Salmonella isolates were obtained through the World Health Organization
Global Foodborne Infections Network Surveillance System.
A total of 730 samples of aquaculture products including fish, bullfrog,
spiral shell, clam, Solen strictus (Gould's razor shell), shrimp and other
shellfish were randomly collected in supermarkets and retailers in
Shanghai, China, from2006 to 2011. Samples were placed in sterile plastic
sample bags and chilled on ice during transport to the laboratory at
Shanghai Center for Disease Control. All samples were analyzed on the
day of arrival.