by the foods you put in her lunchbox that morning. While insulated lunchboxes for kids have helped to improve food safety, bacteria can still thrive in them, causing food poisoning symptoms for your entire family.



Fawaz D. Almansour, F.D, Sweitzer, S.J., Magness, A.A., Calloway, E.E., McAllaster, M.R., Roberts-Gray, C.R., Hoelscher, D.M., &  Briley, M.E. (2011). Temperature of foods sent by parents of preschool-aged children.  Pediatric; peds.2010-2885; published ahead of print August 8, 2011, doi:10.1542/peds.2010-2885

United States Department of Agriculture, Food Safety and Inspection Service. (2010, December 8). Safe food handling: Basics for handling food safely. Available at:

United States Department of Agriculture, Food Safety and Inspection Service. (2010, December 8). Safe food handling: Cutting boards and food safety. Available at:


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