The listeria bacteria that killed two elderly men and affected two others, including a pregnant woman, has been linked to a dairy in Massachusetts, though health officials have not yet found the source of contamination within the dairy.
Whittier Farms Dairy, in West Sutton, remains closed until the source is found, according to Food Production Daily. Listeriosis, which can be deadly in those with weakened immune systems, affects 2500 people annually.