Click here for a report by Oregon public health officials entitled: “A Point-Source Norovirus Outbreak Caused by Exposure to Fomites.”

Nine members of a soccer team in Oregon, girls aged 13-14 and adults, became sick from touching a polypropylene reusable bag or consuming its packaged food contents. Seven experienced vomiting, four had diarrhea. Symptoms ranged from one to seven days. The officials also identified at least five presumptive secondary infections among household members.

All of the people who became ill consumed cookies that were in sealed packages. The packaged cookies were stored in a polypropylene reusable bag. Not all of the people who became ill touched the reusable bag, but they all touched the packaging of the cookies which had been in contact with the inside of the bag.

All three stool specimens collected from ill persons were positive for norovirus genotype GII.2. Viral sequences from the three stool specimens were identical and a 98% match to a GII.2 reference sequence. Two of ten swabs taken from the reusable bag were still positive for the same norovirus genotype two weeks later. The report concludes: 

The data indicate that virus aerosolized within the hotel bathroom settled upon the grocery bag and its contents, and it was touching the bag and consumption of its contents that led to the outbreak. Touching the bag could not be analyzed separately from consumption of food items from within the bag. Consumption of food from the grocery bag was strongly associated with illness, as was handling the grocery bag. The nature of the contaminated foods—a bag of chips, grapes, and a package of cookies—facilitated transmission. Fingers contaminated with norovirus have been shown to sequentially transfer virus to up to 7 clean surfaces, and environmental contamination with transmission via fomites has been documented. Incidentally, this also illustrates one of the less obvious hazards of reusable grocery bags.

Two points must be emphasized:

The fact that the cookies were in sealed packages did not protect against transmission of the virus. In fact, it was the sealed packaging (which had been in contact with the inside of the reusable bag) that served as a vehicle for transmission.

The fact that a reusable bag can harbor an infectious virus for two weeks or more is a serious concern.