A study conducted by CDC evaluated the outbreaks associated with organic foods. From the study: "We identified 18 outbreaks caused by organic foods from 1992 to 2014, resulting in 779 illnesses, 258 hospitalizations, and 3 deaths". Salmonella and pathogenic E.coli were the leading causes. There were a range of foods involved: "Eight of the outbreaks were attributed to produce items, four to unpasteurized dairy products, two to eggs, two to nut and seed products, and two to multiingredient foods."
As stated in this study, it is hard to calculate risk of organic foods compared to conventional foods. However, we can say that just because it is organic, it doesn't mean that you still don't need proper handling and preparation.
It is also important to point out that over the period of time covered in this study, the capabilities for identifying outbreaks and tracking to the source have improved greatly. So looking at the number of outbreaks occurring from year to year can be misleading.
Journal of Food Protection, November 2016
Foodborne Disease Outbreaks Associated with Organic Foods in the United States
Consumer demand for organically produced foods is increasing in the United States as well as globally. Consumer perception often credits organic foods as being safer than conventionally produced foods, although organic standards do not directly address safety issues such as microbial or chemical hazards. We reviewed outbreaks reported to the Centers for Disease Control and Prevention's Foodborne Disease Outbreak Surveillance System where the implicated food was reported to be organic. Information collected for each outbreak included the year, state, number of illnesses, pathogen, and implicated food. We identified 18 outbreaks caused by organic foods from 1992 to 2014, resulting in 779 illnesses, 258 hospitalizations, and 3 deaths; 56% of outbreaks occurred from 2010 to 2014. Nine outbreaks occurred in a single state, and nine outbreaks were multistate. Salmonella sp. (44% of outbreaks) and Escherichia coli O157:H7 (33%) were the most commonly occurring pathogens. Eight of the outbreaks were attributed to produce items, four to unpasteurized dairy products, two to eggs, two to nut and seed products, and two to multiingredient foods. Fifteen (83%) outbreaks were associated with foods that were definitely or likely U. S. Department of Agriculture certified. More foodborne outbreaks associated with organic foods in the United States have been reported in recent years, in parallel with increases in organic food production and consumption. We are unable to assess risk of outbreaks due to organic foods compared with conventional foods because foodborne outbreak surveillance does not systematically collect food production method. Food safety requires focused attention by consumers, regardless of whether foods are produced organically or conventionally. Consumers should be aware of the risk of milk and produce consumed raw, including organic.