Applied and Environmental Science

Cholera Found in Soft-Shell Turtles

Vibrio cholera, the bacterium that causes cholera, colonizes many of the outer surfaces of soft-shell turtles, including their shells, legs, necks, and the calipash – a gelatinous material just underneath the shell.  Calipash is considered a delicacy in China and East Asia, and turtle meat is often used in soups and stews, making this information vital for public health in those areas.

The discovery was made by researchers at the Chinese Center for Disease Control and Prevention led by Meiying Yan.  Although China has relatively few cholera cases compared to other countries, several small outbreaks of cholera are linked to soft-shell turtles every year, often at rural banquets where meat isn’t cooked thoroughly, was improperly stored at room temperature too long, or kitchen utensils used to handle raw turtle meat were used for other food without being cleaned.  Turtle consumption in rural China has grown to between 220 and 330 million pounds per year.

The researchers discovered how cholera colonizes soft-shell turtles by inserting bioluminescent genes into cholera bacteria, soaking the turtles in a solution of the glowing pathogens, and watching for signs of colonization, which appeared within a few days.  They also injected bioluminescent cholera solution into the turtles’ stomachs and found that the bacteria can colonize turtle intestines.

For more information, go to Applied and Environmental Microbiology, July 2017; 83:14, 14 e00713-17; DOI:10.1128/AEM.00713-17. Original article can be found here.