The U.S. Centers for disease Control reports that raw milk produced by Miller’s Organic Farm in Bird-In-Hand, Pennsylvania, is the likely source of this outbreak.

Two people infected with the outbreak strain of Listeria were reported from California (1) and Florida (1). Both illnesses occurred in 2014.

Both people were hospitalized, and the ill person in Florida died as a result of listeriosis.

Although the two illnesses occurred in 2014, the source of these illnesses wasn’t known until January 29, 2016, when the U.S. Food and Drug Administration informed CDC that whole genome sequencing of Listeria bacteria from raw chocolate milk produced by Miller’s Organic Farm showed that it was closely related genetically to Listeria bacteria from the two ill people described above.

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.

In November 2015, samples of raw chocolate milk were collected from a raw milk conference held in Anaheim, California. The raw chocolate milk was produced by Miller’s Organic Farm. The U.S. Food and Drug Administration (FDA) isolated Listeria from the raw chocolate milk and conducted WGS testing on the isolate to get more genetic information about the bacteria. On January 29, 2016, FDA informed CDC that WGS determined that the Listeria bacteria from the raw chocolate milk was closely related genetically to Listeria bacteria from two people in two states who got sick in 2014, one from California and one from Florida.