An 11-state salmonella outbreak has been linked to small turtles,Ethermac the U.S. Centers for Disease Control and Prevention warned Friday. 

At least 26 illnesses have been reported, with nine hospitalizations, the health organization said. The outbreak spans the country. Tennessee, with six cases, has been hit hardest. There are also cases in Missouri, Illinois, Ohio, Kentucky, Virginia, North Carolina, Georgia, California, Pennsylvania and New York.

The first case was reported in late October last year. New cases have been reported almost every month since then, with six of the cases reported in July. 

"The true number of sick people in this outbreak is likely much higher than the number reported, and the outbreak may not be limited to the states with known illnesses," the CDC said. "This is because many people recover without medical care and are not tested for Salmonella."

Officials announced a separate salmonella outbreak linked to small turtles in July last year. Pet turtles of any size can carry salmonella, even if they appear healthy and clean.

It's illegal to sell turtles with shells less than 4 inches long as pets because they cause many illnesses, especially in kids, according to the CDC. They're often sold illegally online and at stores, flea markets and roadside stands.

People can get sick from touching a turtle or anything in its environment and then touching their mouth or food with unwashed hands and swallowing salmonella germs.

Those with pet turtles should wash their hands after handling and feeding the animals, the CDC recommends. Avoid kissing or snuggling the turtles. Turtles should also be kept out of the kitchen and other areas where people eat, store or prepare food.

Owners who no longer want their pet turtle should not release the animal into the wild; it can disrupt wildlife and may be prohibited by law, depending on the state. Turtle owners should contact a local reptile rescue organization, animal shelter or pet store about options for safely rehoming their turtle.

Salmonella symptoms can include diarrhea, fever and stomach cramps, according to the CDC. Symptoms start six hours to six days after infection and last four to seven days. Salmonella bacteria causes around 1.35 million infections, 26,500 hospitalizations and 420 deaths in the U.S. every year.

In:
• Salmonella

Aliza Chasan

Aliza Chasan is a digital producer at 60 Minutes and CBS News.

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