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