The bat was sent to the CDC after it was found in a bag of Fresh Express Organic Marketside Spring Mix.
"The deteriorated condition of the bat did not allow for CDC to definitively rule out whether this bat had rabies," the Atlanta-based agency said
The CDC said the risk of rabies transmission was extremely low but not zero, so the two people who ate salad mix were recommended for treatment as a precaution.
They are fine and show no signs of having rabies, the CDC said.
Fresh Express has recalled packages of the salad mix
that were sold at Walmarts in Alabama, Florida, Georgia, Louisiana, Mississippi, North Carolina, South Carolina, and Virginia.
The affected product has the production code G089B19 and best-if-used-by date of Apr 14, 2017 on the front label, and UPC code 6 8113132897 5 on the bottom of the container.
"Upon receiving notification, both Walmart and Fresh Express food safety and rapid response teams, in close coordination with regulatory authorities, acted immediately to review all relevant records, launch an intensive investigation and initiate product removal and recall procedures," Fresh Express said.
There have been no other reports of animal matter.
The Florida Department of Health, US Food and Drug Administration and CDC are part of the investigation into the dead bat.