Mass. dairy that produced milk tainted with deadly bacteria cooperating with authorities

The pasteurization process at a central Massachusetts dairy connected to a deadly outbreak of a bacterial illness appears to be working properly, a state health official said Friday.

Dr. Alfred DeMaria, the state director of communicable disease control, said that could mean the listeria bacteria that sickened four people in Massachusetts entered Whittier Farms' milk supply after it was pasteurized. Two of those victims, a 78-year-old man and a 75-year-old man, died in June and October. Another elderly man and a pregnant woman survived, although the woman miscarried.

"My understanding is they did everything right," DeMaria said. "That could happen. You could do everything right and something bad could happen."

The Shrewsbury dairy has suspended operations and is cooperating with state officials trying to pinpoint the source of contamination, DeMaria said. The farm delivered milk mostly to homes in the Worcester area.

"We are a family owned and operated business with a reputation for providing farm fresh milk to our customers," Whittier Farms said in a statement. "We strive to produce the best product and therefore we are extremely concerned about the situation and will be working to obtain the results of the investigation."

A message left for further comment was not immediately returned Friday.

DeMaria said the Massachusetts outbreak is believed to be just the third ever in pasteurized milk in the United States. Listeria is more commonly associated with luncheon meats, soft cheeses and hot dogs. It also can be found in raw, or unpasteurized, milk, he said.

An elderly man sickened asked health officials about the milk in his refrigerator, and an unopened container from Whittier Farms later tested positive for listeria. Testing showed the bacteria that sickened all four people likely came from the same source.

The bacteria can cause listeriosis, a rare but potentially fatal disease that can kill babies and people with weakened immune systems and cause miscarriages in pregnant women. Symptoms include fever, headache, stiffness, nausea, abdominal pain and diarrhea.