While of course, everyone worries about rabies, but this would be an extremely low risk. Rabies virus is an enveloped virus and does not survive in the environment well if at all. While there have been some rare, laboratory-created instances of it be transmitted through aerosol with depleted oxygen, this is really a non-factor. The bigger risks are the normal foodborne pathogens that can be carried by bats, including Campylobacter, Listeria, Salmonella, Shigella, and Yersinia as well as some more exotic bacterial types. Depending on where the bat entered the system would determine the amount of dissemination of these types of organisms.
Now how does bat get into a bag? If not intentionally placed there by someone, and one had to guess....it would most likely come into the packaging area of the processing plant at night. The greens are chopped and washed, so unlikely that it came in the loads of produce (unless some component was not chopped). More likely, this flew into the plant at night when doors were left opened and took refuge in the equipment. If this were the case, it occurred after sanitation. When the greens started flowing, the little dude was crushed and loaded into the bag. All a guess of course, but if true, would probably be in one of the bags from early in the production run.. Prevention....keeping doors shut at night, especially dock doors. X-ray equipment would have likely found this if in place.
FDA Recall Notice
https://www.fda.gov/Safety/Recalls/ucm551649.htm
Precautionary Recall of a Limited Quantity of Organic Marketside Spring Mix Salad is Announced by Fresh Express
For Immediate Release
April 8, 2017
https://www.fda.gov/Safety/Recalls/ucm551649.htm
Precautionary Recall of a Limited Quantity of Organic Marketside Spring Mix Salad is Announced by Fresh Express
For Immediate Release
April 8, 2017
