What common food source is associated with Norovirus outbreaks?

Raw and insufficiently prepared shellfish are commonly associated with Norovirus outbreaks due to their ability to accumulate and harbor the virus when they filter contaminated water. Shellfish, particularly bivalves such as oysters, clams, and mussels, can become contaminated with Norovirus when they are harvested from waters that are polluted with fecal matter containing the virus. If these shellfish are not cooked properly, the heat may not be sufficient to eliminate the virus, thus leading to foodborne illness when consumed.

While raw vegetables, undercooked seafood, and contaminated water can also be associated with various foodborne illnesses, the specific and strong association of Norovirus outbreaks with raw and undercooked shellfish is well documented. This highlights the importance of thorough cooking and proper handling of shellfish to prevent the transmission of Norovirus.