Reusable grocery bags could be a source of harmful bacteria. When going grocery shopping, do you use paper, plastic or reusable bags? Plastic bags have been banned in several places including San Francisco, Seattle and Los Angeles for environmental reasons, so the reusable bags are becoming a popular substitute. Many people are switching to reusable bags at the grocery store, but a scientific study shows that if you don’t wash your reusable bags, they could be carrying some dangerous bacteria. The 2011 study found that 51 percent of reusable bags that were tested had coliform bacteria on them. Washing the bags got rid of 99 point 9 percent of the bacteria, but the vast majority of people that participated in the study, 97 percent, said they don’t wash their reusable bags. A reusable bag was found to be the cause of an outbreak of norovirus on a girls’ soccer team travelling to a tournament. An investigation revealed the virus had been deposited on the bag after it was stored in the bathroom of one girl who had become ill. The teammates were eating snacks out of the bag, after it was stored in the bathroom of one girl who was feeling ill.