The listeria outbreak in recent years has been associated with Miller's Organic Farm in Bird-In-Hand, Pennsylvania. The raw milk sold by the farm to people who were drinking unpasteurized milk, could have been the cause of infection. The cases of listeria infection have been reported since 2014. However, the cause was discovered only after when two patients got sick from the bacteria and one of them died.

Most recent outbreak of disease includes one case from California and another from Florida and the latter one died. The Pennsylvanian organic farm was held responsible for causing infection by The U.S. Centers for Disease Control and Prevention on Friday.

As per report, Miller's Organic Farm is still selling raw milk and is not aware of the health issues related to its production.

People have been advised by health officials to only drink pasteurized milk. There is possibility that unpasteurized dairy products may contain dangerous pathogens like listeria, salmonella, E. coli and campylobacter bacteria. During the pasteurizing process, many of the bacteria die due to high temperature.

No recall of the dairy products sold by the farm is announced yet, but health officials want consumer to be cautious of infection. “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”, the CDC said in a statement.

Last year, Blue Bell Creameries ice cream faced severe infection outbreak, killing three and causing illness to 10 people. In 2014, seven people died from listeria after consuming caramel apples.

According to CDC, listeria symptoms develop within a few days of eating contaminated food. These can be fever, muscle aches, headache, stiff neck, confusion, loss of balance, and convulsions. The infection can be fatal if bacteria intrude bloodstream or central nervous system.