The Centers for Disease Control and Prevention announced Wednesday that its investigation of a multi-state outbreak of listeria linked to Blue Bell Creameries is complete, but warned that some customers may still be at risk.

"This outbreak investigation is over," CDC officials said in a press release. "However, people could continue to get sick because recalled products may still be in people’s freezers and consumers unaware of the recalls could eat them. Institutions should not serve and retailers should not sell recalled products."

Blue Bell Creameries issued a statement as well, and said they have given the Food and Drug Administration a detailed list of corrective actions they are taking in response to inspection reports from the company's facilities in Brenham, TX, Broken Arrow, OK, and Sylacauga, AL.

"The company is currently in the process of comprehensively reviewing all aspects of operations at the three facilities," the statement reads. "Because listeria is ubiquitous in the environment, the company has adopted a broadly focused remediation plan aimed at confronting any possible sources of contamination."

"This process has led Blue Bell to “reassess everything” about its operations and identify a number of enhancements that will be made, including updated environmental and product testing procedures."

Blue Bell CEO and President Paul Kruse said the company will resume production as soon as revised operating methods at its creameries are in place and facilities demonstrate that they are capable of ensuring product safety.

Blue Bell voluntarily recalled some products in March after samples tested positive for Listeria monocytogenes. Those products were served in hospitals where fatal listeria cases were reported. On April 20, Blue Bell recalled  all of its products after a samples of its half gallon Chocolate Chip Cookie Dough products also tested positive for the bacteria.

In May, Blue Bell announced that it had agreed to strict new testing and production procedures, including a "test and hold" policy for all products.