Small turtles are still causing salmonella infections, mostly in children, researchers report. This despite that fact that they've been banned as pets in the United States since 1975.
The turtles, less than 4 inches long, remain popular pets, the US Centers for Disease Control and Prevention said.
Read: Girl dies of salmonella transmitted by a pet turtle
In a new report released on Wednesday, CDC researchers identified eight salmonella outbreaks between 2011 and 2013, causing 473 illnesses across the country.
"Salmonella from small turtles is a significant public health issue," said study lead researcher Maroya Walters, an epidemiologist with the CDC.
"These outbreaks were in 41 states, Washington, DC, and Puerto Rico, so this is a big, widespread issue," she said.
Walters said that although the small turtles have been banned as pets, they are still available for education, display or research purposes. And they're also sold illegally as pets in many states, she said.
"All of this availability hasn't been halted, so there is still distribution of these turtles," she said.
Dr. Otto Ramos, director of the division of pediatric infectious diseases at Nicklaus Children's Hospital in Miami, said, "This is something that we see on a daily basis."
Many kids suffering from salmonella are admitted to the hospital where they are treated with antibiotics. "It's a major problem," he said.
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Prior to the ban, however, salmonella illnesses linked to turtles sickened about 280,000 people each year, the researchers noted.
The new report was published December 23 online in the journal Pediatrics.
The median age of those sickened by the tiny turtles was 4. More than one-quarter of the children needed to be hospitalized. In the week before getting sick, 68 percent of the patients reported having contact with a turtle. Among these, 88 percent said the turtle was a small one, the CDC report said.
Forty-five percent of the patients were Hispanic, Walters said. However, the study wasn't able to examine the reasons why the Hispanic population was so disproportionately affected, the study authors said.
Few people knew that turtles carry salmonella, Walters said. "Only about 15 percent of patients or their caregivers knew about the link. That contrasts with what we had seen in outbreaks in 2008, when 27 percent of caregivers knew about the link between salmonella and turtles," she said. The researchers added that levels of knowledge about turtles carrying salmonella didn't vary by ethnicity.
The study found that many patients didn't have direct contact with a turtle, but with surfaces the turtle had touched, such as its tank or countertops or sinks where the tank was cleaned.
"You don't actually have to hold the turtle or touch its aquarium or water to get sick, but cross-contamination of surfaces can cause illness as well," Walters said.
Read: Salmonella build-up hard to eliminate
Walters added that the number of people who reported getting sick was likely a minority of those who actually got sick. She estimates that for every reported case, 16 weren't reported. That would mean more than 7,500 people got Salmonella from turtles during the recent outbreaks, according to Walters' estimation.
The researchers traced the contaminated creatures in one outbreak to two Louisiana turtle farms. One outbreak strain was found in turtle pond water from one turtle farm, the CDC said.
All turtles can carry salmonella and transmit it to people, Walters said. "Turtles and other reptiles shouldn't be kept at home or school or any other facilities where there are children under 5," she said.
In homes with older children or where people choose to keep reptiles, it is important to wash your hands after handling turtles or their environment or any area where they roam, Walters said.
According to the CDC, most people infected with salmonella develop diarrhea, fever and abdominal cramps between 12 and 72 hours after infection. The illness usually lasts four to seven days, and most people recover without treatment, the CDC says.
In some cases, diarrhea may be so severe that the patient needs to be hospitalised. In these patients, the salmonella infection may spread from the intestines to the bloodstream and then to other parts of the body. In such cases, salmonella can be fatal unless the person is treated promptly with antibiotics.
The elderly, infants and those with impaired immune systems are more likely to have a severe illness, according to the CDC.
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