The US Food and Drug Administration (FDA) said testing of the milk, produced by Miller's Organic Farm in Bird-In-Hand, Pennsylvania, showed it was closely related genetically to Listeria bacteria from two ill people.
Both people, aged 73 to 81 years were hospitalized, and the ill person in Florida died.
Listeria finding allows traceback
The Centers for Disease Control and Prevention (CDC) said although the two illnesses were in 2014, the source wasn't known until late January this year when the FDA informed it of WGS testing.
“Because Listeria was recently found in raw milk produced by Miller's Organic Farm, CDC is concerned that conditions may exist at the farm that may cause further contamination of raw milk and raw dairy products distributed by this company and make people sick,” said the agency.
“We recommend that people drink and eat only pasteurized dairy products (including soft cheese, ice cream, and yogurt).”
Raw milk is from cows or other animals that has not been pasteurized to kill harmful bacteria.
Samples of raw chocolate milk were collected in November 2015 from a raw milk conference in Anaheim, California and Listeria was isolated from it.
CDC said once illnesses were identified public health officials interviewed them or family members about what they may have eaten and other exposures in the month before illness.
“Interviews were conducted with the ill person from California and family members for both ill people. It was reported that both ill people drank raw milk before they got sick. The family of the deceased person in Florida reported purchasing raw milk from Miller's Organic Farm.”
Californian cheese warning
Meanwhile, the California Department of Public Health (CDPH) has warned the public about illegally manufactured Mexican-style soft cheeses, often sold by street vendors.
Dr Karen Smith, director and state public health officer, said: “These cheeses are often made with raw, unpasteurized milk and under unsanitary conditions. We are seeing a dramatic increase in the number of reported Salmonella cases, particularly in the Hispanic community.”
Since November 2015, at least 50 patients have been infected with three different strains of Salmonella. No deaths have been reported but several cases have been hospitalized.
The investigation is ongoing, but several patients reported eating potentially unpasteurized Mexican-style cheese from street vendors before they became ill.
The California Department of Food and Agriculture (CDFA) recommends purchasing cheeses made by licensed manufacturers and kept in refrigerated cases at retail stores.