TAMPA, Fla. (WFLA) — The Food and Drug Administration issued a safety advisory to restaurants and retailers in six states, warning that a recent batch of oysters may be contaminated.

In an advisory issued Oct. 20, the FDA said its Canadian counterpart, the Canadian Food Inspection Agency (CFIA), tested oysters harvested by Future Seafoods, Inc. and found salmonella and E. coli.

The oysters were harvested on Oct. 10 and were sold to establishments in Florida, Massachusetts, Maryland, Maine, Pennsylvania and Virginia. Future Seafoods, Inc. has not issued a recall, but restaurants are advised to dispose of the oysters, and consumers are urged not to eat them.

“The FDA is awaiting further information on distribution of the oysters harvested and will continue to monitor the investigation and provide assistance to state authorities as needed,” the FDA safety advisory stated.

The CFIA is looking into what caused the oysters to become contaminated.

Symptoms of salmonella infection

Food contaminated with salmonella and E. coli may look and taste normal, but the FDA warns it can cause serious illness, especially in those with weakened immune systems.

In most people infected with salmonella, symptoms begin to appear in about 12 to 72 hours. The resulting illness, known as salmonellosis, causes diarrhea, fever and abdominal cramps. In severe cases, people can develop high fever, aches, headaches, lethargy, a rash or blood in the urine or stool, which requires medical attention.  

Salmonellosis usually lasts four to seven days, and most people recover without treatment, according to the FDA.

Symptoms of E. coli infection

E. coli and salmonella infection produce similar symptoms, according to the FDA, but some types of E. coli bacteria can also cause a life-threatening infection.

After eating contaminated food, symptoms could appear anywhere from a few days to as many as nine days later. Generally, those infected with E. coli experience severe stomach cramps, diarrhea, fever, nausea and vomiting.

According to the FDA, severe infections can cause bloody diarrhea and life-threatening conditions, such as kidney failure or the development of high blood pressure, chronic kidney disease and neurologic problems. Other infections may cause no symptoms or may resolve without treatment in five to seven days. 

Because symptoms range from nausea to life-threatening illness, the FDA urges anyone who suspects they may have been infected with E. coli to talk to their doctor. Children under the age of 5, adults older than 65, and people with weakened immune systems are more susceptible to severe illness.

Anyone who believes they got sick after eating contaminated food at a restaurant is asked to file a complaint with the FDA and report the illness as an adverse event.