Salmonella, Campylobacter, and E. coli in dairy farms: current trends and implications for raw milk consumption.

Resumen

In 1938 raw milk was responsible for 25% of all food-borne diseases. The city of Chicago passed the first compulsory pasteurization law in 1908. Between 1973 and 1992 there were 2.4 milk-borne outbreaks due to raw milk consumption per year while between 1993 and 2006 they doubled (5.2). One of the most recent outbreaks occurred in Pennsylvania in 2012 with more than 71 cases of Campylobacter confirmed in four states. Ironically the milk came from the farm “The Family Cow” and was sold by the store “Healthy Grocer”. Campylobacter is a common inhabitant of the intestine of the cow and other animals. The U.S. Animal Health Monitoring System has determined that 92.6% of the dairy farms and 33.7% of the cows are positive to this microorganism. Dairy producers who were unaware of the presence of pathogenic bacteria in their milk were twice as likely to drink it raw; the two main factors cited were flavor (72%) and convenience (60%). Health regulations and sanitary rulings have protected consumers from diseases transmitted by the consumption of unpasteurized milk or dairy products. This has created a partnership of trust between producers, industry, and consumers that once broken it will require a long time to reestablish. In the U.S. the population at risk is approximately 3.5%. In Latin America it is more than likely higher because of the greater consumption of home-made fresh cheese made with unpasteurized milk. This study will address the bacteriological status of raw milk in the U.S. with special emphasis on Salmonella, E. coli, and Campylobacter and its implications for raw milk and unpasteurized dairy products.