Dec 24, 2015 05:12 AM EST By Rashmi Kalia, UniversityHerald Reporter

A U.S. study suggests that tiny turtles may be responsible for a growing number of salmonellosis outbreaks in the country, Reuters reports.

"All turtles - healthy and sick, big and small - can carry Salmonella," said lead author Dr. Maroya Walters, an epidemiologist at the CDC in Atlanta.

"Because young children have less developed immune systems and are more likely to engage in hand-to-mouth behaviors, turtles of any size are not appropriate pets for households, schools or daycares with children younger than 5 years of age."

Sales of turtles with shells less than 4 inches long have been banned in the U.S. since the 1970s, since the creatures are known to carry salmonella bacteria.

A research team led by scientists from the Centers for Disease Control and Prevention (CDC) reported in the journal Pediatrics that, despite the ban, salmonellosis outbreaks tied to turtles have increased since 2006.

The first outbreak of salmonellosis linked to small turtles occurred in 2006 and included four cases. From 2006 to 2011, four outbreaks with a total of 394 cases were reported.

The researchers noted that there's no way to distinguish a healthy turtle from an infected one.

For the study, researchers studied eight additional salmonellosis outbreaks associated with tiny turtles between 2011 and 2014 that included 473 cases in 41 states, Puerto Rico and the District of Columbia.

Researchers studied data about turtle exposure for 102 cases and found that 80 percent of the time, people had turtles at home.

Dr. Elizabeth Barnett, a pediatrics researcher at Boston University School of Medicine who wasn't involved in the study said by email,

"Families should avoid having direct contact with the animals, should not let the turtle roam freely, should avoid placing animals in sinks, bathtubs or other areas where family members may have contact with them, and should dispose of droppings carefully."

 "If these animals are in schools or child care centers, families may want to call this information to the attention of school authorities as they may be unaware of the risk," Barnett said.

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